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Support for single-primary, multi-secondary instances (#4899) 

Summary:
This PR allows RocksDB to run in single-primary, multi-secondary process mode.
The writer is a regular RocksDB (e.g. an `DBImpl`) instance playing the role of a primary.
Multiple `DBImplSecondary` processes (secondaries) share the same set of SST files, MANIFEST, WAL files with the primary. Secondaries tail the MANIFEST of the primary and apply updates to their own in-memory state of the file system, e.g. `VersionStorageInfo`.

This PR has several components:
1. (Originally in #4745). Add a `PathNotFound` subcode to `IOError` to denote the failure when a secondary tries to open a file which has been deleted by the primary.

2. (Similar to #4602). Add `FragmentBufferedReader` to handle partially-read, trailing record at the end of a log from where future read can continue.

3. (Originally in #4710 and #4820). Add implementation of the secondary, i.e. `DBImplSecondary`.
3.1 Tail the primary's MANIFEST during recovery.
3.2 Tail the primary's MANIFEST during normal processing by calling `ReadAndApply`.
3.3 Tailing WAL will be in a future PR.

4. Add an example in 'examples/multi_processes_example.cc' to demonstrate the usage of secondary RocksDB instance in a multi-process setting. Instructions to run the example can be found at the beginning of the source code.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4899

Differential Revision: D14510945

Pulled By: riversand963

fbshipit-source-id: 4ac1c5693e6012ad23f7b4b42d3c374fecbe8886
This commit is contained in:
Yanqin Jin 2019-03-26 16:41:31 -07:00 committed by Facebook Github Bot
parent 2a5463ae84
commit 9358178edc
32 changed files with 2597 additions and 283 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
CMakeLists.txt
View File

@ -489,6 +489,7 @@ set(SOURCES
db/db_impl_debug.cc
db/db_impl_experimental.cc
db/db_impl_readonly.cc
db/db_impl_secondary.cc
db/db_info_dumper.cc
db/db_iter.cc
db/dbformat.cc
@ -873,6 +874,7 @@ if(WITH_TESTS)
db/db_options_test.cc
db/db_properties_test.cc
db/db_range_del_test.cc
db/db_secondary_test.cc
db/db_sst_test.cc
db/db_statistics_test.cc
db/db_table_properties_test.cc

13
HISTORY.md
View File

@ -2,24 +2,17 @@
## Unreleased
### New Features
* Introduce two more stats levels, kExceptHistogramOrTimers and kExceptTimers.
* Added a feature to perform data-block sampling for compressibility, and report stats to user.
* Add support for trace filtering.
### Public API Change
* Remove bundled fbson library.
* statistics.stats_level_ becomes atomic. It is preferred to use statistics.set_stats_level() and statistics.get_stats_level() to access it.
* Introduce a new IOError subcode, PathNotFound, to indicate trying to open a nonexistent file or directory for read.
* Add initial support for multiple db instances sharing the same data in single-writer, multi-reader mode.
### Bug Fixes
* Fix JEMALLOC_CXX_THROW macro missing from older Jemalloc versions, causing build failures on some platforms.
* Fix SstFileReader not able to open file ingested with write_glbal_seqno=true.
## Unreleased
### New Features
* Added a feature to perform data-block sampling for compressibility, and report stats to user.
### Public API Change
### Bug fixes
## 6.0.0 (2/19/2019)
### New Features
* Enabled checkpoint on readonly db (DBImplReadOnly).

5
Makefile
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@ -443,6 +443,7 @@ TESTS = \
db_merge_operator_test \
db_options_test \
db_range_del_test \
db_secondary_test \
db_sst_test \
db_tailing_iter_test \
db_io_failure_test \
@ -547,6 +548,7 @@ TESTS = \
range_tombstone_fragmenter_test \
range_del_aggregator_test \
sst_file_reader_test \
db_secondary_test \
PARALLEL_TEST = \
backupable_db_test \
@ -1571,6 +1573,9 @@ range_tombstone_fragmenter_test: db/range_tombstone_fragmenter_test.o db/db_test
sst_file_reader_test: table/sst_file_reader_test.o $(LIBOBJECTS) $(TESTHARNESS)
$(AM_LINK)
db_secondary_test: db/db_secondary_test.o db/db_test_util.o $(LIBOBJECTS) $(TESTHARNESS)
$(AM_LINK)
#-------------------------------------------------
# make install related stuff
INSTALL_PATH ?= /usr/local

