mirror of
https://github.com/facebook/rocksdb.git
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71e6a34271
Summary: Add a property to calculate number of background errors encountered to help users build their monitoring Test Plan: Add a unit test. make all check Reviewers: haobo, igor, dhruba Reviewed By: igor CC: ljin, nkg-, yhchiang, leveldb Differential Revision: https://reviews.facebook.net/D16959
4052 lines
138 KiB
C++
4052 lines
138 KiB
C++
// Copyright (c) 2013, Facebook, Inc. All rights reserved.
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// This source code is licensed under the BSD-style license found in the
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// LICENSE file in the root directory of this source tree. An additional grant
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// of patent rights can be found in the PATENTS file in the same directory.
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//
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// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style license that can be
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// found in the LICENSE file. See the AUTHORS file for names of contributors.
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#include "db/db_impl.h"
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#define __STDC_FORMAT_MACROS
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#include <inttypes.h>
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#include <algorithm>
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#include <climits>
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#include <cstdio>
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#include <set>
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#include <stdexcept>
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#include <stdint.h>
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#include <string>
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#include <unordered_set>
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#include <utility>
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#include <vector>
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#include "db/builder.h"
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#include "db/db_iter.h"
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#include "db/dbformat.h"
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#include "db/filename.h"
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#include "db/log_reader.h"
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#include "db/log_writer.h"
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#include "db/memtable.h"
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#include "db/memtable_list.h"
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#include "db/merge_context.h"
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#include "db/merge_helper.h"
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#include "db/prefix_filter_iterator.h"
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#include "db/table_cache.h"
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#include "db/table_properties_collector.h"
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#include "db/tailing_iter.h"
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#include "db/transaction_log_impl.h"
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#include "db/version_set.h"
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#include "db/write_batch_internal.h"
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#include "port/port.h"
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#include "port/likely.h"
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#include "rocksdb/compaction_filter.h"
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#include "rocksdb/db.h"
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#include "rocksdb/env.h"
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#include "rocksdb/merge_operator.h"
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#include "rocksdb/statistics.h"
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#include "rocksdb/status.h"
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#include "rocksdb/table.h"
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#include "table/block.h"
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#include "table/block_based_table_factory.h"
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#include "table/merger.h"
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#include "table/table_builder.h"
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#include "table/two_level_iterator.h"
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#include "util/auto_roll_logger.h"
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#include "util/autovector.h"
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#include "util/build_version.h"
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#include "util/coding.h"
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#include "util/hash_skiplist_rep.h"
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#include "util/hash_linklist_rep.h"
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#include "util/logging.h"
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#include "util/log_buffer.h"
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#include "util/mutexlock.h"
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#include "util/perf_context_imp.h"
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#include "util/stop_watch.h"
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namespace rocksdb {
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int DBImpl::SuperVersion::dummy = 0;
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void* const DBImpl::SuperVersion::kSVInUse = &DBImpl::SuperVersion::dummy;
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void* const DBImpl::SuperVersion::kSVObsolete = nullptr;
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void DumpLeveldbBuildVersion(Logger * log);
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// Information kept for every waiting writer
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struct DBImpl::Writer {
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Status status;
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WriteBatch* batch;
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bool sync;
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bool disableWAL;
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bool done;
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port::CondVar cv;
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explicit Writer(port::Mutex* mu) : cv(mu) { }
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};
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struct DBImpl::CompactionState {
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Compaction* const compaction;
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// If there were two snapshots with seq numbers s1 and
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// s2 and s1 < s2, and if we find two instances of a key k1 then lies
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// entirely within s1 and s2, then the earlier version of k1 can be safely
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// deleted because that version is not visible in any snapshot.
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std::vector<SequenceNumber> existing_snapshots;
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// Files produced by compaction
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struct Output {
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uint64_t number;
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uint64_t file_size;
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InternalKey smallest, largest;
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SequenceNumber smallest_seqno, largest_seqno;
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};
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std::vector<Output> outputs;
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std::list<uint64_t> allocated_file_numbers;
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// State kept for output being generated
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unique_ptr<WritableFile> outfile;
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unique_ptr<TableBuilder> builder;
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uint64_t total_bytes;
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Output* current_output() { return &outputs[outputs.size()-1]; }
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explicit CompactionState(Compaction* c)
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: compaction(c),
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total_bytes(0) {
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}
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// Create a client visible context of this compaction
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CompactionFilter::Context GetFilterContext() {
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CompactionFilter::Context context;
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context.is_full_compaction = compaction->IsFullCompaction();
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context.is_manual_compaction = compaction->IsManualCompaction();
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return context;
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}
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};
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// Fix user-supplied options to be reasonable
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template <class T, class V>
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static void ClipToRange(T* ptr, V minvalue, V maxvalue) {
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if (static_cast<V>(*ptr) > maxvalue) *ptr = maxvalue;
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if (static_cast<V>(*ptr) < minvalue) *ptr = minvalue;
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}
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Options SanitizeOptions(const std::string& dbname,
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const InternalKeyComparator* icmp,
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const InternalFilterPolicy* ipolicy,
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const Options& src) {
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Options result = src;
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result.filter_policy = (src.filter_policy != nullptr) ? ipolicy : nullptr;
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// result.max_open_files means an "infinite" open files.
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if (result.max_open_files != -1) {
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ClipToRange(&result.max_open_files, 20, 1000000);
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}
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ClipToRange(&result.write_buffer_size, ((size_t)64)<<10,
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((size_t)64)<<30);
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ClipToRange(&result.block_size, 1<<10, 4<<20);
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// if user sets arena_block_size, we trust user to use this value. Otherwise,
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// calculate a proper value from writer_buffer_size;
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if (result.arena_block_size <= 0) {
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result.arena_block_size = result.write_buffer_size / 10;
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}
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result.min_write_buffer_number_to_merge = std::min(
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result.min_write_buffer_number_to_merge, result.max_write_buffer_number-1);
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if (result.info_log == nullptr) {
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Status s = CreateLoggerFromOptions(dbname, result.db_log_dir, src.env,
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result, &result.info_log);
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if (!s.ok()) {
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// No place suitable for logging
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result.info_log = nullptr;
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}
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}
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if (result.block_cache == nullptr && !result.no_block_cache) {
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result.block_cache = NewLRUCache(8 << 20);
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}
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result.compression_per_level = src.compression_per_level;
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if (result.block_size_deviation < 0 || result.block_size_deviation > 100) {
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result.block_size_deviation = 0;
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}
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if (result.max_mem_compaction_level >= result.num_levels) {
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result.max_mem_compaction_level = result.num_levels - 1;
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}
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if (result.soft_rate_limit > result.hard_rate_limit) {
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result.soft_rate_limit = result.hard_rate_limit;
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}
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if (result.compaction_filter) {
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Log(result.info_log, "Compaction filter specified, ignore factory");
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}
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if (result.prefix_extractor) {
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Log(result.info_log, "prefix extractor %s in use.",
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result.prefix_extractor->Name());
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} else {
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assert(result.memtable_factory);
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Slice name = result.memtable_factory->Name();
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if (name.compare("HashSkipListRepFactory") == 0 ||
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name.compare("HashLinkListRepFactory") == 0) {
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Log(result.info_log, "prefix extractor is not provided while using %s. "
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"fallback to skiplist", name.ToString().c_str());
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result.memtable_factory = std::make_shared<SkipListFactory>();
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}
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}
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if (result.wal_dir.empty()) {
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// Use dbname as default
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result.wal_dir = dbname;
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}
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// -- Sanitize the table properties collector
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// All user defined properties collectors will be wrapped by
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// UserKeyTablePropertiesCollector since for them they only have the
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// knowledge of the user keys; internal keys are invisible to them.
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auto& collectors = result.table_properties_collectors;
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for (size_t i = 0; i < result.table_properties_collectors.size(); ++i) {
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assert(collectors[i]);
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collectors[i] =
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std::make_shared<UserKeyTablePropertiesCollector>(collectors[i]);
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}
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// Add collector to collect internal key statistics
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collectors.push_back(
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std::make_shared<InternalKeyPropertiesCollector>()
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);
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return result;
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}
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CompressionType GetCompressionType(const Options& options, int level,
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const bool enable_compression) {
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if (!enable_compression) {
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// disable compression
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return kNoCompression;
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}
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// If the use has specified a different compression level for each level,
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// then pick the compresison for that level.
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if (!options.compression_per_level.empty()) {
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const int n = options.compression_per_level.size() - 1;
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// It is possible for level_ to be -1; in that case, we use level
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// 0's compression. This occurs mostly in backwards compatibility
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// situations when the builder doesn't know what level the file
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// belongs to. Likewise, if level_ is beyond the end of the
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// specified compression levels, use the last value.
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return options.compression_per_level[std::max(0, std::min(level, n))];
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} else {
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return options.compression;
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}
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}
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CompressionType GetCompressionFlush(const Options& options) {
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// Compressing memtable flushes might not help unless the sequential load
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// optimization is used for leveled compaction. Otherwise the CPU and
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// latency overhead is not offset by saving much space.
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bool can_compress;
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if (options.compaction_style == kCompactionStyleUniversal) {
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can_compress =
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(options.compaction_options_universal.compression_size_percent < 0);
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} else {
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// For leveled compress when min_level_to_compress == 0.
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can_compress = (GetCompressionType(options, 0, true) != kNoCompression);
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}
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if (can_compress) {
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return options.compression;
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} else {
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return kNoCompression;
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}
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}
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DBImpl::DBImpl(const Options& options, const std::string& dbname)
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: env_(options.env),
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dbname_(dbname),
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internal_comparator_(options.comparator),
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options_(SanitizeOptions(dbname, &internal_comparator_,
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&internal_filter_policy_, options)),
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internal_filter_policy_(options.filter_policy),
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owns_info_log_(options_.info_log != options.info_log),
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db_lock_(nullptr),
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mutex_(options.use_adaptive_mutex),
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shutting_down_(nullptr),
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bg_cv_(&mutex_),
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mem_(new MemTable(internal_comparator_, options_)),
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imm_(options_.min_write_buffer_number_to_merge),
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logfile_number_(0),
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super_version_(nullptr),
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super_version_number_(0),
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local_sv_(new ThreadLocalPtr(&SuperVersionUnrefHandle)),
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tmp_batch_(),
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bg_schedule_needed_(false),
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bg_compaction_scheduled_(0),
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bg_manual_only_(0),
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bg_flush_scheduled_(0),
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bg_logstats_scheduled_(false),
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manual_compaction_(nullptr),
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logger_(nullptr),
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disable_delete_obsolete_files_(0),
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delete_obsolete_files_last_run_(options.env->NowMicros()),
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purge_wal_files_last_run_(0),
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last_stats_dump_time_microsec_(0),
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default_interval_to_delete_obsolete_WAL_(600),
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flush_on_destroy_(false),
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internal_stats_(options.num_levels, options.env,
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options.statistics.get()),
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delayed_writes_(0),
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storage_options_(options),
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bg_work_gate_closed_(false),
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refitting_level_(false),
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opened_successfully_(false) {
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mem_->Ref();
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env_->GetAbsolutePath(dbname, &db_absolute_path_);
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// Reserve ten files or so for other uses and give the rest to TableCache.
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// Give a large number for setting of "infinite" open files.
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const int table_cache_size =
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(options_.max_open_files == -1) ?
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4194304 : options_.max_open_files - 10;
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table_cache_.reset(new TableCache(dbname_, &options_,
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storage_options_, table_cache_size));
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versions_.reset(new VersionSet(dbname_, &options_, storage_options_,
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table_cache_.get(), &internal_comparator_));
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DumpLeveldbBuildVersion(options_.info_log.get());
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options_.Dump(options_.info_log.get());
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char name[100];
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Status s = env_->GetHostName(name, 100L);
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if (s.ok()) {
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host_name_ = name;
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} else {
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Log(options_.info_log, "Can't get hostname, use localhost as host name.");
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host_name_ = "localhost";
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}
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last_log_ts = 0;
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LogFlush(options_.info_log);
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}
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DBImpl::~DBImpl() {
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// Wait for background work to finish
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if (flush_on_destroy_ && mem_->GetFirstSequenceNumber() != 0) {
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FlushMemTable(FlushOptions());
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}
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mutex_.Lock();
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shutting_down_.Release_Store(this); // Any non-nullptr value is ok
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while (bg_compaction_scheduled_ ||
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bg_flush_scheduled_ ||
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bg_logstats_scheduled_) {
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bg_cv_.Wait();
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}
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mutex_.Unlock();
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// Release SuperVersion reference kept in ThreadLocalPtr.
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// This must be done outside of mutex_ since unref handler can lock mutex.
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// It also needs to be done after FlushMemTable, which can trigger local_sv_
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// access.
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delete local_sv_;
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mutex_.Lock();
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if (options_.allow_thread_local) {
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// Clean up obsolete files due to SuperVersion release.
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// (1) Need to delete to obsolete files before closing because RepairDB()
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// scans all existing files in the file system and builds manifest file.
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// Keeping obsolete files confuses the repair process.
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// (2) Need to check if we Open()/Recover() the DB successfully before
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// deleting because if VersionSet recover fails (may be due to corrupted
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// manifest file), it is not able to identify live files correctly. As a
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// result, all "live" files can get deleted by accident. However, corrupted
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// manifest is recoverable by RepairDB().
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if (opened_successfully_) {
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DeletionState deletion_state;
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FindObsoleteFiles(deletion_state, true);
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// manifest number starting from 2
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deletion_state.manifest_file_number = 1;
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if (deletion_state.HaveSomethingToDelete()) {
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PurgeObsoleteFiles(deletion_state);
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}
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}
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}
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if (super_version_ != nullptr) {
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bool is_last_reference __attribute__((unused));
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is_last_reference = super_version_->Unref();
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assert(is_last_reference);
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super_version_->Cleanup();
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delete super_version_;
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}
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mutex_.Unlock();
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if (db_lock_ != nullptr) {
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env_->UnlockFile(db_lock_);
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}
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if (mem_ != nullptr) {
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delete mem_->Unref();
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}
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autovector<MemTable*> to_delete;
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imm_.current()->Unref(&to_delete);
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for (MemTable* m: to_delete) {
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delete m;
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}
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// versions need to be destroyed before table_cache since it can holds
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// references to table_cache.
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versions_.reset();
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LogFlush(options_.info_log);
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}
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// Do not flush and close database elegantly. Simulate a crash.
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void DBImpl::TEST_Destroy_DBImpl() {
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// ensure that no new memtable flushes can occur
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flush_on_destroy_ = false;
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// wait till all background compactions are done.
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mutex_.Lock();
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while (bg_compaction_scheduled_ ||
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bg_flush_scheduled_ ||
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bg_logstats_scheduled_) {
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bg_cv_.Wait();
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}
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mutex_.Unlock();
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// Release SuperVersion reference kept in ThreadLocalPtr.
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// This must be done outside of mutex_ since unref handler can lock mutex.
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// It also needs to be done after FlushMemTable, which can trigger local_sv_
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// access.
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delete local_sv_;
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mutex_.Lock();
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if (super_version_ != nullptr) {
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bool is_last_reference __attribute__((unused));
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is_last_reference = super_version_->Unref();
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assert(is_last_reference);
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super_version_->Cleanup();
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delete super_version_;
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}
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// Prevent new compactions from occuring.
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bg_work_gate_closed_ = true;
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const int LargeNumber = 10000000;
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bg_compaction_scheduled_ += LargeNumber;
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mutex_.Unlock();
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LogFlush(options_.info_log);
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// force release the lock file.
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if (db_lock_ != nullptr) {
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env_->UnlockFile(db_lock_);
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}
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log_.reset();
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versions_.reset();
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table_cache_.reset();
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}
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uint64_t DBImpl::TEST_Current_Manifest_FileNo() {
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return versions_->ManifestFileNumber();
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}
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Status DBImpl::NewDB() {
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VersionEdit new_db;
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new_db.SetVersionNumber();
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new_db.SetComparatorName(user_comparator()->Name());
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new_db.SetLogNumber(0);
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new_db.SetNextFile(2);
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new_db.SetLastSequence(0);
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const std::string manifest = DescriptorFileName(dbname_, 1);
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unique_ptr<WritableFile> file;
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Status s = env_->NewWritableFile(
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manifest, &file, env_->OptimizeForManifestWrite(storage_options_));
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if (!s.ok()) {
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return s;
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}
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file->SetPreallocationBlockSize(options_.manifest_preallocation_size);
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{
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log::Writer log(std::move(file));
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std::string record;
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new_db.EncodeTo(&record);
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s = log.AddRecord(record);
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}
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if (s.ok()) {
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// Make "CURRENT" file that points to the new manifest file.
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s = SetCurrentFile(env_, dbname_, 1);
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} else {
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env_->DeleteFile(manifest);
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}
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return s;
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}
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void DBImpl::MaybeIgnoreError(Status* s) const {
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if (s->ok() || options_.paranoid_checks) {
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// No change needed
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} else {
|
|
Log(options_.info_log, "Ignoring error %s", s->ToString().c_str());
|
|
*s = Status::OK();
|
|
}
|
|
}
|
|
|
|
const Status DBImpl::CreateArchivalDirectory() {
|
|
if (options_.WAL_ttl_seconds > 0 || options_.WAL_size_limit_MB > 0) {
|
|
std::string archivalPath = ArchivalDirectory(options_.wal_dir);
|
|
return env_->CreateDirIfMissing(archivalPath);
|
|
}
|
|
return Status::OK();
|
|
}
|
|
|
|
void DBImpl::PrintStatistics() {
|
|
auto dbstats = options_.statistics.get();
|
|
if (dbstats) {
|
|
Log(options_.info_log,
|
|
"STATISTCS:\n %s",
|
|
dbstats->ToString().c_str());
|
|
}
|
|
}
|
|
|
|
void DBImpl::MaybeDumpStats() {
|
|
if (options_.stats_dump_period_sec == 0) return;
|
|
|
|
const uint64_t now_micros = env_->NowMicros();
|
|
|
|
if (last_stats_dump_time_microsec_ +
|
|
options_.stats_dump_period_sec * 1000000
|
|
<= now_micros) {
|
|
// Multiple threads could race in here simultaneously.
|
|
// However, the last one will update last_stats_dump_time_microsec_
|
|
// atomically. We could see more than one dump during one dump
|
|
// period in rare cases.
|
|
last_stats_dump_time_microsec_ = now_micros;
|
|
std::string stats;
|
|
GetProperty("rocksdb.stats", &stats);
|
|
Log(options_.info_log, "%s", stats.c_str());
|
|
PrintStatistics();
|
|
}
|
|
}
|
|
|
|
// DBImpl::SuperVersion methods
|
|
DBImpl::SuperVersion::~SuperVersion() {
|
|
for (auto td : to_delete) {
|
|
delete td;
|
|
}
|
|
}
|
|
|
|
DBImpl::SuperVersion* DBImpl::SuperVersion::Ref() {
|
|
refs.fetch_add(1, std::memory_order_relaxed);
|
|
return this;
|
|
}
|
|
|
|
bool DBImpl::SuperVersion::Unref() {
|
|
assert(refs > 0);
|
|
// fetch_sub returns the previous value of yoeref
|
|
return refs.fetch_sub(1, std::memory_order_relaxed) == 1;
|
|
}
|
|
|
|
void DBImpl::SuperVersion::Cleanup() {
|
|
db->mutex_.AssertHeld();
|
|
assert(refs.load(std::memory_order_relaxed) == 0);
|
|
imm->Unref(&to_delete);
|
|
MemTable* m = mem->Unref();
|
|
if (m != nullptr) {
|
|
to_delete.push_back(m);
|
|
}
|
|
current->Unref();
|
|
}
|
|
|
|
void DBImpl::SuperVersion::Init(MemTable* new_mem, MemTableListVersion* new_imm,
|
|
Version* new_current) {
|
|
db->mutex_.AssertHeld();
|
|
mem = new_mem;
|
|
imm = new_imm;
|
|
current = new_current;
|
|
mem->Ref();
|
|
imm->Ref();
|
|
current->Ref();
|
|
refs.store(1, std::memory_order_relaxed);
|
|
}
|
|
|
|
// Returns the list of live files in 'sst_live' and the list
|
|
// of all files in the filesystem in 'candidate_files'.