6
TARGETS
View File

@ -98,6 +98,7 @@ cpp_library(
"db/db_impl_files.cc",
"db/db_impl_open.cc",
"db/db_impl_readonly.cc",
"db/db_impl_secondary.cc",
"db/db_impl_write.cc",
"db/db_info_dumper.cc",
"db/db_iter.cc",
@ -605,6 +606,11 @@ ROCKS_TESTS = [
"db/db_range_del_test.cc",
"serial",
],
[
"db_secondary_test",
"db/db_secondary_test.cc",
"serial",
],
[
"db_sst_test",
"db/db_sst_test.cc",

12
db/db_impl.cc
View File

@ -148,18 +148,21 @@ DBImpl::DBImpl(const DBOptions& options, const std::string& dbname,
immutable_db_options_(initial_db_options_),
mutable_db_options_(initial_db_options_),
stats_(immutable_db_options_.statistics.get()),
db_lock_(nullptr),
mutex_(stats_, env_, DB_MUTEX_WAIT_MICROS,
immutable_db_options_.use_adaptive_mutex),
default_cf_handle_(nullptr),
max_total_in_memory_state_(0),
env_options_(BuildDBOptions(immutable_db_options_, mutable_db_options_)),
env_options_for_compaction_(env_->OptimizeForCompactionTableWrite(
env_options_, immutable_db_options_)),
db_lock_(nullptr),
shutting_down_(false),
bg_cv_(&mutex_),
logfile_number_(0),
log_dir_synced_(false),
log_empty_(true),
default_cf_handle_(nullptr),
log_sync_cv_(&mutex_),
total_log_size_(0),
max_total_in_memory_state_(0),
is_snapshot_supported_(true),
write_buffer_manager_(immutable_db_options_.write_buffer_manager.get()),
write_thread_(immutable_db_options_),
@ -186,9 +189,6 @@ DBImpl::DBImpl(const DBOptions& options, const std::string& dbname,
next_job_id_(1),
has_unpersisted_data_(false),
unable_to_release_oldest_log_(false),
env_options_(BuildDBOptions(immutable_db_options_, mutable_db_options_)),
env_options_for_compaction_(env_->OptimizeForCompactionTableWrite(
env_options_, immutable_db_options_)),
num_running_ingest_file_(0),
#ifndef ROCKSDB_LITE
wal_manager_(immutable_db_options_, env_options_, seq_per_batch),

60
db/db_impl.h
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@ -758,6 +758,29 @@ class DBImpl : public DB {
std::unique_ptr<Tracer> tracer_;
InstrumentedMutex trace_mutex_;
// State below is protected by mutex_
// With two_write_queues enabled, some of the variables that accessed during
// WriteToWAL need different synchronization: log_empty_, alive_log_files_,
// logs_, logfile_number_. Refer to the definition of each variable below for
// more description.
mutable InstrumentedMutex mutex_;
ColumnFamilyHandleImpl* default_cf_handle_;
InternalStats* default_cf_internal_stats_;
// only used for dynamically adjusting max_total_wal_size. it is a sum of
// [write_buffer_size * max_write_buffer_number] over all column families
uint64_t max_total_in_memory_state_;
// If true, we have only one (default) column family. We use this to optimize
// some code-paths
bool single_column_family_mode_;
// The options to access storage files
const EnvOptions env_options_;
// Additonal options for compaction and flush
EnvOptions env_options_for_compaction_;
// Except in DB::Open(), WriteOptionsFile can only be called when:
// Persist options to options file.
// If need_mutex_lock = false, the method will lock DB mutex.
@ -845,6 +868,14 @@ class DBImpl : public DB {
// Actual implementation of Close()
Status CloseImpl();
// Recover the descriptor from persistent storage. May do a significant
// amount of work to recover recently logged updates. Any changes to
// be made to the descriptor are added to *edit.
virtual Status Recover(
const std::vector<ColumnFamilyDescriptor>& column_families,
bool read_only = false, bool error_if_log_file_exist = false,
bool error_if_data_exists_in_logs = false);
private:
friend class DB;
friend class ErrorHandler;
@ -893,13 +924,6 @@ class DBImpl : public DB {
struct PrepickedCompaction;
struct PurgeFileInfo;
// Recover the descriptor from persistent storage. May do a significant
// amount of work to recover recently logged updates. Any changes to
// be made to the descriptor are added to *edit.
Status Recover(const std::vector<ColumnFamilyDescriptor>& column_families,
bool read_only = false, bool error_if_log_file_exist = false,
bool error_if_data_exists_in_logs = false);
Status ResumeImpl();
void MaybeIgnoreError(Status* s) const;
@ -1216,12 +1240,6 @@ class DBImpl : public DB {
// and log_empty_. Refer to the definition of each variable below for more
// details.
InstrumentedMutex log_write_mutex_;
// State below is protected by mutex_
// With two_write_queues enabled, some of the variables that accessed during
// WriteToWAL need different synchronization: log_empty_, alive_log_files_,
// logs_, logfile_number_. Refer to the definition of each variable below for
// more description.
mutable InstrumentedMutex mutex_;
std::atomic<bool> shutting_down_;
// This condition variable is signaled on these conditions:
@ -1253,8 +1271,7 @@ class DBImpl : public DB {
// read and writes are protected by log_write_mutex_ instead. This is to avoid
// expesnive mutex_ lock during WAL write, which update log_empty_.
bool log_empty_;
ColumnFamilyHandleImpl* default_cf_handle_;
InternalStats* default_cf_internal_stats_;
std::unique_ptr<ColumnFamilyMemTablesImpl> column_family_memtables_;
struct LogFileNumberSize {
explicit LogFileNumberSize(uint64_t _number)
@ -1321,12 +1338,7 @@ class DBImpl : public DB {
WriteBatch cached_recoverable_state_;
std::atomic<bool> cached_recoverable_state_empty_ = {true};
std::atomic<uint64_t> total_log_size_;
// only used for dynamically adjusting max_total_wal_size. it is a sum of
// [write_buffer_size * max_write_buffer_number] over all column families
uint64_t max_total_in_memory_state_;
// If true, we have only one (default) column family. We use this to optimize
// some code-paths
bool single_column_family_mode_;
// If this is non-empty, we need to delete these log files in background
// threads. Protected by db mutex.
autovector<log::Writer*> logs_to_free_;
@ -1545,12 +1557,6 @@ class DBImpl : public DB {
std::string db_absolute_path_;
// The options to access storage files
const EnvOptions env_options_;
// Additonal options for compaction and flush
EnvOptions env_options_for_compaction_;
// Number of running IngestExternalFile() calls.
// REQUIRES: mutex held
int num_running_ingest_file_;

3
db/db_impl_open.cc
View File

@ -629,8 +629,7 @@ Status DBImpl::RecoverLogFiles(const std::vector<uint64_t>& log_numbers,
// to be skipped instead of propagating bad information (like overly
// large sequence numbers).
log::Reader reader(immutable_db_options_.info_log, std::move(file_reader),
&reporter, true /*checksum*/, log_number,
false /* retry_after_eof */);
&reporter, true /*checksum*/, log_number);
// Determine if we should tolerate incomplete records at the tail end of the
// Read all the records and add to a memtable