|
|
// no_full_scan = true -- never do the full scan using GetChildren()
|
|
// force = false -- don't force the full scan, except every
|
|
// options_.delete_obsolete_files_period_micros
|
|
// force = true -- force the full scan
|
|
void DBImpl::FindObsoleteFiles(DeletionState& deletion_state,
|
|
bool force,
|
|
bool no_full_scan) {
|
|
mutex_.AssertHeld();
|
|
|
|
// if deletion is disabled, do nothing
|
|
if (disable_delete_obsolete_files_ > 0) {
|
|
return;
|
|
}
|
|
|
|
bool doing_the_full_scan = false;
|
|
|
|
// logic for figurint out if we're doing the full scan
|
|
if (no_full_scan) {
|
|
doing_the_full_scan = false;
|
|
} else if (force || options_.delete_obsolete_files_period_micros == 0) {
|
|
doing_the_full_scan = true;
|
|
} else {
|
|
const uint64_t now_micros = env_->NowMicros();
|
|
if (delete_obsolete_files_last_run_ +
|
|
options_.delete_obsolete_files_period_micros < now_micros) {
|
|
doing_the_full_scan = true;
|
|
delete_obsolete_files_last_run_ = now_micros;
|
|
}
|
|
}
|
|
|
|
// get obsolete files
|
|
versions_->GetObsoleteFiles(&deletion_state.sst_delete_files);
|
|
|
|
// store the current filenum, lognum, etc
|
|
deletion_state.manifest_file_number = versions_->ManifestFileNumber();
|
|
deletion_state.pending_manifest_file_number =
|
|
versions_->PendingManifestFileNumber();
|
|
deletion_state.log_number = versions_->LogNumber();
|
|
deletion_state.prev_log_number = versions_->PrevLogNumber();
|
|
|
|
if (!doing_the_full_scan && !deletion_state.HaveSomethingToDelete()) {
|
|
// avoid filling up sst_live if we're sure that we
|
|
// are not going to do the full scan and that we don't have
|
|
// anything to delete at the moment
|
|
return;
|
|
}
|
|
|
|
// don't delete live files
|
|
deletion_state.sst_live.assign(pending_outputs_.begin(),
|
|
pending_outputs_.end());
|
|
versions_->AddLiveFiles(&deletion_state.sst_live);
|
|
|
|
if (doing_the_full_scan) {
|
|
// set of all files in the directory. We'll exclude files that are still
|
|
// alive in the subsequent processings.
|
|
env_->GetChildren(
|
|
dbname_, &deletion_state.candidate_files
|
|
); // Ignore errors
|
|
|
|
//Add log files in wal_dir
|
|
if (options_.wal_dir != dbname_) {
|
|
std::vector<std::string> log_files;
|
|
env_->GetChildren(options_.wal_dir, &log_files); // Ignore errors
|
|
deletion_state.candidate_files.insert(
|
|
deletion_state.candidate_files.end(),
|
|
log_files.begin(),
|
|
log_files.end()
|
|
);
|
|
}
|
|
}
|
|
}
|
|
|
|
// Diffs the files listed in filenames and those that do not
|
|
// belong to live files are posibly removed. Also, removes all the
|
|
// files in sst_delete_files and log_delete_files.
|
|
// It is not necessary to hold the mutex when invoking this method.
|
|
void DBImpl::PurgeObsoleteFiles(DeletionState& state) {
|
|
// we'd better have sth to delete
|
|
assert(state.HaveSomethingToDelete());
|
|
|
|
// this checks if FindObsoleteFiles() was run before. If not, don't do
|
|
// PurgeObsoleteFiles(). If FindObsoleteFiles() was run, we need to also
|
|
// run PurgeObsoleteFiles(), even if disable_delete_obsolete_files_ is true
|
|
if (state.manifest_file_number == 0) {
|
|
return;
|
|
}
|
|
|
|
// Now, convert live list to an unordered set, WITHOUT mutex held;
|
|
// set is slow.
|
|
std::unordered_set<uint64_t> sst_live(state.sst_live.begin(),
|
|
state.sst_live.end());
|
|
|
|
auto& candidate_files = state.candidate_files;
|
|
candidate_files.reserve(
|
|
candidate_files.size() +
|
|
state.sst_delete_files.size() +
|
|
state.log_delete_files.size());
|
|
// We may ignore the dbname when generating the file names.
|
|
const char* kDumbDbName = "";
|
|
for (auto file : state.sst_delete_files) {
|
|
candidate_files.push_back(
|
|
TableFileName(kDumbDbName, file->number).substr(1)
|
|
);
|
|
delete file;
|
|
}
|
|
|
|
for (auto file_num : state.log_delete_files) {
|
|
if (file_num > 0) {
|
|
candidate_files.push_back(LogFileName(kDumbDbName, file_num).substr(1));
|
|
}
|
|
}
|
|
|
|
// dedup state.candidate_files so we don't try to delete the same
|
|
// file twice
|
|
sort(candidate_files.begin(), candidate_files.end());
|
|
candidate_files.erase(unique(candidate_files.begin(), candidate_files.end()),
|
|
candidate_files.end());
|
|
|
|
std::vector<std::string> old_info_log_files;
|
|
|
|
for (const auto& to_delete : candidate_files) {
|
|
uint64_t number;
|
|
FileType type;
|
|
// Ignore file if we cannot recognize it.
|
|
if (!ParseFileName(to_delete, &number, &type)) {
|
|
continue;
|
|
}
|
|
|
|
bool keep = true;
|
|
switch (type) {
|
|
case kLogFile:
|
|
keep = ((number >= state.log_number) ||
|
|
(number == state.prev_log_number));
|
|
break;
|
|
case kDescriptorFile:
|
|
// Keep my manifest file, and any newer incarnations'
|
|
// (can happen during manifest roll)
|
|
keep = (number >= state.manifest_file_number);
|
|
break;
|
|
case kTableFile:
|
|
keep = (sst_live.find(number) != sst_live.end());
|
|
break;
|
|
case kTempFile:
|
|
// Any temp files that are currently being written to must
|
|
// be recorded in pending_outputs_, which is inserted into "live".
|
|
// Also, SetCurrentFile creates a temp file when writing out new
|
|
// manifest, which is equal to state.pending_manifest_file_number. We
|
|
// should not delete that file
|
|
keep = (sst_live.find(number) != sst_live.end()) ||
|
|
(number == state.pending_manifest_file_number);
|
|
break;
|
|
case kInfoLogFile:
|
|
keep = true;
|
|
if (number != 0) {
|
|
old_info_log_files.push_back(to_delete);
|
|
}
|
|
break;
|
|
case kCurrentFile:
|
|
case kDBLockFile:
|
|
case kIdentityFile:
|
|
case kMetaDatabase:
|
|
keep = true;
|
|
break;
|
|
}
|
|
|
|
if (keep) {
|
|
continue;
|
|
}
|
|
|
|
if (type == kTableFile) {
|
|
// evict from cache
|
|
table_cache_->Evict(number);
|
|
}
|
|
|
|
std::string fname = ((type == kLogFile) ? options_.wal_dir : dbname_) +
|
|
"/" + to_delete;
|
|
if (type == kLogFile &&
|
|
(options_.WAL_ttl_seconds > 0 || options_.WAL_size_limit_MB > 0)) {
|
|
auto archived_log_name = ArchivedLogFileName(options_.wal_dir, number);
|
|
Status s = env_->RenameFile(fname, archived_log_name);
|
|
Log(options_.info_log,
|
|
"Move log file %s to %s -- %s\n",
|
|
fname.c_str(), archived_log_name.c_str(), s.ToString().c_str());
|
|
} else {
|
|
Status s = env_->DeleteFile(fname);
|
|
Log(options_.info_log, "Delete %s type=%d #%lu -- %s\n",
|
|
fname.c_str(), type, (unsigned long)number,
|
|
s.ToString().c_str());
|
|
}
|
|
}
|
|
|
|
// Delete old info log files.
|
|
size_t old_info_log_file_count = old_info_log_files.size();
|
|
// NOTE: Currently we only support log purge when options_.db_log_dir is
|
|
// located in `dbname` directory.
|
|
if (old_info_log_file_count >= options_.keep_log_file_num &&
|
|
options_.db_log_dir.empty()) {
|
|
std::sort(old_info_log_files.begin(), old_info_log_files.end());
|
|
size_t end = old_info_log_file_count - options_.keep_log_file_num;
|
|
for (unsigned int i = 0; i <= end; i++) {
|
|
std::string& to_delete = old_info_log_files.at(i);
|
|
Log(options_.info_log, "Delete info log file %s\n", to_delete.c_str());
|
|
Status s = env_->DeleteFile(dbname_ + "/" + to_delete);
|
|
if (!s.ok()) {
|
|
Log(options_.info_log, "Delete info log file %s FAILED -- %s\n",
|
|
to_delete.c_str(), s.ToString().c_str());
|
|
}
|
|
}
|
|
}
|
|
PurgeObsoleteWALFiles();
|
|
LogFlush(options_.info_log);
|
|
}
|
|
|
|
void DBImpl::DeleteObsoleteFiles() {
|
|
mutex_.AssertHeld();
|
|
DeletionState deletion_state;
|
|
FindObsoleteFiles(deletion_state, true);
|
|
if (deletion_state.HaveSomethingToDelete()) {
|
|
PurgeObsoleteFiles(deletion_state);
|
|
}
|
|
}
|
|
|
|
// 1. Go through all archived files and
|
|
// a. if ttl is enabled, delete outdated files
|
|
// b. if archive size limit is enabled, delete empty files,
|
|
// compute file number and size.
|
|
// 2. If size limit is enabled:
|
|
// a. compute how many files should be deleted
|
|
// b. get sorted non-empty archived logs
|
|
// c. delete what should be deleted
|
|
void DBImpl::PurgeObsoleteWALFiles() {
|
|
bool const ttl_enabled = options_.WAL_ttl_seconds > 0;
|
|
bool const size_limit_enabled = options_.WAL_size_limit_MB > 0;
|
|
if (!ttl_enabled && !size_limit_enabled) {
|
|
return;
|
|
}
|
|
|
|
int64_t current_time;
|
|
Status s = env_->GetCurrentTime(¤t_time);
|
|
if (!s.ok()) {
|
|
Log(options_.info_log, "Can't get current time: %s", s.ToString().c_str());
|
|
assert(false);
|
|
return;
|
|
}
|
|
uint64_t const now_seconds = static_cast<uint64_t>(current_time);
|
|
uint64_t const time_to_check = (ttl_enabled && !size_limit_enabled) ?
|
|
options_.WAL_ttl_seconds / 2 : default_interval_to_delete_obsolete_WAL_;
|
|
|
|
if (purge_wal_files_last_run_ + time_to_check > now_seconds) {
|
|
return;
|
|
}
|
|
|
|
purge_wal_files_last_run_ = now_seconds;
|
|
|
|
std::string archival_dir = ArchivalDirectory(options_.wal_dir);
|
|
std::vector<std::string> files;
|
|
s = env_->GetChildren(archival_dir, &files);
|
|
if (!s.ok()) {
|
|
Log(options_.info_log, "Can't get archive files: %s", s.ToString().c_str());
|
|
assert(false);
|
|
return;
|
|
}
|
|
|
|
size_t log_files_num = 0;
|
|
uint64_t log_file_size = 0;
|
|
|
|
for (auto& f : files) {
|
|
uint64_t number;
|
|
FileType type;
|
|
if (ParseFileName(f, &number, &type) && type == kLogFile) {
|
|
std::string const file_path = archival_dir + "/" + f;
|
|
if (ttl_enabled) {
|
|
uint64_t file_m_time;
|
|
Status const s = env_->GetFileModificationTime(file_path,
|
|
&file_m_time);
|
|
if (!s.ok()) {
|
|
Log(options_.info_log, "Can't get file mod time: %s: %s",
|
|
file_path.c_str(), s.ToString().c_str());
|
|
continue;
|
|
}
|
|
if (now_seconds - file_m_time > options_.WAL_ttl_seconds) {
|
|
Status const s = env_->DeleteFile(file_path);
|
|
if (!s.ok()) {
|
|
Log(options_.info_log, "Can't delete file: %s: %s",
|
|
file_path.c_str(), s.ToString().c_str());
|
|
continue;
|
|
}
|
|
continue;
|
|
}
|
|
}
|
|
|
|
if (size_limit_enabled) {
|
|
uint64_t file_size;
|
|
Status const s = env_->GetFileSize(file_path, &file_size);
|
|
if (!s.ok()) {
|
|
Log(options_.info_log, "Can't get file size: %s: %s",
|
|
file_path.c_str(), s.ToString().c_str());
|
|
return;
|
|
} else {
|
|
if (file_size > 0) {
|
|
log_file_size = std::max(log_file_size, file_size);
|
|
++log_files_num;
|
|
} else {
|
|
Status s = env_->DeleteFile(file_path);
|
|
if (!s.ok()) {
|
|
Log(options_.info_log, "Can't delete file: %s: %s",
|
|
file_path.c_str(), s.ToString().c_str());
|
|
continue;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
if (0 == log_files_num || !size_limit_enabled) {
|
|
return;
|
|
}
|
|
|
|
size_t const files_keep_num = options_.WAL_size_limit_MB *
|
|
1024 * 1024 / log_file_size;
|
|
if (log_files_num <= files_keep_num) {
|
|
return;
|
|
}
|
|
|
|
size_t files_del_num = log_files_num - files_keep_num;
|
|
VectorLogPtr archived_logs;
|
|
AppendSortedWalsOfType(archival_dir, archived_logs, kArchivedLogFile);
|
|
|
|
if (files_del_num > archived_logs.size()) {
|
|
Log(options_.info_log, "Trying to delete more archived log files than "
|
|
"exist. Deleting all");
|
|
files_del_num = archived_logs.size();
|
|
}
|
|
|
|
for (size_t i = 0; i < files_del_num; ++i) {
|
|
std::string const file_path = archived_logs[i]->PathName();
|
|
Status const s = DeleteFile(file_path);
|
|
if (!s.ok()) {
|
|
Log(options_.info_log, "Can't delete file: %s: %s",
|
|
file_path.c_str(), s.ToString().c_str());
|
|
continue;
|
|
}
|
|
}
|
|
}
|
|
|
|
Status DBImpl::Recover(bool read_only, bool error_if_log_file_exist) {
|
|
mutex_.AssertHeld();
|
|
|
|
assert(db_lock_ == nullptr);
|
|
if (!read_only) {
|
|
// We call CreateDirIfMissing() as the directory may already exist (if we
|
|
// are reopening a DB), when this happens we don't want creating the
|
|
// directory to cause an error. However, we need to check if creating the
|
|
// directory fails or else we may get an obscure message about the lock
|
|
// file not existing. One real-world example of this occurring is if
|
|
// env->CreateDirIfMissing() doesn't create intermediate directories, e.g.
|
|
// when dbname_ is "dir/db" but when "dir" doesn't exist.
|
|
Status s = env_->CreateDirIfMissing(dbname_);
|
|
if (!s.ok()) {
|
|
return s;
|
|
}
|
|
|
|
s = env_->NewDirectory(dbname_, &db_directory_);
|
|
if (!s.ok()) {
|
|
return s;
|
|
}
|
|
|
|
s = env_->LockFile(LockFileName(dbname_), &db_lock_);
|
|
if (!s.ok()) {
|
|
return s;
|
|
}
|
|
|
|
if (!env_->FileExists(CurrentFileName(dbname_))) {
|
|
if (options_.create_if_missing) {
|
|
// TODO: add merge_operator name check
|
|
s = NewDB();
|
|
if (!s.ok()) {
|
|
return s;
|
|
}
|
|
} else {
|
|
return Status::InvalidArgument(
|
|
dbname_, "does not exist (create_if_missing is false)");
|
|
}
|
|
} else {
|
|
if (options_.error_if_exists) {
|
|
return Status::InvalidArgument(
|
|
dbname_, "exists (error_if_exists is true)");
|
|
}
|
|
}
|
|
// Check for the IDENTITY file and create it if not there
|
|
if (!env_->FileExists(IdentityFileName(dbname_))) {
|
|
s = SetIdentityFile(env_, dbname_);
|
|
if (!s.ok()) {
|
|
return s;
|
|
}
|
|
}
|
|
}
|
|
|
|
Status s = versions_->Recover();
|
|
if (s.ok()) {
|
|
SequenceNumber max_sequence(0);
|
|
|
|
// Recover from all newer log files than the ones named in the
|
|
// descriptor (new log files may have been added by the previous
|
|
// incarnation without registering them in the descriptor).
|
|
//
|
|
// Note that PrevLogNumber() is no longer used, but we pay
|
|
// attention to it in case we are recovering a database
|
|
// produced by an older version of rocksdb.
|
|
const uint64_t min_log = versions_->LogNumber();
|
|
const uint64_t prev_log = versions_->PrevLogNumber();
|
|
std::vector<std::string> filenames;
|
|
s = env_->GetChildren(options_.wal_dir, &filenames);
|
|
if (!s.ok()) {
|
|
return s;
|
|
}
|
|
|
|
std::vector<uint64_t> logs;
|
|
for (size_t i = 0; i < filenames.size(); i++) {
|
|
uint64_t number;
|
|
FileType type;
|
|
if (ParseFileName(filenames[i], &number, &type)
|
|
&& type == kLogFile
|
|
&& ((number >= min_log) || (number == prev_log))) {
|
|
logs.push_back(number);
|
|
}
|
|
}
|
|
|
|
if (logs.size() > 0 && error_if_log_file_exist) {
|
|
return Status::Corruption(""
|
|
"The db was opened in readonly mode with error_if_log_file_exist"
|
|
"flag but a log file already exists");
|
|
}
|
|
|
|
// Recover in the order in which the logs were generated
|
|
std::sort(logs.begin(), logs.end());
|
|
for (const auto& log : logs) {
|
|
// The previous incarnation may not have written any MANIFEST
|
|
// records after allocating this log number. So we manually
|
|
// update the file number allocation counter in VersionSet.
|
|
versions_->MarkFileNumberUsed(log);
|
|
s = RecoverLogFile(log, &max_sequence, read_only);
|
|
}
|
|
|
|
if (s.ok()) {
|
|
if (versions_->LastSequence() < max_sequence) {
|
|
versions_->SetLastSequence(max_sequence);
|
|
}
|
|
SetTickerCount(options_.statistics.get(), SEQUENCE_NUMBER,
|
|
versions_->LastSequence());
|
|
}
|
|
}
|
|
|
|
return s;
|
|
}
|
|
|
|
Status DBImpl::RecoverLogFile(uint64_t log_number, SequenceNumber* max_sequence,
|
|
bool read_only) {
|
|
struct LogReporter : public log::Reader::Reporter {
|
|
Env* env;
|
|
Logger* info_log;
|
|
const char* fname;
|
|
Status* status; // nullptr if options_.paranoid_checks==false or
|
|
// options_.skip_log_error_on_recovery==true
|
|
virtual void Corruption(size_t bytes, const Status& s) {
|
|
Log(info_log, "%s%s: dropping %d bytes; %s",
|
|
(this->status == nullptr ? "(ignoring error) " : ""),
|
|
fname, static_cast<int>(bytes), s.ToString().c_str());
|
|
if (this->status != nullptr && this->status->ok()) *this->status = s;
|
|
}
|
|
};
|
|
|
|
mutex_.AssertHeld();
|
|
|
|
VersionEdit edit;
|
|
|
|
// Open the log file
|
|
std::string fname = LogFileName(options_.wal_dir, log_number);
|
|
unique_ptr<SequentialFile> file;
|
|
Status status = env_->NewSequentialFile(fname, &file, storage_options_);
|
|
if (!status.ok()) {
|
|
MaybeIgnoreError(&status);
|
|
return status;
|
|
}
|
|
|
|
// Create the log reader.
|
|
LogReporter reporter;
|
|
reporter.env = env_;
|
|
reporter.info_log = options_.info_log.get();
|
|
reporter.fname = fname.c_str();
|
|
reporter.status = (options_.paranoid_checks &&
|
|
!options_.skip_log_error_on_recovery ? &status : nullptr);
|
|
// We intentially make log::Reader do checksumming even if
|
|
// paranoid_checks==false so that corruptions cause entire commits
|
|
// to be skipped instead of propagating bad information (like overly
|
|
// large sequence numbers).
|
|
log::Reader reader(std::move(file), &reporter, true/*checksum*/,
|
|
0/*initial_offset*/);
|
|
Log(options_.info_log, "Recovering log #%lu",
|
|
(unsigned long) log_number);
|
|
|
|
// Read all the records and add to a memtable
|
|
std::string scratch;
|
|
Slice record;
|
|
WriteBatch batch;
|
|
bool memtable_empty = true;
|
|
while (reader.ReadRecord(&record, &scratch)) {
|
|
if (record.size() < 12) {
|
|
reporter.Corruption(
|
|
record.size(), Status::Corruption("log record too small"));
|
|
continue;
|
|
}
|
|
WriteBatchInternal::SetContents(&batch, record);
|
|
|
|
status = WriteBatchInternal::InsertInto(&batch, mem_, &options_);
|
|
memtable_empty = false;
|
|
MaybeIgnoreError(&status);
|
|
if (!status.ok()) {
|
|
return status;
|
|
}
|
|
const SequenceNumber last_seq =
|
|
WriteBatchInternal::Sequence(&batch) +
|
|
WriteBatchInternal::Count(&batch) - 1;
|
|
if (last_seq > *max_sequence) {
|
|
*max_sequence = last_seq;
|
|
}
|
|
|
|
if (!read_only && mem_->ShouldFlush()) {
|
|
status = WriteLevel0TableForRecovery(mem_, &edit);
|
|
// we still want to clear memtable, even if the recovery failed
|
|
delete mem_->Unref();
|
|
mem_ = new MemTable(internal_comparator_, options_);
|
|
mem_->Ref();
|
|
memtable_empty = true;
|
|
if (!status.ok()) {
|
|
// Reflect errors immediately so that conditions like full
|
|
// file-systems cause the DB::Open() to fail.