356
db/db_impl_secondary.cc Normal file
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@ -0,0 +1,356 @@
// Copyright (c) 2011-present, Facebook, Inc. All rights reserved.
// This source code is licensed under both the GPLv2 (found in the
// COPYING file in the root directory) and Apache 2.0 License
// (found in the LICENSE.Apache file in the root directory).
#include "db/db_impl_secondary.h"
#include "db/db_iter.h"
#include "db/merge_context.h"
#include "monitoring/perf_context_imp.h"
#include "util/auto_roll_logger.h"
namespace rocksdb {
#ifndef ROCKSDB_LITE
DBImplSecondary::DBImplSecondary(const DBOptions& db_options,
const std::string& dbname)
: DBImpl(db_options, dbname) {
ROCKS_LOG_INFO(immutable_db_options_.info_log,
"Opening the db in secondary mode");
LogFlush(immutable_db_options_.info_log);
}
DBImplSecondary::~DBImplSecondary() {}
Status DBImplSecondary::Recover(
const std::vector<ColumnFamilyDescriptor>& column_families,
bool /*readonly*/, bool /*error_if_log_file_exist*/,
bool /*error_if_data_exists_in_logs*/) {
mutex_.AssertHeld();
Status s;
s = static_cast<ReactiveVersionSet*>(versions_.get())
->Recover(column_families, &manifest_reader_, &manifest_reporter_,
&manifest_reader_status_);
if (!s.ok()) {
return s;
}
if (immutable_db_options_.paranoid_checks && s.ok()) {
s = CheckConsistency();
}
// Initial max_total_in_memory_state_ before recovery logs.
max_total_in_memory_state_ = 0;
for (auto cfd : *versions_->GetColumnFamilySet()) {
auto* mutable_cf_options = cfd->GetLatestMutableCFOptions();
max_total_in_memory_state_ += mutable_cf_options->write_buffer_size *
mutable_cf_options->max_write_buffer_number;
}
if (s.ok()) {
default_cf_handle_ = new ColumnFamilyHandleImpl(
versions_->GetColumnFamilySet()->GetDefault(), this, &mutex_);
default_cf_internal_stats_ = default_cf_handle_->cfd()->internal_stats();
single_column_family_mode_ =
versions_->GetColumnFamilySet()->NumberOfColumnFamilies() == 1;
}
// TODO: attempt to recover from WAL files.
return s;
}
// Implementation of the DB interface
Status DBImplSecondary::Get(const ReadOptions& read_options,
ColumnFamilyHandle* column_family, const Slice& key,
PinnableSlice* value) {
return GetImpl(read_options, column_family, key, value);
}
Status DBImplSecondary::GetImpl(const ReadOptions& read_options,
ColumnFamilyHandle* column_family,
const Slice& key, PinnableSlice* pinnable_val) {
assert(pinnable_val != nullptr);
PERF_CPU_TIMER_GUARD(get_cpu_nanos, env_);
StopWatch sw(env_, stats_, DB_GET);
PERF_TIMER_GUARD(get_snapshot_time);
auto cfh = static_cast<ColumnFamilyHandleImpl*>(column_family);
ColumnFamilyData* cfd = cfh->cfd();
if (tracer_) {
InstrumentedMutexLock lock(&trace_mutex_);
if (tracer_) {
tracer_->Get(column_family, key);
}
}
// Acquire SuperVersion
SuperVersion* super_version = GetAndRefSuperVersion(cfd);
SequenceNumber snapshot = versions_->LastSequence();
MergeContext merge_context;
SequenceNumber max_covering_tombstone_seq = 0;
Status s;
LookupKey lkey(key, snapshot);
PERF_TIMER_STOP(get_snapshot_time);
bool done = false;
if (super_version->mem->Get(lkey, pinnable_val->GetSelf(), &s, &merge_context,
&max_covering_tombstone_seq, read_options)) {
done = true;
pinnable_val->PinSelf();
RecordTick(stats_, MEMTABLE_HIT);
} else if ((s.ok() || s.IsMergeInProgress()) &&
super_version->imm->Get(
lkey, pinnable_val->GetSelf(), &s, &merge_context,
&max_covering_tombstone_seq, read_options)) {
done = true;
pinnable_val->PinSelf();
RecordTick(stats_, MEMTABLE_HIT);
}
if (!done && !s.ok() && !s.IsMergeInProgress()) {
ReturnAndCleanupSuperVersion(cfd, super_version);
return s;
}
if (!done) {
PERF_TIMER_GUARD(get_from_output_files_time);
super_version->current->Get(read_options, lkey, pinnable_val, &s,
&merge_context, &max_covering_tombstone_seq);
RecordTick(stats_, MEMTABLE_MISS);
}
{
PERF_TIMER_GUARD(get_post_process_time);
ReturnAndCleanupSuperVersion(cfd, super_version);
RecordTick(stats_, NUMBER_KEYS_READ);
size_t size = pinnable_val->size();
RecordTick(stats_, BYTES_READ, size);
RecordTimeToHistogram(stats_, BYTES_PER_READ, size);
PERF_COUNTER_ADD(get_read_bytes, size);
}
return s;
}
Iterator* DBImplSecondary::NewIterator(const ReadOptions& read_options,
ColumnFamilyHandle* column_family) {
if (read_options.managed) {
return NewErrorIterator(
Status::NotSupported("Managed iterator is not supported anymore."));
}
if (read_options.read_tier == kPersistedTier) {
return NewErrorIterator(Status::NotSupported(
"ReadTier::kPersistedData is not yet supported in iterators."));
}
Iterator* result = nullptr;
auto cfh = reinterpret_cast<ColumnFamilyHandleImpl*>(column_family);
auto cfd = cfh->cfd();
ReadCallback* read_callback = nullptr; // No read callback provided.
if (read_options.tailing) {
return NewErrorIterator(Status::NotSupported(
"tailing iterator not supported in secondary mode"));
} else if (read_options.snapshot != nullptr) {
// TODO (yanqin) support snapshot.
return NewErrorIterator(
Status::NotSupported("snapshot not supported in secondary mode"));
} else {
auto snapshot = versions_->LastSequence();
result = NewIteratorImpl(read_options, cfd, snapshot, read_callback);
}
return result;
}
ArenaWrappedDBIter* DBImplSecondary::NewIteratorImpl(
const ReadOptions& read_options, ColumnFamilyData* cfd,
SequenceNumber snapshot, ReadCallback* read_callback) {
assert(nullptr != cfd);
SuperVersion* super_version = cfd->GetReferencedSuperVersion(&mutex_);
auto db_iter = NewArenaWrappedDbIterator(
env_, read_options, *cfd->ioptions(), super_version->mutable_cf_options,
snapshot,
super_version->mutable_cf_options.max_sequential_skip_in_iterations,
super_version->version_number, read_callback);
auto internal_iter =
NewInternalIterator(read_options, cfd, super_version, db_iter->GetArena(),
db_iter->GetRangeDelAggregator(), snapshot);
db_iter->SetIterUnderDBIter(internal_iter);
return db_iter;
}
Status DBImplSecondary::NewIterators(
const ReadOptions& read_options,
const std::vector<ColumnFamilyHandle*>& column_families,
std::vector<Iterator*>* iterators) {
if (read_options.managed) {
return Status::NotSupported("Managed iterator is not supported anymore.");
}
if (read_options.read_tier == kPersistedTier) {
return Status::NotSupported(
"ReadTier::kPersistedData is not yet supported in iterators.");
}
ReadCallback* read_callback = nullptr; // No read callback provided.
if (iterators == nullptr) {
return Status::InvalidArgument("iterators not allowed to be nullptr");
}
iterators->clear();
iterators->reserve(column_families.size());
if (read_options.tailing) {
return Status::NotSupported(
"tailing iterator not supported in secondary mode");
} else if (read_options.snapshot != nullptr) {
// TODO (yanqin) support snapshot.
return Status::NotSupported("snapshot not supported in secondary mode");
} else {
SequenceNumber read_seq = versions_->LastSequence();
for (auto cfh : column_families) {
ColumnFamilyData* cfd = static_cast<ColumnFamilyHandleImpl*>(cfh)->cfd();
iterators->push_back(
NewIteratorImpl(read_options, cfd, read_seq, read_callback));
}
}
return Status::OK();
}
Status DBImplSecondary::TryCatchUpWithPrimary() {
assert(versions_.get() != nullptr);
assert(manifest_reader_.get() != nullptr);
Status s;
std::unordered_set<ColumnFamilyData*> cfds_changed;
InstrumentedMutexLock lock_guard(&mutex_);
s = static_cast<ReactiveVersionSet*>(versions_.get())
->ReadAndApply(&mutex_, &manifest_reader_, &cfds_changed);
if (s.ok()) {
SuperVersionContext sv_context(true /* create_superversion */);
for (auto cfd : cfds_changed) {
sv_context.NewSuperVersion();
cfd->InstallSuperVersion(&sv_context, &mutex_);
}
sv_context.Clean();
}
return s;
}
Status DB::OpenAsSecondary(const Options& options, const std::string& dbname,
const std::string& secondary_path, DB** dbptr) {
*dbptr = nullptr;