|
|
return status;
|
|
}
|
|
}
|
|
}
|
|
|
|
if (!memtable_empty && !read_only) {
|
|
status = WriteLevel0TableForRecovery(mem_, &edit);
|
|
delete mem_->Unref();
|
|
mem_ = new MemTable(internal_comparator_, options_);
|
|
mem_->Ref();
|
|
if (!status.ok()) {
|
|
return status;
|
|
}
|
|
}
|
|
|
|
if (edit.NumEntries() > 0) {
|
|
// if read_only, NumEntries() will be 0
|
|
assert(!read_only);
|
|
// writing log number in the manifest means that any log file
|
|
// with number strongly less than (log_number + 1) is already
|
|
// recovered and should be ignored on next reincarnation.
|
|
// Since we already recovered log_number, we want all logs
|
|
// with numbers `<= log_number` (includes this one) to be ignored
|
|
edit.SetLogNumber(log_number + 1);
|
|
// we must mark the next log number as used, even though it's
|
|
// not actually used. that is because VersionSet assumes
|
|
// VersionSet::next_file_number_ always to be strictly greater than any log
|
|
// number
|
|
versions_->MarkFileNumberUsed(log_number + 1);
|
|
status = versions_->LogAndApply(&edit, &mutex_);
|
|
}
|
|
|
|
return status;
|
|
}
|
|
|
|
Status DBImpl::WriteLevel0TableForRecovery(MemTable* mem, VersionEdit* edit) {
|
|
mutex_.AssertHeld();
|
|
const uint64_t start_micros = env_->NowMicros();
|
|
FileMetaData meta;
|
|
meta.number = versions_->NewFileNumber();
|
|
pending_outputs_.insert(meta.number);
|
|
Iterator* iter = mem->NewIterator();
|
|
const SequenceNumber newest_snapshot = snapshots_.GetNewest();
|
|
const SequenceNumber earliest_seqno_in_memtable =
|
|
mem->GetFirstSequenceNumber();
|
|
Log(options_.info_log, "Level-0 table #%lu: started",
|
|
(unsigned long) meta.number);
|
|
|
|
Status s;
|
|
{
|
|
mutex_.Unlock();
|
|
s = BuildTable(dbname_, env_, options_, storage_options_,
|
|
table_cache_.get(), iter, &meta, internal_comparator_,
|
|
newest_snapshot, earliest_seqno_in_memtable,
|
|
GetCompressionFlush(options_));
|
|
LogFlush(options_.info_log);
|
|
mutex_.Lock();
|
|
}
|
|
|
|
Log(options_.info_log, "Level-0 table #%lu: %lu bytes %s",
|
|
(unsigned long) meta.number,
|
|
(unsigned long) meta.file_size,
|
|
s.ToString().c_str());
|
|
delete iter;
|
|
|
|
pending_outputs_.erase(meta.number);
|
|
|
|
// Note that if file_size is zero, the file has been deleted and
|
|
// should not be added to the manifest.
|
|
int level = 0;
|
|
if (s.ok() && meta.file_size > 0) {
|
|
edit->AddFile(level, meta.number, meta.file_size,
|
|
meta.smallest, meta.largest,
|
|
meta.smallest_seqno, meta.largest_seqno);
|
|
}
|
|
|
|
InternalStats::CompactionStats stats;
|
|
stats.micros = env_->NowMicros() - start_micros;
|
|
stats.bytes_written = meta.file_size;
|
|
stats.files_out_levelnp1 = 1;
|
|
internal_stats_.AddCompactionStats(level, stats);
|
|
RecordTick(options_.statistics.get(), COMPACT_WRITE_BYTES, meta.file_size);
|
|
return s;
|
|
}
|
|
|
|
|
|
Status DBImpl::WriteLevel0Table(autovector<MemTable*>& mems, VersionEdit* edit,
|
|
uint64_t* filenumber,
|
|
LogBuffer* log_buffer) {
|
|
mutex_.AssertHeld();
|
|
const uint64_t start_micros = env_->NowMicros();
|
|
FileMetaData meta;
|
|
meta.number = versions_->NewFileNumber();
|
|
*filenumber = meta.number;
|
|
pending_outputs_.insert(meta.number);
|
|
|
|
const SequenceNumber newest_snapshot = snapshots_.GetNewest();
|
|
const SequenceNumber earliest_seqno_in_memtable =
|
|
mems[0]->GetFirstSequenceNumber();
|
|
Version* base = versions_->current();
|
|
base->Ref(); // it is likely that we do not need this reference
|
|
Status s;
|
|
{
|
|
mutex_.Unlock();
|
|
log_buffer->FlushBufferToLog();
|
|
std::vector<Iterator*> memtables;
|
|
for (MemTable* m : mems) {
|
|
Log(options_.info_log,
|
|
"Flushing memtable with log file: %lu\n",
|
|
(unsigned long)m->GetLogNumber());
|
|
memtables.push_back(m->NewIterator());
|
|
}
|
|
Iterator* iter = NewMergingIterator(
|
|
env_, &internal_comparator_, &memtables[0], memtables.size());
|
|
Log(options_.info_log,
|
|
"Level-0 flush table #%lu: started",
|
|
(unsigned long)meta.number);
|
|
|
|
s = BuildTable(dbname_, env_, options_, storage_options_,
|
|
table_cache_.get(), iter, &meta, internal_comparator_,
|
|
newest_snapshot, earliest_seqno_in_memtable,
|
|
GetCompressionFlush(options_));
|
|
LogFlush(options_.info_log);
|
|
delete iter;
|
|
Log(options_.info_log, "Level-0 flush table #%lu: %lu bytes %s",
|
|
(unsigned long) meta.number,
|
|
(unsigned long) meta.file_size,
|
|
s.ToString().c_str());
|
|
if (!options_.disableDataSync) {
|
|
db_directory_->Fsync();
|
|
}
|
|
mutex_.Lock();
|
|
}
|
|
base->Unref();
|
|
|
|
// re-acquire the most current version
|
|
base = versions_->current();
|
|
|
|
// There could be multiple threads writing to its own level-0 file.
|
|
// The pending_outputs cannot be cleared here, otherwise this newly
|
|
// created file might not be considered as a live-file by another
|
|
// compaction thread that is concurrently deleting obselete files.
|
|
// The pending_outputs can be cleared only after the new version is
|
|
// committed so that other threads can recognize this file as a
|
|
// valid one.
|
|
// pending_outputs_.erase(meta.number);
|
|
|
|
// Note that if file_size is zero, the file has been deleted and
|
|
// should not be added to the manifest.
|
|
int level = 0;
|
|
if (s.ok() && meta.file_size > 0) {
|
|
const Slice min_user_key = meta.smallest.user_key();
|
|
const Slice max_user_key = meta.largest.user_key();
|
|
// if we have more than 1 background thread, then we cannot
|
|
// insert files directly into higher levels because some other
|
|
// threads could be concurrently producing compacted files for
|
|
// that key range.
|
|
if (base != nullptr && options_.max_background_compactions <= 1 &&
|
|
options_.compaction_style == kCompactionStyleLevel) {
|
|
level = base->PickLevelForMemTableOutput(min_user_key, max_user_key);
|
|
}
|
|
edit->AddFile(level, meta.number, meta.file_size,
|
|
meta.smallest, meta.largest,
|
|
meta.smallest_seqno, meta.largest_seqno);
|
|
}
|
|
|
|
InternalStats::CompactionStats stats;
|
|
stats.micros = env_->NowMicros() - start_micros;
|
|
stats.bytes_written = meta.file_size;
|
|
internal_stats_.AddCompactionStats(level, stats);
|
|
RecordTick(options_.statistics.get(), COMPACT_WRITE_BYTES, meta.file_size);
|
|
return s;
|
|
}
|
|
|
|
Status DBImpl::FlushMemTableToOutputFile(bool* madeProgress,
|
|
DeletionState& deletion_state,
|
|
LogBuffer* log_buffer) {
|
|
mutex_.AssertHeld();
|
|
assert(imm_.size() != 0);
|
|
assert(imm_.IsFlushPending());
|
|
|
|
// Save the contents of the earliest memtable as a new Table
|
|
uint64_t file_number;
|
|
autovector<MemTable*> mems;
|
|
imm_.PickMemtablesToFlush(&mems);
|
|
if (mems.empty()) {
|
|
LogToBuffer(log_buffer, "Nothing in memstore to flush");
|
|
return Status::OK();
|
|
}
|
|
|
|
// record the logfile_number_ before we release the mutex
|
|
// entries mems are (implicitly) sorted in ascending order by their created
|
|
// time. We will use the first memtable's `edit` to keep the meta info for
|
|
// this flush.
|
|
MemTable* m = mems[0];
|
|
VersionEdit* edit = m->GetEdits();
|
|
edit->SetPrevLogNumber(0);
|
|
// SetLogNumber(log_num) indicates logs with number smaller than log_num
|
|
// will no longer be picked up for recovery.
|
|
edit->SetLogNumber(
|
|
mems.back()->GetNextLogNumber()
|
|
);
|
|
|
|
std::vector<uint64_t> logs_to_delete;
|
|
for (auto mem : mems) {
|
|
logs_to_delete.push_back(mem->GetLogNumber());
|
|
}
|
|
|
|
// This will release and re-acquire the mutex.
|
|
Status s = WriteLevel0Table(mems, edit, &file_number, log_buffer);
|
|
|
|
if (s.ok() && shutting_down_.Acquire_Load()) {
|
|
s = Status::ShutdownInProgress(
|
|
"Database shutdown started during memtable compaction"
|
|
);
|
|
}
|
|
|
|
if (!s.ok()) {
|
|
imm_.RollbackMemtableFlush(mems, file_number, &pending_outputs_);
|
|
return s;
|
|
}
|
|
|
|
// Replace immutable memtable with the generated Table
|
|
s = imm_.InstallMemtableFlushResults(
|
|
mems, versions_.get(), &mutex_, options_.info_log.get(), file_number,
|
|
pending_outputs_, &deletion_state.memtables_to_free, db_directory_.get());
|
|
|
|
if (s.ok()) {
|
|
InstallSuperVersion(deletion_state);
|
|
if (madeProgress) {
|
|
*madeProgress = 1;
|
|
}
|
|
|
|
MaybeScheduleLogDBDeployStats();
|
|
|
|
if (disable_delete_obsolete_files_ == 0) {
|
|
// add to deletion state
|
|
deletion_state.log_delete_files.insert(
|
|
deletion_state.log_delete_files.end(),
|
|
logs_to_delete.begin(),
|
|
logs_to_delete.end());
|
|
}
|
|
}
|
|
return s;
|
|
}
|
|
|
|
Status DBImpl::CompactRange(const Slice* begin,
|
|
const Slice* end,
|
|
bool reduce_level,
|
|
int target_level) {
|
|
Status s = FlushMemTable(FlushOptions());
|
|
if (!s.ok()) {
|
|
LogFlush(options_.info_log);
|
|
return s;
|
|
}
|
|
|
|
int max_level_with_files = 1;
|
|
{
|
|
MutexLock l(&mutex_);
|
|
Version* base = versions_->current();
|
|
for (int level = 1; level < NumberLevels(); level++) {
|
|
if (base->OverlapInLevel(level, begin, end)) {
|
|
max_level_with_files = level;
|
|
}
|
|
}
|
|
}
|
|
for (int level = 0; level <= max_level_with_files; level++) {
|
|
// in case the compaction is unversal or if we're compacting the
|
|
// bottom-most level, the output level will be the same as input one
|
|
if (options_.compaction_style == kCompactionStyleUniversal ||
|
|
level == max_level_with_files) {
|
|
s = RunManualCompaction(level, level, begin, end);
|
|
} else {
|
|
s = RunManualCompaction(level, level + 1, begin, end);
|
|
}
|
|
if (!s.ok()) {
|
|
LogFlush(options_.info_log);
|
|
return s;
|
|
}
|
|
}
|
|
|
|
if (reduce_level) {
|
|
s = ReFitLevel(max_level_with_files, target_level);
|
|
}
|
|
LogFlush(options_.info_log);
|
|
|
|
return s;
|
|
}
|
|
|
|
// return the same level if it cannot be moved
|
|
int DBImpl::FindMinimumEmptyLevelFitting(int level) {
|
|
mutex_.AssertHeld();
|
|
Version* current = versions_->current();
|
|
int minimum_level = level;
|
|
for (int i = level - 1; i > 0; --i) {
|
|
// stop if level i is not empty
|
|
if (current->NumLevelFiles(i) > 0) break;
|
|
// stop if level i is too small (cannot fit the level files)
|
|
if (versions_->MaxBytesForLevel(i) < current->NumLevelBytes(level)) break;
|
|
|
|
minimum_level = i;
|
|
}
|
|
return minimum_level;
|
|
}
|
|
|
|
Status DBImpl::ReFitLevel(int level, int target_level) {
|
|
assert(level < NumberLevels());
|
|
|
|
SuperVersion* superversion_to_free = nullptr;
|
|
SuperVersion* new_superversion = new SuperVersion();
|
|
|
|
mutex_.Lock();
|
|
|
|
// only allow one thread refitting
|
|
if (refitting_level_) {
|
|
mutex_.Unlock();
|
|
Log(options_.info_log, "ReFitLevel: another thread is refitting");
|
|
delete new_superversion;
|
|
return Status::NotSupported("another thread is refitting");
|
|
}
|
|
refitting_level_ = true;
|
|
|
|
// wait for all background threads to stop
|
|
bg_work_gate_closed_ = true;
|
|
while (bg_compaction_scheduled_ > 0 || bg_flush_scheduled_) {
|
|
Log(options_.info_log,
|
|
"RefitLevel: waiting for background threads to stop: %d %d",
|
|
bg_compaction_scheduled_, bg_flush_scheduled_);
|
|
bg_cv_.Wait();
|
|
}
|
|
|
|
// move to a smaller level
|
|
int to_level = target_level;
|
|
if (target_level < 0) {
|
|
to_level = FindMinimumEmptyLevelFitting(level);
|
|
}
|
|
|
|
assert(to_level <= level);
|
|
|
|
Status status;
|
|
if (to_level < level) {
|
|
Log(options_.info_log, "Before refitting:\n%s",
|
|
versions_->current()->DebugString().data());
|
|
|
|
VersionEdit edit;
|
|
for (const auto& f : versions_->current()->files_[level]) {
|
|
edit.DeleteFile(level, f->number);
|
|
edit.AddFile(to_level, f->number, f->file_size, f->smallest, f->largest,
|
|
f->smallest_seqno, f->largest_seqno);
|
|
}
|
|
Log(options_.info_log, "Apply version edit:\n%s",
|
|
edit.DebugString().data());
|
|
|
|
status = versions_->LogAndApply(&edit, &mutex_, db_directory_.get());
|
|
superversion_to_free = InstallSuperVersion(new_superversion);
|
|
new_superversion = nullptr;
|
|
|
|
Log(options_.info_log, "LogAndApply: %s\n", status.ToString().data());
|
|
|
|
if (status.ok()) {
|
|
Log(options_.info_log, "After refitting:\n%s",
|
|
versions_->current()->DebugString().data());
|
|
}
|
|
}
|
|
|
|
refitting_level_ = false;
|
|
bg_work_gate_closed_ = false;
|
|
|
|
mutex_.Unlock();
|
|
delete superversion_to_free;
|
|
delete new_superversion;
|
|
return status;
|
|
}
|
|
|
|
int DBImpl::NumberLevels() {
|
|
return options_.num_levels;
|
|
}
|
|
|
|
int DBImpl::MaxMemCompactionLevel() {
|
|
return options_.max_mem_compaction_level;
|
|
}
|
|
|
|
int DBImpl::Level0StopWriteTrigger() {
|
|
return options_.level0_stop_writes_trigger;
|
|
}
|
|
|
|
uint64_t DBImpl::CurrentVersionNumber() const {
|
|
return super_version_number_.load();
|
|
}
|
|
|
|
Status DBImpl::Flush(const FlushOptions& options) {
|
|
return FlushMemTable(options);
|
|
}
|
|
|
|
SequenceNumber DBImpl::GetLatestSequenceNumber() const {
|
|
return versions_->LastSequence();
|
|
}
|
|
|
|
Status DBImpl::GetUpdatesSince(
|
|
SequenceNumber seq, unique_ptr<TransactionLogIterator>* iter,
|
|
const TransactionLogIterator::ReadOptions& read_options) {
|
|
|
|
RecordTick(options_.statistics.get(), GET_UPDATES_SINCE_CALLS);
|
|
if (seq > versions_->LastSequence()) {
|
|
return Status::NotFound(
|
|
"Requested sequence not yet written in the db");
|
|
}
|
|
// Get all sorted Wal Files.
|
|
// Do binary search and open files and find the seq number.
|
|
|
|
std::unique_ptr<VectorLogPtr> wal_files(new VectorLogPtr);
|
|
Status s = GetSortedWalFiles(*wal_files);
|
|
if (!s.ok()) {
|
|
return s;
|
|
}
|
|
|
|
s = RetainProbableWalFiles(*wal_files, seq);
|
|
if (!s.ok()) {
|
|
return s;
|
|
}
|
|
iter->reset(new TransactionLogIteratorImpl(options_.wal_dir, &options_,
|
|
read_options, storage_options_,
|
|
seq, std::move(wal_files), this));
|
|
return (*iter)->status();
|
|
}
|
|
|
|
Status DBImpl::RetainProbableWalFiles(VectorLogPtr& all_logs,
|
|
const SequenceNumber target) {
|
|
long start = 0; // signed to avoid overflow when target is < first file.
|
|
long end = static_cast<long>(all_logs.size()) - 1;
|
|
// Binary Search. avoid opening all files.
|
|
while (end >= start) {
|
|
long mid = start + (end - start) / 2; // Avoid overflow.
|
|
SequenceNumber current_seq_num = all_logs.at(mid)->StartSequence();
|
|
if (current_seq_num == target) {
|
|
end = mid;
|
|
break;
|
|
} else if (current_seq_num < target) {
|
|
start = mid + 1;
|
|
} else {
|
|
end = mid - 1;
|
|
}
|
|
}
|
|
size_t start_index = std::max(0l, end); // end could be -ve.
|
|
// The last wal file is always included
|
|
all_logs.erase(all_logs.begin(), all_logs.begin() + start_index);
|
|
return Status::OK();
|
|
}
|
|
|
|
bool DBImpl::CheckWalFileExistsAndEmpty(const WalFileType type,
|
|
const uint64_t number) {
|
|
const std::string fname = (type == kAliveLogFile) ?
|
|
LogFileName(options_.wal_dir, number) :
|
|
ArchivedLogFileName(options_.wal_dir, number);
|
|
uint64_t file_size;
|
|
Status s = env_->GetFileSize(fname, &file_size);
|
|
return (s.ok() && (file_size == 0));
|
|
}
|
|
|
|
Status DBImpl::ReadFirstRecord(const WalFileType type, const uint64_t number,
|
|
WriteBatch* const result) {
|
|
|
|
if (type == kAliveLogFile) {
|
|
std::string fname = LogFileName(options_.wal_dir, number);
|
|
Status status = ReadFirstLine(fname, result);
|
|
if (status.ok() || env_->FileExists(fname)) {
|
|
// return OK or any error that is not caused non-existing file
|
|
return status;
|
|
}
|
|
|
|
// check if the file got moved to archive.
|
|
std::string archived_file =
|
|
ArchivedLogFileName(options_.wal_dir, number);
|
|
Status s = ReadFirstLine(archived_file, result);
|
|
if (s.ok() || env_->FileExists(archived_file)) {
|
|
return s;
|
|
}
|
|
return Status::NotFound("Log File has been deleted: " + archived_file);
|
|
} else if (type == kArchivedLogFile) {
|
|
std::string fname = ArchivedLogFileName(options_.wal_dir, number);
|
|
Status status = ReadFirstLine(fname, result);
|
|
return status;
|
|
}
|
|
return Status::NotSupported("File Type Not Known: " + std::to_string(type));
|
|
}
|
|
|
|
Status DBImpl::ReadFirstLine(const std::string& fname,
|
|
WriteBatch* const batch) {
|
|
struct LogReporter : public log::Reader::Reporter {
|
|
Env* env;
|
|
Logger* info_log;
|
|
const char* fname;
|
|
|
|
Status* status;
|
|
bool ignore_error; // true if options_.paranoid_checks==false
|
|
virtual void Corruption(size_t bytes, const Status& s) {
|
|
Log(info_log, "%s%s: dropping %d bytes; %s",
|
|
(this->ignore_error ? "(ignoring error) " : ""),
|
|
fname, static_cast<int>(bytes), s.ToString().c_str());
|
|
if (this->status->ok()) {
|
|
// only keep the first error
|
|
*this->status = s;
|
|
}
|
|
}
|
|
};
|
|
|
|
unique_ptr<SequentialFile> file;
|
|
Status status = env_->NewSequentialFile(fname, &file, storage_options_);
|
|
|
|
if (!status.ok()) {
|
|
return status;
|
|
}
|
|
|
|
|
|
LogReporter reporter;
|
|
reporter.env = env_;
|
|
reporter.info_log = options_.info_log.get();
|
|
reporter.fname = fname.c_str();
|
|
reporter.status = &status;
|
|
reporter.ignore_error = !options_.paranoid_checks;
|
|
log::Reader reader(std::move(file), &reporter, true/*checksum*/,
|
|
0/*initial_offset*/);
|
|
std::string scratch;
|
|
Slice record;
|
|
|
|
if (reader.ReadRecord(&record, &scratch) &&
|
|
(status.ok() || !options_.paranoid_checks)) {
|
|
if (record.size() < 12) {
|
|
reporter.Corruption(
|
|
record.size(), Status::Corruption("log record too small"));
|
|
// TODO read record's till the first no corrupt entry?
|
|
} else {
|
|
WriteBatchInternal::SetContents(batch, record);
|
|
return Status::OK();
|
|
}
|
|
}
|
|
|
|
// ReadRecord returns false on EOF, which is deemed as OK() by Reader
|
|
if (status.ok()) {
|
|
status = Status::Corruption("eof reached");
|
|
}
|
|
return status;
|
|
}
|
|
|
|
struct CompareLogByPointer {
|
|
bool operator() (const unique_ptr<LogFile>& a,
|
|
const unique_ptr<LogFile>& b) {
|
|
LogFileImpl* a_impl = dynamic_cast<LogFileImpl*>(a.get());
|
|
LogFileImpl* b_impl = dynamic_cast<LogFileImpl*>(b.get());
|
|
return *a_impl < *b_impl;
|
|
}
|
|
};
|
|
|
|
Status DBImpl::AppendSortedWalsOfType(const std::string& path,
|
|
VectorLogPtr& log_files, WalFileType log_type) {
|
|
std::vector<std::string> all_files;
|
|
const Status status = env_->GetChildren(path, &all_files);
|
|
if (!status.ok()) {
|
|
return status;
|
|
}
|
|
log_files.reserve(log_files.size() + all_files.size());
|
|
VectorLogPtr::iterator pos_start;
|
|
if (!log_files.empty()) {
|
|
pos_start = log_files.end() - 1;
|
|
} else {
|
|
pos_start = log_files.begin();
|
|
}
|
|
for (const auto& f : all_files) {
|
|
uint64_t number;
|
|
FileType type;
|
|
if (ParseFileName(f, &number, &type) && type == kLogFile){
|
|
|
|
WriteBatch batch;
|
|
Status s = ReadFirstRecord(log_type, number, &batch);
|
|
if (!s.ok()) {
|
|
if (CheckWalFileExistsAndEmpty(log_type, number)) {
|
|
continue;
|
|
}
|
|
return s;
|
|
}
|
|
|
|
uint64_t size_bytes;
|
|
s = env_->GetFileSize(LogFileName(path, number), &size_bytes);
|
|
if (!s.ok()) {
|
|
return s;
|
|
}
|
|
|
|
log_files.push_back(std::move(unique_ptr<LogFile>(new LogFileImpl(
|
|
number, log_type, WriteBatchInternal::Sequence(&batch), size_bytes))));
|
|
}
|
|
}
|
|
CompareLogByPointer compare_log_files;
|
|
std::sort(pos_start, log_files.end(), compare_log_files);
|
|
return status;
|
|
}
|
|
|
|
Status DBImpl::RunManualCompaction(int input_level,
|
|
int output_level,
|
|
const Slice* begin,
|
|
const Slice* end) {
|
|
assert(input_level >= 0);
|
|
|
|
InternalKey begin_storage, end_storage;
|
|
|
|
ManualCompaction manual;
|
|
manual.input_level = input_level;
|
|
manual.output_level = output_level;
|
|
manual.done = false;
|
|
manual.in_progress = false;
|
|
// For universal compaction, we enforce every manual compaction to compact
|
|
// all files.
|
|
if (begin == nullptr ||
|
|
options_.compaction_style == kCompactionStyleUniversal) {
|
|
manual.begin = nullptr;
|
|
} else {
|
|
begin_storage = InternalKey(*begin, kMaxSequenceNumber, kValueTypeForSeek);
|
|
manual.begin = &begin_storage;
|
|
}
|
|
if (end == nullptr ||
|
|
options_.compaction_style == kCompactionStyleUniversal) {
|
|
manual.end = nullptr;
|
|
} else {
|
|
end_storage = InternalKey(*end, 0, static_cast<ValueType>(0));
|
|
manual.end = &end_storage;
|
|
}
|
|
|
|
MutexLock l(&mutex_);
|
|
|
|
// When a manual compaction arrives, temporarily disable scheduling of
|
|
// non-manual compactions and wait until the number of scheduled compaction
|
|
// jobs drops to zero. This is needed to ensure that this manual compaction
|
|
// can compact any range of keys/files.
|
|
//
|
|
// bg_manual_only_ is non-zero when at least one thread is inside
|
|
// RunManualCompaction(), i.e. during that time no other compaction will
|
|
// get scheduled (see MaybeScheduleFlushOrCompaction).
|
|
//
|
|
// Note that the following loop doesn't stop more that one thread calling
|
|
// RunManualCompaction() from getting to the second while loop below.
|
|
// However, only one of them will actually schedule compaction, while
|
|
// others will wait on a condition variable until it completes.
|
|
|
|
++bg_manual_only_;
|
|
while (bg_compaction_scheduled_ > 0) {
|
|
Log(options_.info_log,
|
|
"Manual compaction waiting for all other scheduled background "
|
|
"compactions to finish");
|
|
bg_cv_.Wait();
|
|
}
|
|
|
|
Log(options_.info_log, "Manual compaction starting");
|
|
|
|
while (!manual.done && !shutting_down_.Acquire_Load() && bg_error_.ok()) {
|
|
assert(bg_manual_only_ > 0);
|
|
if (manual_compaction_ != nullptr) {
|
|
// Running either this or some other manual compaction
|
|
bg_cv_.Wait();
|
|
} else {
|
|
manual_compaction_ = &manual;
|
|
MaybeScheduleFlushOrCompaction();
|
|
}
|
|
}
|
|
|
|
assert(!manual.in_progress);
|
|
assert(bg_manual_only_ > 0);
|
|
--bg_manual_only_;
|
|
return manual.status;
|
|
}
|
|
|
|
Status DBImpl::TEST_CompactRange(int level,
|
|
const Slice* begin,
|
|
const Slice* end) {
|
|
int output_level = (options_.compaction_style == kCompactionStyleUniversal)
|
|
? level
|
|
: level + 1;
|
|
return RunManualCompaction(level, output_level, begin, end);
|
|
}
|
|
|
|
Status DBImpl::FlushMemTable(const FlushOptions& options) {
|
|
// nullptr batch means just wait for earlier writes to be done
|
|
Status s = Write(WriteOptions(), nullptr);
|
|
if (s.ok() && options.wait) {
|
|
// Wait until the compaction completes
|
|
s = WaitForFlushMemTable();
|
|
}
|
|
return s;
|
|
}
|
|
|
|
Status DBImpl::WaitForFlushMemTable() {
|
|
Status s;
|
|
// Wait until the compaction completes
|
|
MutexLock l(&mutex_);
|
|
while (imm_.size() > 0 && bg_error_.ok()) {
|
|
bg_cv_.Wait();
|
|
}
|
|
if (imm_.size() != 0) {
|
|
s = bg_error_;
|
|
}
|
|
return s;
|
|
}
|
|
|
|
Status DBImpl::TEST_FlushMemTable(bool wait) {
|
|
FlushOptions fo;
|
|
fo.wait = wait;
|
|
return FlushMemTable(fo);
|
|
}
|
|
|
|
Status DBImpl::TEST_WaitForFlushMemTable() {
|
|
return WaitForFlushMemTable();
|
|
}
|
|
|
|
Status DBImpl::TEST_WaitForCompact() {
|
|
// Wait until the compaction completes
|
|
|
|
// TODO: a bug here. This function actually does not necessarily
|
|
// wait for compact. It actually waits for scheduled compaction
|
|
// OR flush to finish.
|
|
|
|
MutexLock l(&mutex_);
|
|
while ((bg_compaction_scheduled_ || bg_flush_scheduled_) &&
|
|
bg_error_.ok()) {
|
|
bg_cv_.Wait();
|
|
}
|
|
return bg_error_;
|
|
}
|
|
|
|
void DBImpl::MaybeScheduleFlushOrCompaction() {
|
|
mutex_.AssertHeld();
|
|
bg_schedule_needed_ = false;
|
|
if (bg_work_gate_closed_) {
|
|
// gate closed for backgrond work
|
|
} else if (shutting_down_.Acquire_Load()) {
|
|
// DB is being deleted; no more background compactions
|
|
} else {
|
|
bool is_flush_pending = imm_.IsFlushPending();
|
|
if (is_flush_pending) {
|
|
if (bg_flush_scheduled_ < options_.max_background_flushes) {
|
|
// memtable flush needed
|
|
bg_flush_scheduled_++;
|
|
env_->Schedule(&DBImpl::BGWorkFlush, this, Env::Priority::HIGH);
|
|
} else if (options_.max_background_flushes > 0) {
|
|
bg_schedule_needed_ = true;
|
|
}
|
|
}
|
|
|
|
// Schedule BGWorkCompaction if there's a compaction pending (or a memtable
|
|
// flush, but the HIGH pool is not enabled). Do it only if
|
|
// max_background_compactions hasn't been reached and, in case
|
|
// bg_manual_only_ > 0, if it's a manual compaction.
|
|
if ((manual_compaction_ ||
|
|
versions_->current()->NeedsCompaction() ||
|
|
(is_flush_pending && (options_.max_background_flushes <= 0))) &&
|
|
(!bg_manual_only_ || manual_compaction_)) {
|
|
if (bg_compaction_scheduled_ < options_.max_background_compactions) {
|
|
bg_compaction_scheduled_++;
|
|
env_->Schedule(&DBImpl::BGWorkCompaction, this, Env::Priority::LOW);
|
|
} else {
|
|
bg_schedule_needed_ = true;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
void DBImpl::BGWorkFlush(void* db) {
|
|
reinterpret_cast<DBImpl*>(db)->BackgroundCallFlush();
|
|
}
|
|
|
|
void DBImpl::BGWorkCompaction(void* db) {
|
|
reinterpret_cast<DBImpl*>(db)->BackgroundCallCompaction();
|
|
}
|
|
|
|
Status DBImpl::BackgroundFlush(bool* madeProgress,
|
|
DeletionState& deletion_state,
|
|
LogBuffer* log_buffer) {
|
|
Status stat;
|
|
while (stat.ok() && imm_.IsFlushPending()) {
|
|
Log(options_.info_log,
|
|
"BackgroundCallFlush doing FlushMemTableToOutputFile, flush slots available %d",
|
|
options_.max_background_flushes - bg_flush_scheduled_);
|
|
stat = FlushMemTableToOutputFile(madeProgress, deletion_state, log_buffer);
|
|
}
|
|
return stat;
|
|
}
|
|
|
|
void DBImpl::BackgroundCallFlush() {
|
|
bool madeProgress = false;
|
|
DeletionState deletion_state(true);
|
|
assert(bg_flush_scheduled_);
|
|
|
|
LogBuffer log_buffer(INFO, options_.info_log.get());
|
|
{
|
|
MutexLock l(&mutex_);
|
|
|
|
Status s;
|
|
if (!shutting_down_.Acquire_Load()) {
|
|
s = BackgroundFlush(&madeProgress, deletion_state, &log_buffer);
|
|
if (!s.ok()) {
|
|
// Wait a little bit before retrying background compaction in
|
|
// case this is an environmental problem and we do not want to
|
|
// chew up resources for failed compactions for the duration of
|
|
// the problem.
|
|
uint64_t error_cnt = internal_stats_.BumpAndGetBackgroundErrorCount();
|
|
bg_cv_.SignalAll(); // In case a waiter can proceed despite the error
|
|
mutex_.Unlock();
|
|
Log(options_.info_log,
|
|
"Waiting after background flush error: %s"
|
|
"Accumulated background error counts: %" PRIu64,
|
|
s.ToString().c_str(), error_cnt);
|
|
log_buffer.FlushBufferToLog();
|
|
LogFlush(options_.info_log);
|
|
env_->SleepForMicroseconds(1000000);
|
|
mutex_.Lock();
|
|
}
|
|
}
|
|
|
|
// If !s.ok(), this means that Flush failed. In that case, we want
|
|
// to delete all obsolete files and we force FindObsoleteFiles()
|
|
FindObsoleteFiles(deletion_state, !s.ok());
|
|
// delete unnecessary files if any, this is done outside the mutex
|
|
if (deletion_state.HaveSomethingToDelete() || !log_buffer.IsEmpty()) {
|
|
mutex_.Unlock();
|
|
// Have to flush the info logs before bg_flush_scheduled_--
|
|
// because if bg_flush_scheduled_ becomes 0 and the lock is
|
|
// released, the deconstructor of DB can kick in and destroy all the
|
|
// states of DB so info_log might not be available after that point.
|
|
// It also applies to access other states that DB owns.
|
|
log_buffer.FlushBufferToLog();
|
|
if (deletion_state.HaveSomethingToDelete()) {
|
|
PurgeObsoleteFiles(deletion_state);
|
|
}
|
|
mutex_.Lock();
|
|
}
|
|
|
|
bg_flush_scheduled_--;
|
|
// Any time the mutex is released After finding the work to do, another
|
|
// thread might execute MaybeScheduleFlushOrCompaction(). It is possible
|
|
// that there is a pending job but it is not scheduled because of the
|
|
// max thread limit.
|
|
if (madeProgress || bg_schedule_needed_) {
|
|
MaybeScheduleFlushOrCompaction();
|
|
}
|
|
bg_cv_.SignalAll();
|
|
// IMPORTANT: there should be no code after calling SignalAll. This call may
|
|
// signal the DB destructor that it's OK to proceed with destruction. In
|
|
// that case, all DB variables will be dealloacated and referencing them
|
|
// will cause trouble.
|
|
}
|
|
}
|
|
|
|
|
|
void DBImpl::TEST_PurgeObsoleteteWAL() {
|
|
PurgeObsoleteWALFiles();
|
|
}
|
|
|
|
uint64_t DBImpl::TEST_GetLevel0TotalSize() {
|
|
MutexLock l(&mutex_);
|
|
return versions_->current()->NumLevelBytes(0);
|
|
}
|
|
|
|
void DBImpl::BackgroundCallCompaction() {
|
|
bool madeProgress = false;
|
|
DeletionState deletion_state(true);
|
|
|
|
MaybeDumpStats();
|
|
LogBuffer log_buffer(INFO, options_.info_log.get());
|
|
{
|
|
MutexLock l(&mutex_);
|
|
// Log(options_.info_log, "XXX BG Thread %llx process new work item",
|
|
// pthread_self());
|
|
assert(bg_compaction_scheduled_);
|
|
Status s;
|
|
if (!shutting_down_.Acquire_Load()) {
|
|
s = BackgroundCompaction(&madeProgress, deletion_state, &log_buffer);
|
|
if (!s.ok()) {
|
|
// Wait a little bit before retrying background compaction in
|
|
// case this is an environmental problem and we do not want to
|
|
// chew up resources for failed compactions for the duration of
|
|
// the problem.
|
|
uint64_t error_cnt = internal_stats_.BumpAndGetBackgroundErrorCount();
|
|
bg_cv_.SignalAll(); // In case a waiter can proceed despite the error
|
|
mutex_.Unlock();
|
|
log_buffer.FlushBufferToLog();
|
|
Log(options_.info_log,
|
|
"Waiting after background compaction error: %s, "
|
|
"Accumulated background error counts: %" PRIu64,
|
|
s.ToString().c_str(), error_cnt);
|
|
LogFlush(options_.info_log);
|
|
env_->SleepForMicroseconds(1000000);
|
|
mutex_.Lock();
|
|
}
|
|
}
|
|
|
|
// If !s.ok(), this means that Compaction failed. In that case, we want
|
|
// to delete all obsolete files we might have created and we force
|
|
// FindObsoleteFiles(). This is because deletion_state does not catch
|
|
// all created files if compaction failed.
|
|
FindObsoleteFiles(deletion_state, !s.ok());
|
|
|
|
// delete unnecessary files if any, this is done outside the mutex
|
|
if (deletion_state.HaveSomethingToDelete() || !log_buffer.IsEmpty()) {
|
|
mutex_.Unlock();
|
|
// Have to flush the info logs before bg_compaction_scheduled_--
|
|
// because if bg_flush_scheduled_ becomes 0 and the lock is
|
|
// released, the deconstructor of DB can kick in and destroy all the
|
|
// states of DB so info_log might not be available after that point.
|
|
// It also applies to access other states that DB owns.
|
|
log_buffer.FlushBufferToLog();
|
|
if (deletion_state.HaveSomethingToDelete()) {
|
|
PurgeObsoleteFiles(deletion_state);
|
|
}
|
|
mutex_.Lock();
|
|
}
|
|
|
|
bg_compaction_scheduled_--;
|
|
|
|
MaybeScheduleLogDBDeployStats();
|
|
|
|
// Previous compaction may have produced too many files in a level,
|
|
// So reschedule another compaction if we made progress in the
|
|
// last compaction.
|
|
//
|
|
// Also, any time the mutex is released After finding the work to do,
|
|
// another thread might execute MaybeScheduleFlushOrCompaction(). It is
|
|
// possible that there is a pending job but it is not scheduled because of
|
|
// the max thread limit.
|
|
if (madeProgress || bg_schedule_needed_) {
|
|
MaybeScheduleFlushOrCompaction();
|
|
}
|
|
bg_cv_.SignalAll();
|
|
// IMPORTANT: there should be no code after calling SignalAll. This call may
|
|
// signal the DB destructor that it's OK to proceed with destruction. In
|
|
// that case, all DB variables will be dealloacated and referencing them
|
|
// will cause trouble.
|
|
}
|
|
}
|
|
|
|
Status DBImpl::BackgroundCompaction(bool* madeProgress,
|
|
DeletionState& deletion_state,
|
|
LogBuffer* log_buffer) {
|
|
*madeProgress = false;
|
|
mutex_.AssertHeld();
|
|
|
|
bool is_manual = (manual_compaction_ != nullptr) &&
|
|
(manual_compaction_->in_progress == false);
|
|
if (is_manual) {
|
|
// another thread cannot pick up the same work
|
|
manual_compaction_->in_progress = true;
|
|
}
|
|
|
|
// TODO: remove memtable flush from formal compaction
|
|
while (imm_.IsFlushPending()) {
|
|
LogToBuffer(log_buffer,
|
|
"BackgroundCompaction doing FlushMemTableToOutputFile, "
|
|
"compaction slots "
|
|
"available %d",
|
|
options_.max_background_compactions - bg_compaction_scheduled_);
|
|
Status stat = FlushMemTableToOutputFile(madeProgress, deletion_state,
|
|
log_buffer);
|
|
if (!stat.ok()) {
|
|
if (is_manual) {
|
|
manual_compaction_->status = stat;
|
|
manual_compaction_->done = true;
|
|
manual_compaction_->in_progress = false;
|
|
manual_compaction_ = nullptr;
|
|
}
|
|
return stat;
|
|
}
|
|
}
|
|
|
|
unique_ptr<Compaction> c;
|
|
InternalKey manual_end_storage;
|
|
InternalKey* manual_end = &manual_end_storage;
|
|
if (is_manual) {
|
|
ManualCompaction* m = manual_compaction_;
|
|
assert(m->in_progress);
|
|
c.reset(versions_->CompactRange(
|
|
m->input_level, m->output_level, m->begin, m->end, &manual_end));
|
|
if (!c) {
|
|
m->done = true;
|
|
}
|
|
LogToBuffer(
|
|
log_buffer,
|
|
"Manual compaction from level-%d to level-%d from %s .. %s; will stop "
|
|
"at %s\n",
|
|
m->input_level, m->output_level,
|
|
(m->begin ? m->begin->DebugString().c_str() : "(begin)"),
|
|
(m->end ? m->end->DebugString().c_str() : "(end)"),
|
|
((m->done || manual_end == nullptr)
|
|
? "(end)"
|
|
: manual_end->DebugString().c_str()));
|
|
} else if (!options_.disable_auto_compactions) {
|
|
c.reset(versions_->PickCompaction(log_buffer));
|
|
}
|
|
|
|
Status status;
|
|
if (!c) {
|
|
// Nothing to do
|
|
LogToBuffer(log_buffer, "Compaction nothing to do");
|
|
} else if (!is_manual && c->IsTrivialMove()) {
|
|
// Move file to next level
|
|
assert(c->num_input_files(0) == 1);
|
|
FileMetaData* f = c->input(0, 0);
|
|
c->edit()->DeleteFile(c->level(), f->number);
|
|
c->edit()->AddFile(c->level() + 1, f->number, f->file_size,
|
|
f->smallest, f->largest,
|
|
f->smallest_seqno, f->largest_seqno);
|
|
status = versions_->LogAndApply(c->edit(), &mutex_, db_directory_.get());
|
|
InstallSuperVersion(deletion_state);
|
|
Version::LevelSummaryStorage tmp;
|
|
LogToBuffer(log_buffer, "Moved #%lld to level-%d %lld bytes %s: %s\n",
|
|
static_cast<unsigned long long>(f->number), c->level() + 1,
|
|
static_cast<unsigned long long>(f->file_size),
|
|
status.ToString().c_str(),
|
|
versions_->current()->LevelSummary(&tmp));
|
|
versions_->ReleaseCompactionFiles(c.get(), status);
|
|
*madeProgress = true;
|
|
} else {
|
|
MaybeScheduleFlushOrCompaction(); // do more compaction work in parallel.