DBOptions db_options(options);
ColumnFamilyOptions cf_options(options);
std::vector<ColumnFamilyDescriptor> column_families;
column_families.emplace_back(kDefaultColumnFamilyName, cf_options);
std::vector<ColumnFamilyHandle*> handles;
Status s = DB::OpenAsSecondary(db_options, dbname, secondary_path,
column_families, &handles, dbptr);
if (s.ok()) {
assert(handles.size() == 1);
delete handles[0];
}
return s;
}
Status DB::OpenAsSecondary(
const DBOptions& db_options, const std::string& dbname,
const std::string& secondary_path,
const std::vector<ColumnFamilyDescriptor>& column_families,
std::vector<ColumnFamilyHandle*>* handles, DB** dbptr) {
*dbptr = nullptr;
if (db_options.max_open_files != -1) {
// TODO (yanqin) maybe support max_open_files != -1 by creating hard links
// on SST files so that db secondary can still have access to old SSTs
// while primary instance may delete original.
return Status::InvalidArgument("require max_open_files to be -1");
}
DBOptions tmp_opts(db_options);
if (nullptr == tmp_opts.info_log) {
Env* env = tmp_opts.env;
assert(env != nullptr);
std::string secondary_abs_path;
env->GetAbsolutePath(secondary_path, &secondary_abs_path);
std::string fname = InfoLogFileName(secondary_path, secondary_abs_path,
tmp_opts.db_log_dir);
env->CreateDirIfMissing(secondary_path);
if (tmp_opts.log_file_time_to_roll > 0 || tmp_opts.max_log_file_size > 0) {
AutoRollLogger* result = new AutoRollLogger(
env, secondary_path, tmp_opts.db_log_dir, tmp_opts.max_log_file_size,
tmp_opts.log_file_time_to_roll, tmp_opts.info_log_level);
Status s = result->GetStatus();
if (!s.ok()) {
delete result;
} else {
tmp_opts.info_log.reset(result);
}
}
if (nullptr == tmp_opts.info_log) {
env->RenameFile(
fname, OldInfoLogFileName(secondary_path, env->NowMicros(),
secondary_abs_path, tmp_opts.db_log_dir));
Status s = env->NewLogger(fname, &(tmp_opts.info_log));
if (tmp_opts.info_log != nullptr) {
tmp_opts.info_log->SetInfoLogLevel(tmp_opts.info_log_level);
}
}
}
assert(tmp_opts.info_log != nullptr);
handles->clear();
DBImplSecondary* impl = new DBImplSecondary(tmp_opts, dbname);
impl->versions_.reset(new ReactiveVersionSet(
dbname, &impl->immutable_db_options_, impl->env_options_,
impl->table_cache_.get(), impl->write_buffer_manager_,
&impl->write_controller_));
impl->column_family_memtables_.reset(
new ColumnFamilyMemTablesImpl(impl->versions_->GetColumnFamilySet()));
impl->mutex_.Lock();
Status s = impl->Recover(column_families, true, false, false);
if (s.ok()) {
for (auto cf : column_families) {
auto cfd =
impl->versions_->GetColumnFamilySet()->GetColumnFamily(cf.name);
if (nullptr == cfd) {
s = Status::InvalidArgument("Column family not found: ", cf.name);
break;
}
handles->push_back(new ColumnFamilyHandleImpl(cfd, impl, &impl->mutex_));
}
}
SuperVersionContext sv_context(true /* create_superversion */);
if (s.ok()) {
for (auto cfd : *impl->versions_->GetColumnFamilySet()) {
sv_context.NewSuperVersion();
cfd->InstallSuperVersion(&sv_context, &impl->mutex_);
}
}
impl->mutex_.Unlock();
sv_context.Clean();
if (s.ok()) {
*dbptr = impl;
for (auto h : *handles) {
impl->NewThreadStatusCfInfo(
reinterpret_cast<ColumnFamilyHandleImpl*>(h)->cfd());
}
} else {
for (auto h : *handles) {
delete h;
}
handles->clear();
delete impl;
}
return s;
}
#else // !ROCKSDB_LITE
Status DB::OpenAsSecondary(const Options& /*options*/,
const std::string& /*name*/,
const std::string& /*secondary_path*/,
DB** /*dbptr*/) {
return Status::NotSupported("Not supported in ROCKSDB_LITE.");
}
Status DB::OpenAsSecondary(
const DBOptions& /*db_options*/, const std::string& /*dbname*/,
const std::string& /*secondary_path*/,
const std::vector<ColumnFamilyDescriptor>& /*column_families*/,
std::vector<ColumnFamilyHandle*>* /*handles*/, DB** /*dbptr*/) {
return Status::NotSupported("Not supported in ROCKSDB_LITE.");
}
#endif // !ROCKSDB_LITE
} // namespace rocksdb