|
|
CompactionState* compact = new CompactionState(c.get());
|
|
status = DoCompactionWork(compact, deletion_state, log_buffer);
|
|
CleanupCompaction(compact, status);
|
|
versions_->ReleaseCompactionFiles(c.get(), status);
|
|
c->ReleaseInputs();
|
|
*madeProgress = true;
|
|
}
|
|
c.reset();
|
|
|
|
if (status.ok()) {
|
|
// Done
|
|
} else if (shutting_down_.Acquire_Load()) {
|
|
// Ignore compaction errors found during shutting down
|
|
} else {
|
|
Log(WARN, options_.info_log, "Compaction error: %s",
|
|
status.ToString().c_str());
|
|
if (options_.paranoid_checks && bg_error_.ok()) {
|
|
bg_error_ = status;
|
|
}
|
|
}
|
|
|
|
if (is_manual) {
|
|
ManualCompaction* m = manual_compaction_;
|
|
if (!status.ok()) {
|
|
m->status = status;
|
|
m->done = true;
|
|
}
|
|
// For universal compaction:
|
|
// Because universal compaction always happens at level 0, so one
|
|
// compaction will pick up all overlapped files. No files will be
|
|
// filtered out due to size limit and left for a successive compaction.
|
|
// So we can safely conclude the current compaction.
|
|
//
|
|
// Also note that, if we don't stop here, then the current compaction
|
|
// writes a new file back to level 0, which will be used in successive
|
|
// compaction. Hence the manual compaction will never finish.
|
|
//
|
|
// Stop the compaction if manual_end points to nullptr -- this means
|
|
// that we compacted the whole range. manual_end should always point
|
|
// to nullptr in case of universal compaction
|
|
if (manual_end == nullptr) {
|
|
m->done = true;
|
|
}
|
|
if (!m->done) {
|
|
// We only compacted part of the requested range. Update *m
|
|
// to the range that is left to be compacted.
|
|
// Universal compaction should always compact the whole range
|
|
assert(options_.compaction_style != kCompactionStyleUniversal);
|
|
m->tmp_storage = *manual_end;
|
|
m->begin = &m->tmp_storage;
|
|
}
|
|
m->in_progress = false; // not being processed anymore
|
|
manual_compaction_ = nullptr;
|
|
}
|
|
return status;
|
|
}
|
|
|
|
void DBImpl::CleanupCompaction(CompactionState* compact, Status status) {
|
|
mutex_.AssertHeld();
|
|
if (compact->builder != nullptr) {
|
|
// May happen if we get a shutdown call in the middle of compaction
|
|
compact->builder->Abandon();
|
|
compact->builder.reset();
|
|
} else {
|
|
assert(compact->outfile == nullptr);
|
|
}
|
|
for (size_t i = 0; i < compact->outputs.size(); i++) {
|
|
const CompactionState::Output& out = compact->outputs[i];
|
|
pending_outputs_.erase(out.number);
|
|
|
|
// If this file was inserted into the table cache then remove
|
|
// them here because this compaction was not committed.
|
|
if (!status.ok()) {
|
|
table_cache_->Evict(out.number);
|
|
}
|
|
}
|
|
delete compact;
|
|
}
|
|
|
|
// Allocate the file numbers for the output file. We allocate as
|
|
// many output file numbers as there are files in level+1 (at least one)
|
|
// Insert them into pending_outputs so that they do not get deleted.
|
|
void DBImpl::AllocateCompactionOutputFileNumbers(CompactionState* compact) {
|
|
mutex_.AssertHeld();
|
|
assert(compact != nullptr);
|
|
assert(compact->builder == nullptr);
|
|
int filesNeeded = compact->compaction->num_input_files(1);
|
|
for (int i = 0; i < std::max(filesNeeded, 1); i++) {
|
|
uint64_t file_number = versions_->NewFileNumber();
|
|
pending_outputs_.insert(file_number);
|
|
compact->allocated_file_numbers.push_back(file_number);
|
|
}
|
|
}
|
|
|
|
// Frees up unused file number.
|
|
void DBImpl::ReleaseCompactionUnusedFileNumbers(CompactionState* compact) {
|
|
mutex_.AssertHeld();
|
|
for (const auto file_number : compact->allocated_file_numbers) {
|
|
pending_outputs_.erase(file_number);
|
|
// Log(options_.info_log, "XXX releasing unused file num %d", file_number);
|
|
}
|
|
}
|
|
|
|
Status DBImpl::OpenCompactionOutputFile(CompactionState* compact) {
|
|
assert(compact != nullptr);
|
|
assert(compact->builder == nullptr);
|
|
uint64_t file_number;
|
|
// If we have not yet exhausted the pre-allocated file numbers,
|
|
// then use the one from the front. Otherwise, we have to acquire
|
|
// the heavyweight lock and allocate a new file number.
|
|
if (!compact->allocated_file_numbers.empty()) {
|
|
file_number = compact->allocated_file_numbers.front();
|
|
compact->allocated_file_numbers.pop_front();
|
|
} else {
|
|
mutex_.Lock();
|
|
file_number = versions_->NewFileNumber();
|
|
pending_outputs_.insert(file_number);
|
|
mutex_.Unlock();
|
|
}
|
|
CompactionState::Output out;
|
|
out.number = file_number;
|
|
out.smallest.Clear();
|
|
out.largest.Clear();
|
|
out.smallest_seqno = out.largest_seqno = 0;
|
|
compact->outputs.push_back(out);
|
|
|
|
// Make the output file
|
|
std::string fname = TableFileName(dbname_, file_number);
|
|
Status s = env_->NewWritableFile(fname, &compact->outfile, storage_options_);
|
|
|
|
if (s.ok()) {
|
|
// Over-estimate slightly so we don't end up just barely crossing
|
|
// the threshold.
|
|
compact->outfile->SetPreallocationBlockSize(
|
|
1.1 * versions_->MaxFileSizeForLevel(compact->compaction->output_level()));
|
|
|
|
CompressionType compression_type = GetCompressionType(
|
|
options_, compact->compaction->output_level(),
|
|
compact->compaction->enable_compression());
|
|
|
|
compact->builder.reset(NewTableBuilder(options_, internal_comparator_,
|
|
compact->outfile.get(),
|
|
compression_type));
|
|
}
|
|
LogFlush(options_.info_log);
|
|
return s;
|
|
}
|
|
|
|
Status DBImpl::FinishCompactionOutputFile(CompactionState* compact,
|
|
Iterator* input) {
|
|
assert(compact != nullptr);
|
|
assert(compact->outfile);
|
|
assert(compact->builder != nullptr);
|
|
|
|
const uint64_t output_number = compact->current_output()->number;
|
|
assert(output_number != 0);
|
|
|
|
// Check for iterator errors
|
|
Status s = input->status();
|
|
const uint64_t current_entries = compact->builder->NumEntries();
|
|
if (s.ok()) {
|
|
s = compact->builder->Finish();
|
|
} else {
|
|
compact->builder->Abandon();
|
|
}
|
|
const uint64_t current_bytes = compact->builder->FileSize();
|
|
compact->current_output()->file_size = current_bytes;
|
|
compact->total_bytes += current_bytes;
|
|
compact->builder.reset();
|
|
|
|
// Finish and check for file errors
|
|
if (s.ok() && !options_.disableDataSync) {
|
|
if (options_.use_fsync) {
|
|
StopWatch sw(env_, options_.statistics.get(),
|
|
COMPACTION_OUTFILE_SYNC_MICROS, false);
|
|
s = compact->outfile->Fsync();
|
|
} else {
|
|
StopWatch sw(env_, options_.statistics.get(),
|
|
COMPACTION_OUTFILE_SYNC_MICROS, false);
|
|
s = compact->outfile->Sync();
|
|
}
|
|
}
|
|
if (s.ok()) {
|
|
s = compact->outfile->Close();
|
|
}
|
|
compact->outfile.reset();
|
|
|
|
if (s.ok() && current_entries > 0) {
|
|
// Verify that the table is usable
|
|
FileMetaData meta(output_number, current_bytes);
|
|
Iterator* iter = table_cache_->NewIterator(ReadOptions(), storage_options_,
|
|
internal_comparator_, meta);
|
|
s = iter->status();
|
|
delete iter;
|
|
if (s.ok()) {
|
|
Log(options_.info_log,
|
|
"Generated table #%lu: %lu keys, %lu bytes",
|
|
(unsigned long) output_number,
|
|
(unsigned long) current_entries,
|
|
(unsigned long) current_bytes);
|
|
}
|
|
}
|
|
return s;
|
|
}
|
|
|
|
|
|
Status DBImpl::InstallCompactionResults(CompactionState* compact) {
|
|
mutex_.AssertHeld();
|
|
|
|
// paranoia: verify that the files that we started with
|
|
// still exist in the current version and in the same original level.
|
|
// This ensures that a concurrent compaction did not erroneously
|
|
// pick the same files to compact.
|
|
if (!versions_->VerifyCompactionFileConsistency(compact->compaction)) {
|
|
Log(options_.info_log, "Compaction %d@%d + %d@%d files aborted",
|
|
compact->compaction->num_input_files(0),
|
|
compact->compaction->level(),
|
|
compact->compaction->num_input_files(1),
|
|
compact->compaction->level() + 1);
|
|
return Status::Corruption("Compaction input files inconsistent");
|
|
}
|
|
|
|
Log(options_.info_log, "Compacted %d@%d + %d@%d files => %lld bytes",
|
|
compact->compaction->num_input_files(0),
|
|
compact->compaction->level(),
|
|
compact->compaction->num_input_files(1),
|
|
compact->compaction->level() + 1,
|
|
static_cast<long long>(compact->total_bytes));
|
|
|
|
// Add compaction outputs
|
|
compact->compaction->AddInputDeletions(compact->compaction->edit());
|
|
for (size_t i = 0; i < compact->outputs.size(); i++) {
|
|
const CompactionState::Output& out = compact->outputs[i];
|
|
compact->compaction->edit()->AddFile(
|
|
compact->compaction->output_level(), out.number, out.file_size,
|
|
out.smallest, out.largest, out.smallest_seqno, out.largest_seqno);
|
|
}
|
|
return versions_->LogAndApply(compact->compaction->edit(), &mutex_,
|
|
db_directory_.get());
|
|
}
|
|
|
|
//
|
|
// Given a sequence number, return the sequence number of the
|
|
// earliest snapshot that this sequence number is visible in.
|
|
// The snapshots themselves are arranged in ascending order of
|
|
// sequence numbers.
|
|
// Employ a sequential search because the total number of
|
|
// snapshots are typically small.
|
|
inline SequenceNumber DBImpl::findEarliestVisibleSnapshot(
|
|
SequenceNumber in, std::vector<SequenceNumber>& snapshots,
|
|
SequenceNumber* prev_snapshot) {
|
|
SequenceNumber prev __attribute__((unused)) = 0;
|
|
for (const auto cur : snapshots) {
|
|
assert(prev <= cur);
|
|
if (cur >= in) {
|
|
*prev_snapshot = prev;
|
|
return cur;
|
|
}
|
|
prev = cur; // assignment
|
|
assert(prev);
|
|
}
|
|
Log(options_.info_log,
|
|
"Looking for seqid %lu but maxseqid is %lu",
|
|
(unsigned long)in,
|
|
(unsigned long)snapshots[snapshots.size()-1]);
|
|
assert(0);
|
|
return 0;
|
|
}
|
|
|
|
Status DBImpl::DoCompactionWork(CompactionState* compact,
|
|
DeletionState& deletion_state,
|
|
LogBuffer* log_buffer) {
|
|
assert(compact);
|
|
int64_t imm_micros = 0; // Micros spent doing imm_ compactions
|
|
Log(options_.info_log,
|
|
"Compacting %d@%d + %d@%d files, score %.2f slots available %d",
|
|
compact->compaction->num_input_files(0),
|
|
compact->compaction->level(),
|
|
compact->compaction->num_input_files(1),
|
|
compact->compaction->output_level(),
|
|
compact->compaction->score(),
|
|
options_.max_background_compactions - bg_compaction_scheduled_);
|
|
char scratch[2345];
|
|
compact->compaction->Summary(scratch, sizeof(scratch));
|
|
Log(options_.info_log, "Compaction start summary: %s\n", scratch);
|
|
|
|
assert(versions_->current()->NumLevelFiles(compact->compaction->level()) > 0);
|
|
assert(compact->builder == nullptr);
|
|
assert(!compact->outfile);
|
|
|
|
SequenceNumber visible_at_tip = 0;
|
|
SequenceNumber earliest_snapshot;
|
|
SequenceNumber latest_snapshot = 0;
|
|
snapshots_.getAll(compact->existing_snapshots);
|
|
if (compact->existing_snapshots.size() == 0) {
|
|
// optimize for fast path if there are no snapshots
|
|
visible_at_tip = versions_->LastSequence();
|
|
earliest_snapshot = visible_at_tip;
|
|
} else {
|
|
latest_snapshot = compact->existing_snapshots.back();
|
|
// Add the current seqno as the 'latest' virtual
|
|
// snapshot to the end of this list.
|
|
compact->existing_snapshots.push_back(versions_->LastSequence());
|
|
earliest_snapshot = compact->existing_snapshots[0];
|
|
}
|
|
|
|
// Is this compaction producing files at the bottommost level?
|
|
bool bottommost_level = compact->compaction->BottomMostLevel();
|
|
|
|
// Allocate the output file numbers before we release the lock
|
|
AllocateCompactionOutputFileNumbers(compact);
|
|
|
|
// Release mutex while we're actually doing the compaction work
|
|
mutex_.Unlock();
|
|
// flush log buffer immediately after releasing the mutex
|
|
log_buffer->FlushBufferToLog();
|
|
|
|
const uint64_t start_micros = env_->NowMicros();
|
|
unique_ptr<Iterator> input(versions_->MakeInputIterator(compact->compaction));
|
|
input->SeekToFirst();
|
|
Status status;
|
|
ParsedInternalKey ikey;
|
|
std::string current_user_key;
|
|
bool has_current_user_key = false;
|
|
SequenceNumber last_sequence_for_key __attribute__((unused)) =
|
|
kMaxSequenceNumber;
|
|
SequenceNumber visible_in_snapshot = kMaxSequenceNumber;
|
|
std::string compaction_filter_value;
|
|
std::vector<char> delete_key; // for compaction filter
|
|
MergeHelper merge(user_comparator(), options_.merge_operator.get(),
|
|
options_.info_log.get(),
|
|
false /* internal key corruption is expected */);
|
|
auto compaction_filter = options_.compaction_filter;
|
|
std::unique_ptr<CompactionFilter> compaction_filter_from_factory = nullptr;
|
|
if (!compaction_filter) {
|
|
auto context = compact->GetFilterContext();
|
|
compaction_filter_from_factory =
|
|
options_.compaction_filter_factory->CreateCompactionFilter(context);
|
|
compaction_filter = compaction_filter_from_factory.get();
|
|
}
|
|
|
|
for (; input->Valid() && !shutting_down_.Acquire_Load(); ) {
|
|
// Prioritize immutable compaction work
|
|
// TODO: remove memtable flush from normal compaction work
|
|
if (imm_.imm_flush_needed.NoBarrier_Load() != nullptr) {
|
|
const uint64_t imm_start = env_->NowMicros();
|
|
LogFlush(options_.info_log);
|
|
mutex_.Lock();
|
|
if (imm_.IsFlushPending()) {
|
|
FlushMemTableToOutputFile(nullptr, deletion_state, log_buffer);
|
|
bg_cv_.SignalAll(); // Wakeup MakeRoomForWrite() if necessary
|
|
}
|
|
mutex_.Unlock();
|
|
log_buffer->FlushBufferToLog();
|
|
imm_micros += (env_->NowMicros() - imm_start);
|
|
}
|
|
|
|
Slice key = input->key();
|
|
Slice value = input->value();
|
|
|
|
if (compact->compaction->ShouldStopBefore(key) &&
|
|
compact->builder != nullptr) {
|
|
status = FinishCompactionOutputFile(compact, input.get());
|
|
if (!status.ok()) {
|
|
break;
|
|
}
|
|
}
|
|
|
|
// Handle key/value, add to state, etc.
|
|
bool drop = false;
|
|
bool current_entry_is_merging = false;
|
|
if (!ParseInternalKey(key, &ikey)) {
|
|
// Do not hide error keys
|
|
// TODO: error key stays in db forever? Figure out the intention/rationale
|
|
// v10 error v8 : we cannot hide v8 even though it's pretty obvious.
|
|
current_user_key.clear();
|
|
has_current_user_key = false;
|
|
last_sequence_for_key = kMaxSequenceNumber;
|
|
visible_in_snapshot = kMaxSequenceNumber;
|
|
} else {
|
|
if (!has_current_user_key ||
|
|
user_comparator()->Compare(ikey.user_key,
|
|
Slice(current_user_key)) != 0) {
|
|
// First occurrence of this user key
|
|
current_user_key.assign(ikey.user_key.data(), ikey.user_key.size());
|
|
has_current_user_key = true;
|
|
last_sequence_for_key = kMaxSequenceNumber;
|
|
visible_in_snapshot = kMaxSequenceNumber;
|
|
|
|
// apply the compaction filter to the first occurrence of the user key
|
|
if (compaction_filter &&
|
|
ikey.type == kTypeValue &&
|
|
(visible_at_tip || ikey.sequence > latest_snapshot)) {
|
|
// If the user has specified a compaction filter and the sequence
|
|
// number is greater than any external snapshot, then invoke the
|
|
// filter.
|
|
// If the return value of the compaction filter is true, replace
|
|
// the entry with a delete marker.
|
|
bool value_changed = false;
|
|
compaction_filter_value.clear();
|
|
bool to_delete =
|
|
compaction_filter->Filter(compact->compaction->level(),
|
|
ikey.user_key, value,
|
|
&compaction_filter_value,
|
|
&value_changed);
|
|
if (to_delete) {
|
|
// make a copy of the original key
|
|
delete_key.assign(key.data(), key.data() + key.size());
|
|
// convert it to a delete
|
|
UpdateInternalKey(&delete_key[0], delete_key.size(),
|
|
ikey.sequence, kTypeDeletion);
|
|
// anchor the key again
|
|
key = Slice(&delete_key[0], delete_key.size());
|
|
// needed because ikey is backed by key
|
|
ParseInternalKey(key, &ikey);
|
|
// no value associated with delete
|
|
value.clear();
|
|
RecordTick(options_.statistics.get(), COMPACTION_KEY_DROP_USER);
|
|
} else if (value_changed) {
|
|
value = compaction_filter_value;
|
|
}
|
|
}
|
|
|
|
}
|
|
|
|
// If there are no snapshots, then this kv affect visibility at tip.
|
|
// Otherwise, search though all existing snapshots to find
|
|
// the earlist snapshot that is affected by this kv.
|
|
SequenceNumber prev_snapshot = 0; // 0 means no previous snapshot
|
|
SequenceNumber visible = visible_at_tip ?
|
|
visible_at_tip :
|
|
findEarliestVisibleSnapshot(ikey.sequence,
|
|
compact->existing_snapshots,
|
|
&prev_snapshot);
|
|
|
|
if (visible_in_snapshot == visible) {
|
|
// If the earliest snapshot is which this key is visible in
|
|
// is the same as the visibily of a previous instance of the
|
|
// same key, then this kv is not visible in any snapshot.
|
|
// Hidden by an newer entry for same user key
|
|
// TODO: why not > ?
|
|
assert(last_sequence_for_key >= ikey.sequence);
|
|
drop = true; // (A)
|
|
RecordTick(options_.statistics.get(), COMPACTION_KEY_DROP_NEWER_ENTRY);
|
|
} else if (ikey.type == kTypeDeletion &&
|
|
ikey.sequence <= earliest_snapshot &&
|
|
compact->compaction->IsBaseLevelForKey(ikey.user_key)) {
|
|
// For this user key:
|
|
// (1) there is no data in higher levels
|
|
// (2) data in lower levels will have larger sequence numbers
|
|
// (3) data in layers that are being compacted here and have
|
|
// smaller sequence numbers will be dropped in the next
|
|
// few iterations of this loop (by rule (A) above).
|
|
// Therefore this deletion marker is obsolete and can be dropped.
|
|
drop = true;
|
|
RecordTick(options_.statistics.get(), COMPACTION_KEY_DROP_OBSOLETE);
|
|
} else if (ikey.type == kTypeMerge) {
|
|
// We know the merge type entry is not hidden, otherwise we would
|
|
// have hit (A)
|
|
// We encapsulate the merge related state machine in a different
|
|
// object to minimize change to the existing flow. Turn out this
|
|
// logic could also be nicely re-used for memtable flush purge
|
|
// optimization in BuildTable.