151
db/db_impl_secondary.h Normal file
View File

@ -0,0 +1,151 @@
// Copyright (c) 2011-present, Facebook, Inc. All rights reserved.
// This source code is licensed under both the GPLv2 (found in the
// COPYING file in the root directory) and Apache 2.0 License
// (found in the LICENSE.Apache file in the root directory).
#pragma once
#ifndef ROCKSDB_LITE
#include <string>
#include <vector>
#include "db/db_impl.h"
namespace rocksdb {
class DBImplSecondary : public DBImpl {
public:
DBImplSecondary(const DBOptions& options, const std::string& dbname);
~DBImplSecondary() override;
Status Recover(const std::vector<ColumnFamilyDescriptor>& column_families,
bool read_only, bool error_if_log_file_exist,
bool error_if_data_exists_in_logs) override;
// Implementations of the DB interface
using DB::Get;
Status Get(const ReadOptions& options, ColumnFamilyHandle* column_family,
const Slice& key, PinnableSlice* value) override;
Status GetImpl(const ReadOptions& options, ColumnFamilyHandle* column_family,
const Slice& key, PinnableSlice* value);
using DBImpl::NewIterator;
Iterator* NewIterator(const ReadOptions&,
ColumnFamilyHandle* column_family) override;
ArenaWrappedDBIter* NewIteratorImpl(const ReadOptions& read_options,
ColumnFamilyData* cfd,
SequenceNumber snapshot,
ReadCallback* read_callback);
Status NewIterators(const ReadOptions& options,
const std::vector<ColumnFamilyHandle*>& column_families,
std::vector<Iterator*>* iterators) override;
using DBImpl::Put;
Status Put(const WriteOptions& /*options*/,
ColumnFamilyHandle* /*column_family*/, const Slice& /*key*/,
const Slice& /*value*/) override {
return Status::NotSupported("Not supported operation in read only mode.");
}
using DBImpl::Merge;
Status Merge(const WriteOptions& /*options*/,
ColumnFamilyHandle* /*column_family*/, const Slice& /*key*/,
const Slice& /*value*/) override {
return Status::NotSupported("Not supported operation in read only mode.");
}
using DBImpl::Delete;
Status Delete(const WriteOptions& /*options*/,
ColumnFamilyHandle* /*column_family*/,
const Slice& /*key*/) override {
return Status::NotSupported("Not supported operation in read only mode.");
}
using DBImpl::SingleDelete;
Status SingleDelete(const WriteOptions& /*options*/,
ColumnFamilyHandle* /*column_family*/,
const Slice& /*key*/) override {
return Status::NotSupported("Not supported operation in read only mode.");
}
Status Write(const WriteOptions& /*options*/,
WriteBatch* /*updates*/) override {
return Status::NotSupported("Not supported operation in read only mode.");
}
using DBImpl::CompactRange;
Status CompactRange(const CompactRangeOptions& /*options*/,
ColumnFamilyHandle* /*column_family*/,
const Slice* /*begin*/, const Slice* /*end*/) override {
return Status::NotSupported("Not supported operation in read only mode.");
}
using DBImpl::CompactFiles;
Status CompactFiles(
const CompactionOptions& /*compact_options*/,
ColumnFamilyHandle* /*column_family*/,
const std::vector<std::string>& /*input_file_names*/,
const int /*output_level*/, const int /*output_path_id*/ = -1,
std::vector<std::string>* const /*output_file_names*/ = nullptr,
CompactionJobInfo* /*compaction_job_info*/ = nullptr) override {
return Status::NotSupported("Not supported operation in read only mode.");
}
Status DisableFileDeletions() override {
return Status::NotSupported("Not supported operation in read only mode.");
}
Status EnableFileDeletions(bool /*force*/) override {
return Status::NotSupported("Not supported operation in read only mode.");
}
Status GetLiveFiles(std::vector<std::string>&,
uint64_t* /*manifest_file_size*/,
bool /*flush_memtable*/ = true) override {
return Status::NotSupported("Not supported operation in read only mode.");
}
using DBImpl::Flush;
Status Flush(const FlushOptions& /*options*/,
ColumnFamilyHandle* /*column_family*/) override {
return Status::NotSupported("Not supported operation in read only mode.");
}
using DBImpl::SyncWAL;
Status SyncWAL() override {
return Status::NotSupported("Not supported operation in read only mode.");
}
using DB::IngestExternalFile;
Status IngestExternalFile(
ColumnFamilyHandle* /*column_family*/,
const std::vector<std::string>& /*external_files*/,
const IngestExternalFileOptions& /*ingestion_options*/) override {
return Status::NotSupported("Not supported operation in read only mode.");
}
// Try to catch up with the primary by reading as much as possible from the
// log files until there is nothing more to read or encounters an error. If
// the amount of information in the log files to process is huge, this
// method can take long time due to all the I/O and CPU costs.
Status TryCatchUpWithPrimary() override;
private:
friend class DB;
// No copying allowed
DBImplSecondary(const DBImplSecondary&);
void operator=(const DBImplSecondary&);
using DBImpl::Recover;
std::unique_ptr<log::FragmentBufferedReader> manifest_reader_;
std::unique_ptr<log::Reader::Reporter> manifest_reporter_;
std::unique_ptr<Status> manifest_reader_status_;
};
} // namespace rocksdb
#endif // !ROCKSDB_LITE