|
|
merge.MergeUntil(input.get(), prev_snapshot, bottommost_level,
|
|
options_.statistics.get());
|
|
current_entry_is_merging = true;
|
|
if (merge.IsSuccess()) {
|
|
// Successfully found Put/Delete/(end-of-key-range) while merging
|
|
// Get the merge result
|
|
key = merge.key();
|
|
ParseInternalKey(key, &ikey);
|
|
value = merge.value();
|
|
} else {
|
|
// Did not find a Put/Delete/(end-of-key-range) while merging
|
|
// We now have some stack of merge operands to write out.
|
|
// NOTE: key,value, and ikey are now referring to old entries.
|
|
// These will be correctly set below.
|
|
assert(!merge.keys().empty());
|
|
assert(merge.keys().size() == merge.values().size());
|
|
|
|
// Hack to make sure last_sequence_for_key is correct
|
|
ParseInternalKey(merge.keys().front(), &ikey);
|
|
}
|
|
}
|
|
|
|
last_sequence_for_key = ikey.sequence;
|
|
visible_in_snapshot = visible;
|
|
}
|
|
#if 0
|
|
Log(options_.info_log,
|
|
" Compact: %s, seq %d, type: %d %d, drop: %d, is_base: %d, "
|
|
"%d smallest_snapshot: %d level: %d bottommost %d",
|
|
ikey.user_key.ToString().c_str(),
|
|
(int)ikey.sequence, ikey.type, kTypeValue, drop,
|
|
compact->compaction->IsBaseLevelForKey(ikey.user_key),
|
|
(int)last_sequence_for_key, (int)earliest_snapshot,
|
|
compact->compaction->level(), bottommost_level);
|
|
#endif
|
|
|
|
if (!drop) {
|
|
// We may write a single key (e.g.: for Put/Delete or successful merge).
|
|
// Or we may instead have to write a sequence/list of keys.
|
|
// We have to write a sequence iff we have an unsuccessful merge
|
|
bool has_merge_list = current_entry_is_merging && !merge.IsSuccess();
|
|
const std::deque<std::string>* keys = nullptr;
|
|
const std::deque<std::string>* values = nullptr;
|
|
std::deque<std::string>::const_reverse_iterator key_iter;
|
|
std::deque<std::string>::const_reverse_iterator value_iter;
|
|
if (has_merge_list) {
|
|
keys = &merge.keys();
|
|
values = &merge.values();
|
|
key_iter = keys->rbegin(); // The back (*rbegin()) is the first key
|
|
value_iter = values->rbegin();
|
|
|
|
key = Slice(*key_iter);
|
|
value = Slice(*value_iter);
|
|
}
|
|
|
|
// If we have a list of keys to write, traverse the list.
|
|
// If we have a single key to write, simply write that key.
|
|
while (true) {
|
|
// Invariant: key,value,ikey will always be the next entry to write
|
|
char* kptr = (char*)key.data();
|
|
std::string kstr;
|
|
|
|
// Zeroing out the sequence number leads to better compression.
|
|
// If this is the bottommost level (no files in lower levels)
|
|
// and the earliest snapshot is larger than this seqno
|
|
// then we can squash the seqno to zero.
|
|
if (bottommost_level && ikey.sequence < earliest_snapshot &&
|
|
ikey.type != kTypeMerge) {
|
|
assert(ikey.type != kTypeDeletion);
|
|
// make a copy because updating in place would cause problems
|
|
// with the priority queue that is managing the input key iterator
|
|
kstr.assign(key.data(), key.size());
|
|
kptr = (char *)kstr.c_str();
|
|
UpdateInternalKey(kptr, key.size(), (uint64_t)0, ikey.type);
|
|
}
|
|
|
|
Slice newkey(kptr, key.size());
|
|
assert((key.clear(), 1)); // we do not need 'key' anymore
|
|
|
|
// Open output file if necessary
|
|
if (compact->builder == nullptr) {
|
|
status = OpenCompactionOutputFile(compact);
|
|
if (!status.ok()) {
|
|
break;
|
|
}
|
|
}
|
|
|
|
SequenceNumber seqno = GetInternalKeySeqno(newkey);
|
|
if (compact->builder->NumEntries() == 0) {
|
|
compact->current_output()->smallest.DecodeFrom(newkey);
|
|
compact->current_output()->smallest_seqno = seqno;
|
|
} else {
|
|
compact->current_output()->smallest_seqno =
|
|
std::min(compact->current_output()->smallest_seqno, seqno);
|
|
}
|
|
compact->current_output()->largest.DecodeFrom(newkey);
|
|
compact->builder->Add(newkey, value);
|
|
compact->current_output()->largest_seqno =
|
|
std::max(compact->current_output()->largest_seqno, seqno);
|
|
|
|
// Close output file if it is big enough
|
|
if (compact->builder->FileSize() >=
|
|
compact->compaction->MaxOutputFileSize()) {
|
|
status = FinishCompactionOutputFile(compact, input.get());
|
|
if (!status.ok()) {
|
|
break;
|
|
}
|
|
}
|
|
|
|
// If we have a list of entries, move to next element
|
|
// If we only had one entry, then break the loop.
|
|
if (has_merge_list) {
|
|
++key_iter;
|
|
++value_iter;
|
|
|
|
// If at end of list
|
|
if (key_iter == keys->rend() || value_iter == values->rend()) {
|
|
// Sanity Check: if one ends, then both end
|
|
assert(key_iter == keys->rend() && value_iter == values->rend());
|
|
break;
|
|
}
|
|
|
|
// Otherwise not at end of list. Update key, value, and ikey.
|
|
key = Slice(*key_iter);
|
|
value = Slice(*value_iter);
|
|
ParseInternalKey(key, &ikey);
|
|
|
|
} else{
|
|
// Only had one item to begin with (Put/Delete)
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
// MergeUntil has moved input to the next entry
|
|
if (!current_entry_is_merging) {
|
|
input->Next();
|
|
}
|
|
}
|
|
|
|
if (status.ok() && shutting_down_.Acquire_Load()) {
|
|
status = Status::ShutdownInProgress(
|
|
"Database shutdown started during compaction");
|
|
}
|
|
if (status.ok() && compact->builder != nullptr) {
|
|
status = FinishCompactionOutputFile(compact, input.get());
|
|
}
|
|
if (status.ok()) {
|
|
status = input->status();
|
|
}
|
|
input.reset();
|
|
|
|
if (!options_.disableDataSync) {
|
|
db_directory_->Fsync();
|
|
}
|
|
|
|
InternalStats::CompactionStats stats;
|
|
stats.micros = env_->NowMicros() - start_micros - imm_micros;
|
|
MeasureTime(options_.statistics.get(), COMPACTION_TIME, stats.micros);
|
|
stats.files_in_leveln = compact->compaction->num_input_files(0);
|
|
stats.files_in_levelnp1 = compact->compaction->num_input_files(1);
|
|
|
|
int num_output_files = compact->outputs.size();
|
|
if (compact->builder != nullptr) {
|
|
// An error occurred so ignore the last output.
|
|
assert(num_output_files > 0);
|
|
--num_output_files;
|
|
}
|
|
stats.files_out_levelnp1 = num_output_files;
|
|
|
|
for (int i = 0; i < compact->compaction->num_input_files(0); i++) {
|
|
stats.bytes_readn += compact->compaction->input(0, i)->file_size;
|
|
RecordTick(options_.statistics.get(), COMPACT_READ_BYTES,
|
|
compact->compaction->input(0, i)->file_size);
|
|
}
|
|
|
|
for (int i = 0; i < compact->compaction->num_input_files(1); i++) {
|
|
stats.bytes_readnp1 += compact->compaction->input(1, i)->file_size;
|
|
RecordTick(options_.statistics.get(), COMPACT_READ_BYTES,
|
|
compact->compaction->input(1, i)->file_size);
|
|
}
|
|
|
|
for (int i = 0; i < num_output_files; i++) {
|
|
stats.bytes_written += compact->outputs[i].file_size;
|
|
RecordTick(options_.statistics.get(), COMPACT_WRITE_BYTES,
|
|
compact->outputs[i].file_size);
|
|
}
|
|
|
|
LogFlush(options_.info_log);
|
|
mutex_.Lock();
|
|
internal_stats_.AddCompactionStats(compact->compaction->output_level(),
|
|
stats);
|
|
|
|
// if there were any unused file number (mostly in case of
|
|
// compaction error), free up the entry from pending_putputs
|
|
ReleaseCompactionUnusedFileNumbers(compact);
|
|
|
|
if (status.ok()) {
|
|
status = InstallCompactionResults(compact);
|
|
InstallSuperVersion(deletion_state);
|
|
}
|
|
Version::LevelSummaryStorage tmp;
|
|
Log(options_.info_log,
|
|
"compacted to: %s, %.1f MB/sec, level %d, files in(%d, %d) out(%d) "
|
|
"MB in(%.1f, %.1f) out(%.1f), read-write-amplify(%.1f) "
|
|
"write-amplify(%.1f) %s\n",
|
|
versions_->current()->LevelSummary(&tmp),
|
|
(stats.bytes_readn + stats.bytes_readnp1 + stats.bytes_written) /
|
|
(double)stats.micros,
|
|
compact->compaction->output_level(), stats.files_in_leveln,
|
|
stats.files_in_levelnp1, stats.files_out_levelnp1,
|
|
stats.bytes_readn / 1048576.0, stats.bytes_readnp1 / 1048576.0,
|
|
stats.bytes_written / 1048576.0,
|
|
(stats.bytes_written + stats.bytes_readnp1 + stats.bytes_readn) /
|
|
(double)stats.bytes_readn,
|
|
stats.bytes_written / (double)stats.bytes_readn,
|
|
status.ToString().c_str());
|
|
|
|
return status;
|
|
}
|
|
|
|
namespace {
|
|
struct IterState {
|
|
IterState(DBImpl* db, port::Mutex* mu, DBImpl::SuperVersion* super_version)
|
|
: db(db), mu(mu), super_version(super_version) {}
|
|
|
|
DBImpl* db;
|
|
port::Mutex* mu;
|
|
DBImpl::SuperVersion* super_version;
|
|
};
|
|
|
|
static void CleanupIteratorState(void* arg1, void* arg2) {
|
|
IterState* state = reinterpret_cast<IterState*>(arg1);
|
|
|
|
bool need_cleanup = state->super_version->Unref();
|
|
if (need_cleanup) {
|
|
DBImpl::DeletionState deletion_state;
|
|
|
|
state->mu->Lock();
|
|
state->super_version->Cleanup();
|
|
state->db->FindObsoleteFiles(deletion_state, false, true);
|
|
state->mu->Unlock();
|
|
|
|
delete state->super_version;
|
|
if (deletion_state.HaveSomethingToDelete()) {
|
|
state->db->PurgeObsoleteFiles(deletion_state);
|
|
}
|
|
}
|
|
|
|
delete state;
|
|
}
|
|
} // namespace
|
|
|
|
Iterator* DBImpl::NewInternalIterator(const ReadOptions& options,
|
|
SequenceNumber* latest_snapshot) {
|
|
mutex_.Lock();
|
|
*latest_snapshot = versions_->LastSequence();
|
|
SuperVersion* super_version = super_version_->Ref();
|
|
mutex_.Unlock();
|
|
|
|
std::vector<Iterator*> iterator_list;
|
|
// Collect iterator for mutable mem
|
|
iterator_list.push_back(super_version->mem->NewIterator(options));
|
|
// Collect all needed child iterators for immutable memtables
|
|
super_version->imm->AddIterators(options, &iterator_list);
|
|
// Collect iterators for files in L0 - Ln
|
|
super_version->current->AddIterators(options, storage_options_,
|
|
&iterator_list);
|
|
Iterator* internal_iter = NewMergingIterator(
|
|
env_, &internal_comparator_, &iterator_list[0], iterator_list.size());
|
|
|
|
IterState* cleanup = new IterState(this, &mutex_, super_version);
|
|
internal_iter->RegisterCleanup(CleanupIteratorState, cleanup, nullptr);
|
|
|
|
return internal_iter;
|
|
}
|
|
|
|
Iterator* DBImpl::TEST_NewInternalIterator() {
|
|
SequenceNumber ignored;
|
|
ReadOptions read_options;
|
|
// Use prefix_seek to make the test function more useful.
|
|
read_options.prefix_seek = true;
|
|
return NewInternalIterator(read_options, &ignored);
|
|
}
|
|
|
|
std::pair<Iterator*, Iterator*> DBImpl::GetTailingIteratorPair(
|
|
const ReadOptions& options,
|
|
uint64_t* superversion_number) {
|
|
|
|
mutex_.Lock();
|
|
SuperVersion* super_version = super_version_->Ref();
|
|
if (superversion_number != nullptr) {
|
|
*superversion_number = CurrentVersionNumber();
|
|
}
|
|
mutex_.Unlock();
|
|
|
|
Iterator* mutable_iter = super_version->mem->NewIterator(options);
|
|
// create a DBIter that only uses memtable content; see NewIterator()
|
|
mutable_iter = NewDBIterator(&dbname_, env_, options_, user_comparator(),
|
|
mutable_iter, kMaxSequenceNumber);
|
|
|
|
std::vector<Iterator*> list;
|
|
super_version->imm->AddIterators(options, &list);
|
|
super_version->current->AddIterators(options, storage_options_, &list);
|
|
Iterator* immutable_iter =
|
|
NewMergingIterator(env_, &internal_comparator_, &list[0], list.size());
|
|
|
|
// create a DBIter that only uses memtable content; see NewIterator()
|
|
immutable_iter = NewDBIterator(&dbname_, env_, options_, user_comparator(),
|
|
immutable_iter, kMaxSequenceNumber);
|
|
|
|
// register cleanups
|
|
mutable_iter->RegisterCleanup(CleanupIteratorState,
|
|
new IterState(this, &mutex_, super_version), nullptr);
|
|
|
|
// bump the ref one more time since it will be Unref'ed twice
|
|
immutable_iter->RegisterCleanup(CleanupIteratorState,
|
|
new IterState(this, &mutex_, super_version->Ref()), nullptr);
|
|
|
|
return std::make_pair(mutable_iter, immutable_iter);
|
|
}
|
|
|
|
int64_t DBImpl::TEST_MaxNextLevelOverlappingBytes() {
|
|
MutexLock l(&mutex_);
|
|
return versions_->current()->MaxNextLevelOverlappingBytes();
|
|
}
|
|
|
|
Status DBImpl::Get(const ReadOptions& options,
|
|
const Slice& key,
|
|
std::string* value) {
|
|
return GetImpl(options, key, value);
|
|
}
|
|
|
|
// DeletionState gets created and destructed outside of the lock -- we
|
|
// use this convinently to:
|
|
// * malloc one SuperVersion() outside of the lock -- new_superversion
|
|
// * delete SuperVersion()s outside of the lock -- superversions_to_free
|
|
//
|
|
// However, if InstallSuperVersion() gets called twice with the same,
|
|
// deletion_state, we can't reuse the SuperVersion() that got malloced because
|
|
// first call already used it. In that rare case, we take a hit and create a
|
|
// new SuperVersion() inside of the mutex.
|
|
void DBImpl::InstallSuperVersion(DeletionState& deletion_state) {
|
|
mutex_.AssertHeld();
|
|
// if new_superversion == nullptr, it means somebody already used it
|
|
SuperVersion* new_superversion =
|
|
(deletion_state.new_superversion != nullptr) ?
|
|
deletion_state.new_superversion : new SuperVersion();
|
|
SuperVersion* old_superversion = InstallSuperVersion(new_superversion);
|
|
deletion_state.new_superversion = nullptr;
|
|
deletion_state.superversions_to_free.push_back(old_superversion);
|
|
// Reset SuperVersions cached in thread local storage
|
|
if (options_.allow_thread_local) {
|
|
ResetThreadLocalSuperVersions(&deletion_state);
|
|
}
|
|
}
|
|
|
|
DBImpl::SuperVersion* DBImpl::InstallSuperVersion(
|
|
SuperVersion* new_superversion) {
|
|
mutex_.AssertHeld();
|
|
new_superversion->Init(mem_, imm_.current(), versions_->current());
|
|
SuperVersion* old_superversion = super_version_;
|
|
super_version_ = new_superversion;
|
|
super_version_->db = this;
|
|
++super_version_number_;
|
|
super_version_->version_number = super_version_number_;
|
|
|
|
if (old_superversion != nullptr && old_superversion->Unref()) {
|
|
old_superversion->Cleanup();
|
|
return old_superversion; // will let caller delete outside of mutex
|
|
}
|
|
return nullptr;
|
|
}
|
|
|
|
void DBImpl::ResetThreadLocalSuperVersions(DeletionState* deletion_state) {
|
|
mutex_.AssertHeld();
|
|
autovector<void*> sv_ptrs;
|
|
local_sv_->Scrape(&sv_ptrs, SuperVersion::kSVObsolete);
|
|
for (auto ptr : sv_ptrs) {
|
|
assert(ptr);
|
|
if (ptr == SuperVersion::kSVInUse) {
|
|
continue;
|
|
}
|
|
auto sv = static_cast<SuperVersion*>(ptr);
|
|
if (static_cast<SuperVersion*>(ptr)->Unref()) {
|
|
sv->Cleanup();
|
|
deletion_state->superversions_to_free.push_back(sv);
|
|
}
|
|
}
|
|
}
|
|
|
|
Status DBImpl::GetImpl(const ReadOptions& options,
|
|
const Slice& key,
|
|
std::string* value,
|
|
bool* value_found) {
|
|
Status s;
|
|
|
|
StopWatch sw(env_, options_.statistics.get(), DB_GET, false);
|
|
StopWatchNano snapshot_timer(env_, false);
|
|
StartPerfTimer(&snapshot_timer);
|
|
SequenceNumber snapshot;
|
|
|
|
if (options.snapshot != nullptr) {
|
|
snapshot = reinterpret_cast<const SnapshotImpl*>(options.snapshot)->number_;
|
|
} else {
|
|
snapshot = versions_->LastSequence();
|
|
}
|
|
|
|
// Acquire SuperVersion
|
|
SuperVersion* sv = nullptr;
|
|
if (LIKELY(options_.allow_thread_local)) {
|
|
// The SuperVersion is cached in thread local storage to avoid acquiring
|
|
// mutex when SuperVersion does not change since the last use. When a new
|
|
// SuperVersion is installed, the compaction or flush thread cleans up
|
|
// cached SuperVersion in all existing thread local storage. To avoid
|
|
// acquiring mutex for this operation, we use atomic Swap() on the thread
|
|
// local pointer to guarantee exclusive access. If the thread local pointer
|
|
// is being used while a new SuperVersion is installed, the cached
|
|
// SuperVersion can become stale. In that case, the background thread would
|
|
// have swapped in kSVObsolete. We re-check the value at the end of
|
|
// Get, with an atomic compare and swap. The superversion will be released
|
|
// if detected to be stale.
|
|
void* ptr = local_sv_->Swap(SuperVersion::kSVInUse);
|
|
// Invariant:
|
|
// (1) Scrape (always) installs kSVObsolete in ThreadLocal storage
|
|
// (2) the Swap above (always) installs kSVInUse, ThreadLocal storage
|
|
// should only keep kSVInUse during a GetImpl.
|
|
assert(ptr != SuperVersion::kSVInUse);
|
|
sv = static_cast<SuperVersion*>(ptr);
|
|
if (sv == SuperVersion::kSVObsolete ||
|
|
sv->version_number != super_version_number_.load(
|
|
std::memory_order_relaxed)) {
|
|
RecordTick(options_.statistics.get(), NUMBER_SUPERVERSION_ACQUIRES);
|
|
SuperVersion* sv_to_delete = nullptr;
|
|
|
|
if (sv && sv->Unref()) {
|
|
RecordTick(options_.statistics.get(), NUMBER_SUPERVERSION_CLEANUPS);
|
|
mutex_.Lock();
|
|
// TODO underlying resources held by superversion (sst files) might
|
|
// not be released until the next background job.
|
|
sv->Cleanup();
|
|
sv_to_delete = sv;
|
|
} else {
|
|
mutex_.Lock();
|
|
}
|
|
sv = super_version_->Ref();
|
|
mutex_.Unlock();
|
|
|
|
delete sv_to_delete;
|
|
}
|
|
} else {
|
|
mutex_.Lock();
|
|
sv = super_version_->Ref();
|
|
mutex_.Unlock();
|
|
}
|
|
|
|
bool have_stat_update = false;
|
|
Version::GetStats stats;
|
|
|
|
// Prepare to store a list of merge operations if merge occurs.
|
|
MergeContext merge_context;
|
|
|
|
// First look in the memtable, then in the immutable memtable (if any).
|
|
// s is both in/out. When in, s could either be OK or MergeInProgress.
|
|
// merge_operands will contain the sequence of merges in the latter case.
|
|
LookupKey lkey(key, snapshot);
|
|
BumpPerfTime(&perf_context.get_snapshot_time, &snapshot_timer);
|
|
if (sv->mem->Get(lkey, value, &s, merge_context, options_)) {
|
|
// Done
|
|
RecordTick(options_.statistics.get(), MEMTABLE_HIT);
|
|
} else if (sv->imm->Get(lkey, value, &s, merge_context, options_)) {
|
|
// Done
|
|
RecordTick(options_.statistics.get(), MEMTABLE_HIT);
|
|
} else {
|
|
StopWatchNano from_files_timer(env_, false);
|
|
StartPerfTimer(&from_files_timer);
|
|
|
|
sv->current->Get(options, lkey, value, &s, &merge_context, &stats,
|
|
options_, value_found);
|
|
have_stat_update = true;
|
|
BumpPerfTime(&perf_context.get_from_output_files_time, &from_files_timer);
|
|
RecordTick(options_.statistics.get(), MEMTABLE_MISS);
|
|
}
|
|
|
|
StopWatchNano post_process_timer(env_, false);
|
|
StartPerfTimer(&post_process_timer);
|
|
|
|
if (!options_.disable_seek_compaction && have_stat_update) {
|
|
mutex_.Lock();
|
|
if (sv->current->UpdateStats(stats)) {
|
|
MaybeScheduleFlushOrCompaction();
|
|
}
|
|
mutex_.Unlock();
|
|
}
|
|
|
|
bool unref_sv = true;
|
|
if (LIKELY(options_.allow_thread_local)) {
|
|
// Put the SuperVersion back
|
|
void* expected = SuperVersion::kSVInUse;
|
|
if (local_sv_->CompareAndSwap(static_cast<void*>(sv), expected)) {
|
|
// When we see kSVInUse in the ThreadLocal, we are sure ThreadLocal
|
|
// storage has not been altered and no Scrape has happend. The
|
|
// SuperVersion is still current.
|
|
unref_sv = false;
|
|
} else {
|
|
// ThreadLocal scrape happened in the process of this GetImpl call (after
|
|
// thread local Swap() at the beginning and before CompareAndSwap()).
|
|
// This means the SuperVersion it holds is obsolete.
|
|
assert(expected == SuperVersion::kSVObsolete);
|
|
}
|
|
}
|
|
|
|
if (unref_sv) {
|
|
// Release SuperVersion
|
|
if (sv->Unref()) {
|
|
mutex_.Lock();
|
|
sv->Cleanup();
|
|
mutex_.Unlock();
|
|
delete sv;
|
|
RecordTick(options_.statistics.get(), NUMBER_SUPERVERSION_CLEANUPS);
|
|
}
|
|
RecordTick(options_.statistics.get(), NUMBER_SUPERVERSION_RELEASES);
|
|
}
|
|
|
|
// Note, tickers are atomic now - no lock protection needed any more.
|
|
RecordTick(options_.statistics.get(), NUMBER_KEYS_READ);
|
|
RecordTick(options_.statistics.get(), BYTES_READ, value->size());
|
|
BumpPerfTime(&perf_context.get_post_process_time, &post_process_timer);
|
|
return s;
|
|
}
|
|
|
|
std::vector<Status> DBImpl::MultiGet(const ReadOptions& options,
|
|
const std::vector<Slice>& keys,
|
|
std::vector<std::string>* values) {
|
|
StopWatch sw(env_, options_.statistics.get(), DB_MULTIGET, false);
|
|
StopWatchNano snapshot_timer(env_, false);
|
|
StartPerfTimer(&snapshot_timer);
|
|
|
|
SequenceNumber snapshot;
|
|
|
|
mutex_.Lock();
|
|
if (options.snapshot != nullptr) {
|
|
snapshot = reinterpret_cast<const SnapshotImpl*>(options.snapshot)->number_;
|
|
} else {
|
|
snapshot = versions_->LastSequence();
|
|
}
|
|
|
|
SuperVersion* get_version = super_version_->Ref();
|
|
mutex_.Unlock();
|
|
|
|
bool have_stat_update = false;
|
|
Version::GetStats stats;
|
|
|
|
// Contain a list of merge operations if merge occurs.
|
|
MergeContext merge_context;
|
|
|
|
// Note: this always resizes the values array
|
|
int numKeys = keys.size();
|
|
std::vector<Status> statList(numKeys);
|
|
values->resize(numKeys);
|
|
|
|
// Keep track of bytes that we read for statistics-recording later
|
|
uint64_t bytesRead = 0;
|
|
BumpPerfTime(&perf_context.get_snapshot_time, &snapshot_timer);
|
|
|
|
// For each of the given keys, apply the entire "get" process as follows:
|
|
// First look in the memtable, then in the immutable memtable (if any).
|
|
// s is both in/out. When in, s could either be OK or MergeInProgress.
|
|
// merge_operands will contain the sequence of merges in the latter case.
|
|
for (int i=0; i<numKeys; ++i) {
|
|
merge_context.Clear();
|
|
Status& s = statList[i];
|
|
std::string* value = &(*values)[i];
|
|
|
|
LookupKey lkey(keys[i], snapshot);
|
|
if (get_version->mem->Get(lkey, value, &s, merge_context, options_)) {
|
|
// Done
|
|
} else if (get_version->imm->Get(lkey, value, &s, merge_context,
|
|
options_)) {
|
|
// Done
|
|
} else {
|
|
get_version->current->Get(options, lkey, value, &s, &merge_context,
|
|
&stats, options_);
|
|
have_stat_update = true;
|
|
}
|
|
|
|
if (s.ok()) {
|
|
bytesRead += value->size();
|
|
}
|
|
}
|
|
|
|
// Post processing (decrement reference counts and record statistics)
|
|
StopWatchNano post_process_timer(env_, false);
|
|
StartPerfTimer(&post_process_timer);
|
|
bool delete_get_version = false;
|
|
if (!options_.disable_seek_compaction && have_stat_update) {
|
|
mutex_.Lock();
|
|
if (get_version->current->UpdateStats(stats)) {
|
|
MaybeScheduleFlushOrCompaction();
|
|
}
|
|
if (get_version->Unref()) {
|
|
get_version->Cleanup();
|
|
delete_get_version = true;
|
|
}
|
|
mutex_.Unlock();
|
|
} else {
|
|
if (get_version->Unref()) {
|
|
mutex_.Lock();
|
|
get_version->Cleanup();
|
|
mutex_.Unlock();
|
|
delete_get_version = true;
|
|
}
|
|
}
|
|
if (delete_get_version) {
|
|
delete get_version;
|
|
}
|
|
|
|
RecordTick(options_.statistics.get(), NUMBER_MULTIGET_CALLS);
|
|
RecordTick(options_.statistics.get(), NUMBER_MULTIGET_KEYS_READ, numKeys);
|
|
RecordTick(options_.statistics.get(), NUMBER_MULTIGET_BYTES_READ, bytesRead);
|
|
BumpPerfTime(&perf_context.get_post_process_time, &post_process_timer);
|
|
|
|
return statList;
|
|
}
|
|
|
|
bool DBImpl::KeyMayExist(const ReadOptions& options,
|
|
const Slice& key,
|
|
std::string* value,
|
|
bool* value_found) {
|
|
if (value_found != nullptr) {
|
|
// falsify later if key-may-exist but can't fetch value
|
|
*value_found = true;
|
|
}
|
|
ReadOptions roptions = options;
|
|
roptions.read_tier = kBlockCacheTier; // read from block cache only
|
|
auto s = GetImpl(roptions, key, value, value_found);
|
|
|
|
// If options.block_cache != nullptr and the index block of the table didn't
|
|
// not present in block_cache, the return value will be Status::Incomplete.
|
|
// In this case, key may still exist in the table.
|
|
return s.ok() || s.IsIncomplete();
|
|
}
|
|
|
|
Iterator* DBImpl::NewIterator(const ReadOptions& options) {
|
|
Iterator* iter;
|
|
|
|
if (options.tailing) {
|
|
iter = new TailingIterator(this, options, user_comparator());
|
|
} else {
|
|
SequenceNumber latest_snapshot;
|
|
iter = NewInternalIterator(options, &latest_snapshot);
|
|
|
|
iter = NewDBIterator(
|
|
&dbname_, env_, options_, user_comparator(), iter,
|
|
(options.snapshot != nullptr
|
|
? reinterpret_cast<const SnapshotImpl*>(options.snapshot)->number_
|
|
: latest_snapshot));
|
|
}
|
|
|
|
if (options.prefix) {
|
|
// use extra wrapper to exclude any keys from the results which
|
|
// don't begin with the prefix
|
|
iter = new PrefixFilterIterator(iter, *options.prefix,
|
|
options_.prefix_extractor.get());
|
|
}
|
|
return iter;
|
|
}
|
|
|
|
const Snapshot* DBImpl::GetSnapshot() {
|
|
MutexLock l(&mutex_);
|
|
return snapshots_.New(versions_->LastSequence());
|
|
}
|
|
|
|
void DBImpl::ReleaseSnapshot(const Snapshot* s) {
|
|
MutexLock l(&mutex_);
|
|
snapshots_.Delete(reinterpret_cast<const SnapshotImpl*>(s));
|
|
}
|
|
|
|
// Convenience methods
|
|
Status DBImpl::Put(const WriteOptions& o, const Slice& key, const Slice& val) {
|
|
return DB::Put(o, key, val);
|
|
}
|
|
|
|
Status DBImpl::Merge(const WriteOptions& o, const Slice& key,
|
|
const Slice& val) {
|
|
if (!options_.merge_operator) {
|
|
return Status::NotSupported("Provide a merge_operator when opening DB");
|
|
} else {
|
|
return DB::Merge(o, key, val);
|
|
}
|
|
}
|
|
|
|
Status DBImpl::Delete(const WriteOptions& options, const Slice& key) {
|
|
return DB::Delete(options, key);
|
|
}
|
|
|
|
Status DBImpl::Write(const WriteOptions& options, WriteBatch* my_batch) {
|
|
StopWatchNano pre_post_process_timer(env_, false);
|
|
StartPerfTimer(&pre_post_process_timer);
|
|
Writer w(&mutex_);
|
|
w.batch = my_batch;
|
|
w.sync = options.sync;
|
|
w.disableWAL = options.disableWAL;
|
|
w.done = false;
|
|
|
|
StopWatch sw(env_, options_.statistics.get(), DB_WRITE, false);
|
|
mutex_.Lock();
|
|
writers_.push_back(&w);
|
|
while (!w.done && &w != writers_.front()) {
|
|
w.cv.Wait();
|
|
}
|
|
|
|
if (!options.disableWAL) {
|
|
RecordTick(options_.statistics.get(), WRITE_WITH_WAL, 1);
|
|
}
|
|
|
|
if (w.done) {
|
|
mutex_.Unlock();
|
|
RecordTick(options_.statistics.get(), WRITE_DONE_BY_OTHER, 1);
|
|
return w.status;
|
|
} else {
|
|
RecordTick(options_.statistics.get(), WRITE_DONE_BY_SELF, 1);
|
|
}
|
|
|
|
// May temporarily unlock and wait.
|
|
SuperVersion* superversion_to_free = nullptr;
|
|
Status status = MakeRoomForWrite(my_batch == nullptr, &superversion_to_free);
|
|
uint64_t last_sequence = versions_->LastSequence();
|
|
Writer* last_writer = &w;
|
|
if (status.ok() && my_batch != nullptr) { // nullptr batch is for compactions
|
|
autovector<WriteBatch*> write_batch_group;
|
|
BuildBatchGroup(&last_writer, &write_batch_group);
|
|
|
|
// Add to log and apply to memtable. We can release the lock
|
|
// during this phase since &w is currently responsible for logging
|
|
// and protects against concurrent loggers and concurrent writes
|
|
// into mem_.
|
|
{
|
|
mutex_.Unlock();
|
|
WriteBatch* updates = nullptr;
|
|
if (write_batch_group.size() == 1) {
|
|
updates = write_batch_group[0];
|
|
} else {
|
|
updates = &tmp_batch_;
|
|
for (size_t i = 0; i < write_batch_group.size(); ++i) {
|
|
WriteBatchInternal::Append(updates, write_batch_group[i]);
|
|
}
|
|
}
|
|
|
|
const SequenceNumber current_sequence = last_sequence + 1;
|
|
WriteBatchInternal::SetSequence(updates, current_sequence);
|
|
int my_batch_count = WriteBatchInternal::Count(updates);
|
|
last_sequence += my_batch_count;
|
|
// Record statistics
|
|
RecordTick(options_.statistics.get(),
|
|
NUMBER_KEYS_WRITTEN, my_batch_count);
|
|
RecordTick(options_.statistics.get(),
|
|
BYTES_WRITTEN,
|
|
WriteBatchInternal::ByteSize(updates));
|
|
if (options.disableWAL) {
|
|
flush_on_destroy_ = true;
|
|
}
|
|
BumpPerfTime(&perf_context.write_pre_and_post_process_time,
|
|
&pre_post_process_timer);
|
|
|
|
if (!options.disableWAL) {
|
|
StopWatchNano timer(env_);
|
|
StartPerfTimer(&timer);
|
|
Slice log_entry = WriteBatchInternal::Contents(updates);
|
|
status = log_->AddRecord(log_entry);
|
|
RecordTick(options_.statistics.get(), WAL_FILE_SYNCED, 1);
|
|
RecordTick(options_.statistics.get(), WAL_FILE_BYTES, log_entry.size());
|
|
if (status.ok() && options.sync) {
|
|
if (options_.use_fsync) {
|
|
StopWatch(env_, options_.statistics.get(), WAL_FILE_SYNC_MICROS);
|
|
status = log_->file()->Fsync();
|
|
} else {
|
|
StopWatch(env_, options_.statistics.get(), WAL_FILE_SYNC_MICROS);
|
|
status = log_->file()->Sync();
|
|
}
|
|
}
|
|
BumpPerfTime(&perf_context.write_wal_time, &timer);
|
|
}
|
|
if (status.ok()) {
|
|
StopWatchNano write_memtable_timer(env_, false);
|
|
StartPerfTimer(&write_memtable_timer);
|
|
status = WriteBatchInternal::InsertInto(updates, mem_, &options_, this,
|
|
options_.filter_deletes);
|
|
BumpPerfTime(&perf_context.write_memtable_time, &write_memtable_timer);
|
|
if (!status.ok()) {
|
|
// Panic for in-memory corruptions
|
|
// Note that existing logic was not sound. Any partial failure writing
|
|
// into the memtable would result in a state that some write ops might
|
|
// have succeeded in memtable but Status reports error for all writes.
|
|
throw std::runtime_error("In memory WriteBatch corruption!");
|
|
}
|
|
SetTickerCount(options_.statistics.get(), SEQUENCE_NUMBER,
|
|
last_sequence);
|
|
}
|
|
StartPerfTimer(&pre_post_process_timer);
|
|
if (updates == &tmp_batch_) tmp_batch_.Clear();
|
|
mutex_.Lock();
|
|
if (status.ok()) {
|
|
versions_->SetLastSequence(last_sequence);
|
|
}
|
|
}
|
|
}
|
|
if (options_.paranoid_checks && !status.ok() && bg_error_.ok()) {
|
|
bg_error_ = status; // stop compaction & fail any further writes
|
|
}
|
|
|
|
while (true) {
|
|
Writer* ready = writers_.front();
|
|
writers_.pop_front();
|
|
if (ready != &w) {
|
|
ready->status = status;
|
|
ready->done = true;
|
|
ready->cv.Signal();
|
|
}
|
|
if (ready == last_writer) break;
|
|
}
|
|
|
|
// Notify new head of write queue
|
|
if (!writers_.empty()) {
|
|
writers_.front()->cv.Signal();
|
|
}
|
|
mutex_.Unlock();
|
|
delete superversion_to_free;
|
|
BumpPerfTime(&perf_context.write_pre_and_post_process_time,
|
|
&pre_post_process_timer);
|
|
return status;
|
|
}
|
|
|
|
// REQUIRES: Writer list must be non-empty
|
|
// REQUIRES: First writer must have a non-nullptr batch
|
|
void DBImpl::BuildBatchGroup(Writer** last_writer,
|
|
autovector<WriteBatch*>* write_batch_group) {
|
|
assert(!writers_.empty());
|
|
Writer* first = writers_.front();
|
|
assert(first->batch != nullptr);
|
|
|
|
size_t size = WriteBatchInternal::ByteSize(first->batch);
|
|
write_batch_group->push_back(first->batch);
|
|
|
|
// Allow the group to grow up to a maximum size, but if the
|
|
// original write is small, limit the growth so we do not slow
|
|
// down the small write too much.
|
|
size_t max_size = 1 << 20;
|
|
if (size <= (128<<10)) {
|
|
max_size = size + (128<<10);
|
|
}
|
|
|
|
*last_writer = first;
|
|
std::deque<Writer*>::iterator iter = writers_.begin();
|
|
++iter; // Advance past "first"
|
|
for (; iter != writers_.end(); ++iter) {
|
|
Writer* w = *iter;
|
|
if (w->sync && !first->sync) {
|
|
// Do not include a sync write into a batch handled by a non-sync write.
|
|
break;
|
|
}
|
|
|
|
if (!w->disableWAL && first->disableWAL) {
|
|
// Do not include a write that needs WAL into a batch that has
|
|
// WAL disabled.
|
|
break;
|
|
}
|
|
|
|
if (w->batch != nullptr) {
|
|
size += WriteBatchInternal::ByteSize(w->batch);
|
|
if (size > max_size) {
|
|
// Do not make batch too big
|
|
break;
|
|
}
|
|
|
|
write_batch_group->push_back(w->batch);
|
|
}
|
|
*last_writer = w;
|
|
}
|
|
}
|
|
|
|
// This function computes the amount of time in microseconds by which a write
|
|
// should be delayed based on the number of level-0 files according to the
|
|
// following formula:
|
|
// if n < bottom, return 0;
|
|
// if n >= top, return 1000;
|
|
// otherwise, let r = (n - bottom) /
|
|
// (top - bottom)
|
|
// and return r^2 * 1000.
|
|
// The goal of this formula is to gradually increase the rate at which writes
|
|
// are slowed. We also tried linear delay (r * 1000), but it seemed to do
|
|
// slightly worse. There is no other particular reason for choosing quadratic.
|
|
uint64_t DBImpl::SlowdownAmount(int n, double bottom, double top) {
|
|
uint64_t delay;
|
|
if (n >= top) {
|
|
delay = 1000;
|
|
}
|
|
else if (n < bottom) {
|
|
delay = 0;
|
|
}
|
|
else {
|
|
// If we are here, we know that:
|
|
// level0_start_slowdown <= n < level0_slowdown
|
|
// since the previous two conditions are false.
|
|
double how_much =
|
|
(double) (n - bottom) /
|
|
(top - bottom);
|
|
delay = std::max(how_much * how_much * 1000, 100.0);
|
|
}
|
|
assert(delay <= 1000);
|
|
return delay;
|
|
}
|
|
|
|
// REQUIRES: mutex_ is held
|
|
// REQUIRES: this thread is currently at the front of the writer queue
|
|
Status DBImpl::MakeRoomForWrite(bool force,
|
|
SuperVersion** superversion_to_free) {
|
|
mutex_.AssertHeld();
|
|
assert(!writers_.empty());
|
|
bool allow_delay = !force;
|
|
bool allow_hard_rate_limit_delay = !force;
|
|
bool allow_soft_rate_limit_delay = !force;
|
|
uint64_t rate_limit_delay_millis = 0;
|
|
Status s;
|
|
double score;
|
|
*superversion_to_free = nullptr;
|
|
|
|
while (true) {
|
|
if (!bg_error_.ok()) {
|
|
// Yield previous error
|
|
s = bg_error_;
|
|
break;
|
|
} else if (allow_delay && versions_->NeedSlowdownForNumLevel0Files()) {
|
|
// We are getting close to hitting a hard limit on the number of
|
|
// L0 files. Rather than delaying a single write by several
|
|
// seconds when we hit the hard limit, start delaying each
|
|
// individual write by 0-1ms to reduce latency variance. Also,
|
|
// this delay hands over some CPU to the compaction thread in
|
|
// case it is sharing the same core as the writer.
|
|
uint64_t slowdown =
|
|
SlowdownAmount(versions_->current()->NumLevelFiles(0),
|
|
options_.level0_slowdown_writes_trigger,
|
|
options_.level0_stop_writes_trigger);
|
|
mutex_.Unlock();
|
|
uint64_t delayed;
|
|
{
|
|
StopWatch sw(env_, options_.statistics.get(), STALL_L0_SLOWDOWN_COUNT);
|
|
env_->SleepForMicroseconds(slowdown);
|
|
delayed = sw.ElapsedMicros();
|
|
}
|
|
RecordTick(options_.statistics.get(), STALL_L0_SLOWDOWN_MICROS, delayed);
|
|
internal_stats_.RecordWriteStall(InternalStats::LEVEL0_SLOWDOWN, delayed);
|
|
allow_delay = false; // Do not delay a single write more than once
|
|
mutex_.Lock();
|
|
delayed_writes_++;
|
|
} else if (!force && !mem_->ShouldFlush()) {
|
|
// There is room in current memtable
|
|
if (allow_delay) {
|
|
DelayLoggingAndReset();
|
|
}
|
|
break;
|
|
} else if (imm_.size() == options_.max_write_buffer_number - 1) {
|
|
// We have filled up the current memtable, but the previous
|
|
// ones are still being flushed, so we wait.
|
|
DelayLoggingAndReset();
|
|
Log(options_.info_log, "wait for memtable flush...\n");
|
|
MaybeScheduleFlushOrCompaction();
|
|
uint64_t stall;
|
|
{
|
|
StopWatch sw(env_, options_.statistics.get(),
|
|
STALL_MEMTABLE_COMPACTION_COUNT);
|
|
bg_cv_.Wait();
|
|
stall = sw.ElapsedMicros();
|
|
}
|
|
RecordTick(options_.statistics.get(),
|
|
STALL_MEMTABLE_COMPACTION_MICROS, stall);
|
|
internal_stats_.RecordWriteStall(InternalStats::MEMTABLE_COMPACTION,
|
|
stall);
|
|
} else if (versions_->current()->NumLevelFiles(0) >=
|
|
options_.level0_stop_writes_trigger) {
|
|
// There are too many level-0 files.
|
|
DelayLoggingAndReset();
|
|
Log(options_.info_log, "wait for fewer level0 files...\n");
|
|
uint64_t stall;
|
|
{
|
|
StopWatch sw(env_, options_.statistics.get(),
|
|
STALL_L0_NUM_FILES_COUNT);
|
|
bg_cv_.Wait();
|
|
stall = sw.ElapsedMicros();
|
|
}
|
|
RecordTick(options_.statistics.get(), STALL_L0_NUM_FILES_MICROS, stall);
|
|
internal_stats_.RecordWriteStall(InternalStats::LEVEL0_NUM_FILES, stall);
|
|
} else if (allow_hard_rate_limit_delay && options_.hard_rate_limit > 1.0 &&
|
|
(score = versions_->current()->MaxCompactionScore()) >
|
|
options_.hard_rate_limit) {
|
|
// Delay a write when the compaction score for any level is too large.
|
|
int max_level = versions_->current()->MaxCompactionScoreLevel();
|
|
mutex_.Unlock();
|
|
uint64_t delayed;
|
|
{
|
|
StopWatch sw(env_, options_.statistics.get(),
|
|
HARD_RATE_LIMIT_DELAY_COUNT);
|
|
env_->SleepForMicroseconds(1000);
|
|
delayed = sw.ElapsedMicros();
|
|
}
|
|
internal_stats_.RecordLevelNSlowdown(max_level, delayed);
|
|
// Make sure the following value doesn't round to zero.
|
|
uint64_t rate_limit = std::max((delayed / 1000), (uint64_t) 1);
|
|
rate_limit_delay_millis += rate_limit;
|
|
RecordTick(options_.statistics.get(),
|
|
RATE_LIMIT_DELAY_MILLIS, rate_limit);
|
|
if (options_.rate_limit_delay_max_milliseconds > 0 &&
|
|
rate_limit_delay_millis >=
|
|
(unsigned)options_.rate_limit_delay_max_milliseconds) {
|
|
allow_hard_rate_limit_delay = false;
|
|
}
|
|
mutex_.Lock();
|
|
} else if (allow_soft_rate_limit_delay && options_.soft_rate_limit > 0.0 &&
|
|
(score = versions_->current()->MaxCompactionScore()) >
|
|
options_.soft_rate_limit) {
|
|
// Delay a write when the compaction score for any level is too large.
|
|
// TODO: add statistics
|
|
mutex_.Unlock();
|
|
{
|
|
StopWatch sw(env_, options_.statistics.get(),
|
|
SOFT_RATE_LIMIT_DELAY_COUNT);
|
|
env_->SleepForMicroseconds(SlowdownAmount(
|
|
score,
|
|
options_.soft_rate_limit,
|
|
options_.hard_rate_limit)
|
|
);
|
|
rate_limit_delay_millis += sw.ElapsedMicros();
|
|
}
|
|
allow_soft_rate_limit_delay = false;
|
|
mutex_.Lock();
|
|
|
|
} else {
|
|
unique_ptr<WritableFile> lfile;
|
|
MemTable* new_mem = nullptr;
|
|
|
|
// Attempt to switch to a new memtable and trigger flush of old.
|
|
// Do this without holding the dbmutex lock.
|
|
assert(versions_->PrevLogNumber() == 0);
|
|
uint64_t new_log_number = versions_->NewFileNumber();
|
|
SuperVersion* new_superversion = nullptr;
|
|
mutex_.Unlock();
|
|
{
|
|
DelayLoggingAndReset();
|
|
s = env_->NewWritableFile(LogFileName(options_.wal_dir, new_log_number),
|
|
&lfile,
|
|
env_->OptimizeForLogWrite(storage_options_));
|
|
if (s.ok()) {
|
|
// Our final size should be less than write_buffer_size
|
|
// (compression, etc) but err on the side of caution.
|
|
lfile->SetPreallocationBlockSize(1.1 * options_.write_buffer_size);
|
|
new_mem = new MemTable(internal_comparator_, options_);
|
|
new_superversion = new SuperVersion();
|
|
}
|
|
}
|
|
mutex_.Lock();
|
|
if (!s.ok()) {
|
|
// Avoid chewing through file number space in a tight loop.
|
|
versions_->ReuseFileNumber(new_log_number);
|
|
assert (!new_mem);
|
|
break;
|
|
}
|
|
logfile_number_ = new_log_number;
|
|
log_.reset(new log::Writer(std::move(lfile)));
|
|
mem_->SetNextLogNumber(logfile_number_);
|
|
imm_.Add(mem_);
|
|
if (force) {
|
|
imm_.FlushRequested();
|
|
}
|
|
mem_ = new_mem;
|
|
mem_->Ref();
|
|
Log(options_.info_log,
|
|
"New memtable created with log file: #%lu\n",
|
|
(unsigned long)logfile_number_);
|
|
mem_->SetLogNumber(logfile_number_);
|
|
force = false; // Do not force another compaction if have room
|
|
MaybeScheduleFlushOrCompaction();
|
|
*superversion_to_free = InstallSuperVersion(new_superversion);
|
|
}
|
|
}
|
|
return s;
|
|
}
|
|
|
|
Status DBImpl::GetPropertiesOfAllTables(TablePropertiesCollection* props) {
|
|
// Increment the ref count
|
|
mutex_.Lock();
|
|
auto version = versions_->current();
|
|
version->Ref();
|
|
mutex_.Unlock();
|
|
|
|
auto s = version->GetPropertiesOfAllTables(props);
|
|
|
|
// Decrement the ref count
|
|
mutex_.Lock();
|
|
version->Unref();
|
|
mutex_.Unlock();
|
|
|
|
return s;
|
|
}
|
|
|
|
const std::string& DBImpl::GetName() const {
|
|
return dbname_;
|
|
}
|
|
|
|
Env* DBImpl::GetEnv() const {
|
|
return env_;
|
|
}
|
|
|
|
const Options& DBImpl::GetOptions() const {
|
|
return options_;
|
|
}
|
|
|
|
bool DBImpl::GetProperty(const Slice& property, std::string* value) {
|
|
value->clear();
|
|
DBPropertyType property_type = GetPropertyType(property);
|
|
MutexLock l(&mutex_);
|
|
return internal_stats_.GetProperty(property_type, property, value,
|
|
versions_.get(), imm_);
|
|
}
|
|
|
|
void DBImpl::GetApproximateSizes(
|
|
const Range* range, int n,
|
|
uint64_t* sizes) {
|
|
// TODO(opt): better implementation
|
|
Version* v;
|
|
{
|
|
MutexLock l(&mutex_);
|
|
versions_->current()->Ref();
|
|
v = versions_->current();
|
|
}
|
|
|
|
for (int i = 0; i < n; i++) {
|
|
// Convert user_key into a corresponding internal key.
|
|
InternalKey k1(range[i].start, kMaxSequenceNumber, kValueTypeForSeek);
|
|
InternalKey k2(range[i].limit, kMaxSequenceNumber, kValueTypeForSeek);
|
|
uint64_t start = versions_->ApproximateOffsetOf(v, k1);
|
|
uint64_t limit = versions_->ApproximateOffsetOf(v, k2);
|
|
sizes[i] = (limit >= start ? limit - start : 0);
|
|
}
|
|
|
|
{
|
|
MutexLock l(&mutex_);
|
|
v->Unref();
|
|
}
|
|
}
|
|
|
|
inline void DBImpl::DelayLoggingAndReset() {
|
|
if (delayed_writes_ > 0) {
|
|
Log(options_.info_log, "delayed %d write...\n", delayed_writes_ );
|
|
delayed_writes_ = 0;
|
|
}
|
|
}
|
|
|
|
Status DBImpl::DeleteFile(std::string name) {
|
|
uint64_t number;
|
|
FileType type;
|
|
WalFileType log_type;
|
|
if (!ParseFileName(name, &number, &type, &log_type) ||
|
|
(type != kTableFile && type != kLogFile)) {
|
|
Log(options_.info_log, "DeleteFile %s failed.\n", name.c_str());
|
|
return Status::InvalidArgument("Invalid file name");
|
|
}
|
|
|
|
Status status;
|
|
if (type == kLogFile) {
|
|
// Only allow deleting archived log files
|
|
if (log_type != kArchivedLogFile) {
|
|
Log(options_.info_log, "DeleteFile %s failed - not archived log.\n",
|
|
name.c_str());
|
|
return Status::NotSupported("Delete only supported for archived logs");
|
|
}
|
|
status = env_->DeleteFile(options_.wal_dir + "/" + name.c_str());
|
|
if (!status.ok()) {
|
|
Log(options_.info_log, "DeleteFile %s failed -- %s.\n",
|
|
name.c_str(), status.ToString().c_str());
|
|
}
|
|
return status;
|
|
}
|
|
|
|
int level;
|
|
FileMetaData* metadata;
|
|
int maxlevel = NumberLevels();
|
|
VersionEdit edit;
|
|
DeletionState deletion_state(true);
|
|
{
|
|
MutexLock l(&mutex_);
|
|
status = versions_->GetMetadataForFile(number, &level, &metadata);
|
|
if (!status.ok()) {
|
|
Log(options_.info_log, "DeleteFile %s failed. File not found\n",
|
|
name.c_str());
|
|
return Status::InvalidArgument("File not found");
|
|
}
|
|
assert((level > 0) && (level < maxlevel));
|
|
|
|
// If the file is being compacted no need to delete.
|
|
if (metadata->being_compacted) {
|
|
Log(options_.info_log,
|
|
"DeleteFile %s Skipped. File about to be compacted\n", name.c_str());
|
|
return Status::OK();
|
|
}
|
|
|
|
// Only the files in the last level can be deleted externally.
|
|
// This is to make sure that any deletion tombstones are not
|
|
// lost. Check that the level passed is the last level.
|
|
for (int i = level + 1; i < maxlevel; i++) {
|
|
if (versions_->current()->NumLevelFiles(i) != 0) {
|
|
Log(options_.info_log,
|
|
"DeleteFile %s FAILED. File not in last level\n", name.c_str());
|
|
return Status::InvalidArgument("File not in last level");
|
|
}
|
|
}
|
|
edit.DeleteFile(level, number);
|
|
status = versions_->LogAndApply(&edit, &mutex_, db_directory_.get());
|
|
if (status.ok()) {
|
|
InstallSuperVersion(deletion_state);
|
|
}
|
|
FindObsoleteFiles(deletion_state, false);
|
|
} // lock released here
|
|
LogFlush(options_.info_log);
|
|
// remove files outside the db-lock
|
|
if (deletion_state.HaveSomethingToDelete()) {
|
|
PurgeObsoleteFiles(deletion_state);
|
|
}
|
|
{
|
|
MutexLock l(&mutex_);
|
|
// schedule flush if file deletion means we freed the space for flushes to
|
|
// continue
|
|
MaybeScheduleFlushOrCompaction();
|
|
}
|
|
return status;
|
|
}
|
|
|
|
void DBImpl::GetLiveFilesMetaData(std::vector<LiveFileMetaData> *metadata) {
|
|
MutexLock l(&mutex_);
|
|
return versions_->GetLiveFilesMetaData(metadata);
|
|
}
|
|
|
|
void DBImpl::TEST_GetFilesMetaData(
|
|
std::vector<std::vector<FileMetaData>>* metadata) {
|
|
MutexLock l(&mutex_);
|
|
metadata->resize(NumberLevels());
|
|
for (int level = 0; level < NumberLevels(); level++) {
|
|
const std::vector<FileMetaData*>& files =
|
|
versions_->current()->files_[level];
|
|
|
|
(*metadata)[level].clear();
|
|
for (const auto& f : files) {
|
|
(*metadata)[level].push_back(*f);
|
|
}
|
|
}
|
|
}
|
|
|
|
Status DBImpl::GetDbIdentity(std::string& identity) {
|
|
std::string idfilename = IdentityFileName(dbname_);
|
|
unique_ptr<SequentialFile> idfile;
|
|
const EnvOptions soptions;
|
|
Status s = env_->NewSequentialFile(idfilename, &idfile, soptions);
|
|
if (!s.ok()) {
|
|
return s;
|
|
}
|
|
uint64_t file_size;
|
|
s = env_->GetFileSize(idfilename, &file_size);
|
|
if (!s.ok()) {
|
|
return s;
|
|
}
|
|
char buffer[file_size];
|
|
Slice id;
|
|
s = idfile->Read(file_size, &id, buffer);
|
|
if (!s.ok()) {
|
|
return s;
|
|
}
|
|
identity.assign(id.ToString());
|
|
// If last character is '\n' remove it from identity
|
|
if (identity.size() > 0 && identity.back() == '\n') {
|
|
identity.pop_back();
|
|
}
|
|
return s;
|
|
}
|
|
|
|
// Default implementations of convenience methods that subclasses of DB
|
|
// can call if they wish
|
|
Status DB::Put(const WriteOptions& opt, const Slice& key, const Slice& value) {
|
|
// Pre-allocate size of write batch conservatively.
|
|
// 8 bytes are taken by header, 4 bytes for count, 1 byte for type,
|
|
// and we allocate 11 extra bytes for key length, as well as value length.
|
|
WriteBatch batch(key.size() + value.size() + 24);
|
|
batch.Put(key, value);
|
|
return Write(opt, &batch);
|
|
}
|
|
|
|
Status DB::Delete(const WriteOptions& opt, const Slice& key) {
|
|
WriteBatch batch;
|
|
batch.Delete(key);
|
|
return Write(opt, &batch);
|
|
}
|
|
|
|
Status DB::Merge(const WriteOptions& opt, const Slice& key,
|
|
const Slice& value) {
|
|
WriteBatch batch;
|
|
batch.Merge(key, value);
|
|
return Write(opt, &batch);
|
|
}
|
|
|
|
DB::~DB() { }
|
|
|
|
Status DB::Open(const Options& options, const std::string& dbname, DB** dbptr) {
|
|
*dbptr = nullptr;
|
|
|
|
if (options.block_cache != nullptr && options.no_block_cache) {
|
|
return Status::InvalidArgument(
|
|
"no_block_cache is true while block_cache is not nullptr");
|
|
}
|
|
|
|
DBImpl* impl = new DBImpl(options, dbname);
|
|
Status s = impl->env_->CreateDirIfMissing(impl->options_.wal_dir);
|
|
if (!s.ok()) {
|
|
delete impl;
|
|
return s;
|
|
}
|
|
|
|
s = impl->CreateArchivalDirectory();
|
|
if (!s.ok()) {
|
|
delete impl;
|
|
return s;
|
|
}
|
|
impl->mutex_.Lock();
|
|
s = impl->Recover(); // Handles create_if_missing, error_if_exists
|
|
if (s.ok()) {
|
|
uint64_t new_log_number = impl->versions_->NewFileNumber();
|
|
unique_ptr<WritableFile> lfile;
|
|
EnvOptions soptions(options);
|
|
s = impl->options_.env->NewWritableFile(
|
|
LogFileName(impl->options_.wal_dir, new_log_number), &lfile,
|
|
impl->options_.env->OptimizeForLogWrite(soptions));
|
|
if (s.ok()) {
|
|
lfile->SetPreallocationBlockSize(1.1 * impl->options_.write_buffer_size);
|
|
VersionEdit edit;
|
|
edit.SetLogNumber(new_log_number);
|
|
impl->logfile_number_ = new_log_number;
|
|
impl->log_.reset(new log::Writer(std::move(lfile)));
|
|
s = impl->versions_->LogAndApply(&edit, &impl->mutex_,
|
|
impl->db_directory_.get());
|
|
}
|
|
if (s.ok()) {
|
|
delete impl->InstallSuperVersion(new DBImpl::SuperVersion());
|
|
impl->mem_->SetLogNumber(impl->logfile_number_);
|
|
impl->DeleteObsoleteFiles();
|
|
impl->MaybeScheduleFlushOrCompaction();
|
|
impl->MaybeScheduleLogDBDeployStats();
|
|
s = impl->db_directory_->Fsync();
|
|
}
|
|
}
|
|
|
|
if (s.ok() && impl->options_.compaction_style == kCompactionStyleUniversal) {
|
|
Version* current = impl->versions_->current();
|
|
for (int i = 1; i < impl->NumberLevels(); i++) {
|
|
int num_files = current->NumLevelFiles(i);
|
|
if (num_files > 0) {
|
|
s = Status::InvalidArgument("Not all files are at level 0. Cannot "
|
|
"open with universal compaction style.");
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
impl->mutex_.Unlock();
|
|
|
|
if (s.ok()) {
|
|
impl->opened_successfully_ = true;
|
|
*dbptr = impl;
|
|
} else {
|
|
delete impl;
|
|
}
|
|
return s;
|
|
}
|
|
|
|
Snapshot::~Snapshot() {
|
|
}
|
|
|
|
Status DestroyDB(const std::string& dbname, const Options& options) {
|
|
const InternalKeyComparator comparator(options.comparator);
|
|
const InternalFilterPolicy filter_policy(options.filter_policy);
|
|
const Options& soptions(SanitizeOptions(
|
|
dbname, &comparator, &filter_policy, options));
|
|
Env* env = soptions.env;
|
|
std::vector<std::string> filenames;
|
|
std::vector<std::string> archiveFiles;
|
|
|
|
std::string archivedir = ArchivalDirectory(dbname);
|
|
// Ignore error in case directory does not exist
|
|
env->GetChildren(dbname, &filenames);
|
|
|
|
if (dbname != soptions.wal_dir) {
|
|
std::vector<std::string> logfilenames;
|
|
env->GetChildren(soptions.wal_dir, &logfilenames);
|
|
filenames.insert(filenames.end(), logfilenames.begin(), logfilenames.end());
|
|
archivedir = ArchivalDirectory(soptions.wal_dir);
|
|
}
|
|
|
|
if (filenames.empty()) {
|
|
return Status::OK();
|
|
}
|
|
|
|
FileLock* lock;
|
|
const std::string lockname = LockFileName(dbname);
|
|
Status result = env->LockFile(lockname, &lock);
|
|
if (result.ok()) {
|
|
uint64_t number;
|
|
FileType type;
|
|
for (size_t i = 0; i < filenames.size(); i++) {
|
|
if (ParseFileName(filenames[i], &number, &type) &&
|
|
type != kDBLockFile) { // Lock file will be deleted at end
|
|
Status del;
|
|
if (type == kMetaDatabase) {
|
|
del = DestroyDB(dbname + "/" + filenames[i], options);
|
|
} else if (type == kLogFile) {
|
|
del = env->DeleteFile(soptions.wal_dir + "/" + filenames[i]);
|
|
} else {
|
|
del = env->DeleteFile(dbname + "/" + filenames[i]);
|
|
}
|
|
if (result.ok() && !del.ok()) {
|
|
result = del;
|
|
}
|
|
}
|
|
}
|
|
|
|
env->GetChildren(archivedir, &archiveFiles);
|
|
// Delete archival files.
|
|
for (size_t i = 0; i < archiveFiles.size(); ++i) {
|
|
if (ParseFileName(archiveFiles[i], &number, &type) &&
|
|
type == kLogFile) {
|
|
Status del = env->DeleteFile(archivedir + "/" + archiveFiles[i]);
|
|
if (result.ok() && !del.ok()) {
|
|
result = del;
|
|
}
|
|
}
|
|
}
|
|
// ignore case where no archival directory is present.
|
|
env->DeleteDir(archivedir);
|
|
|
|
env->UnlockFile(lock); // Ignore error since state is already gone
|
|
env->DeleteFile(lockname);
|
|
env->DeleteDir(dbname); // Ignore error in case dir contains other files
|
|
env->DeleteDir(soptions.wal_dir);
|
|
}
|
|
return result;
|
|
}
|
|
|
|
//
|
|
// A global method that can dump out the build version
|
|
void DumpLeveldbBuildVersion(Logger * log) {
|
|
Log(log, "Git sha %s", rocksdb_build_git_sha);
|
|
Log(log, "Compile time %s %s",
|
|
rocksdb_build_compile_time, rocksdb_build_compile_date);
|
|
}
|
|
|
|
} // namespace rocksdb
|