480
db/db_secondary_test.cc Normal file
View File

@ -0,0 +1,480 @@
// Copyright (c) 2011-present, Facebook, Inc. All rights reserved.
// This source code is licensed under both the GPLv2 (found in the
// COPYING file in the root directory) and Apache 2.0 License
// (found in the LICENSE.Apache file in the root directory).
//
// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file. See the AUTHORS file for names of contributors.
#include "db/db_impl_secondary.h"
#include "db/db_test_util.h"
#include "port/stack_trace.h"
#include "util/fault_injection_test_env.h"
#include "util/sync_point.h"
namespace rocksdb {
#ifndef ROCKSDB_LITE
class DBSecondaryTest : public DBTestBase {
public:
DBSecondaryTest()
: DBTestBase("/db_secondary_test"),
secondary_path_(),
handles_secondary_(),
db_secondary_(nullptr) {
secondary_path_ =
test::PerThreadDBPath(env_, "/db_secondary_test_secondary");
}
~DBSecondaryTest() override {
CloseSecondary();
if (getenv("KEEP_DB") != nullptr) {
fprintf(stdout, "Secondary DB is still at %s\n", secondary_path_.c_str());
} else {
Options options;
options.env = env_;
EXPECT_OK(DestroyDB(secondary_path_, options));
}
}
protected:
Status ReopenAsSecondary(const Options& options) {
return DB::OpenAsSecondary(options, dbname_, secondary_path_, &db_);
}
void OpenSecondary(const Options& options);
void OpenSecondaryWithColumnFamilies(
const std::vector<std::string>& column_families, const Options& options);
void CloseSecondary() {
for (auto h : handles_secondary_) {
db_secondary_->DestroyColumnFamilyHandle(h);
}
handles_secondary_.clear();
delete db_secondary_;
db_secondary_ = nullptr;
}
DBImplSecondary* db_secondary_full() {
return static_cast<DBImplSecondary*>(db_secondary_);
}
void CheckFileTypeCounts(const std::string& dir, int expected_log,
int expected_sst, int expected_manifest) const;
std::string secondary_path_;
std::vector<ColumnFamilyHandle*> handles_secondary_;
DB* db_secondary_;
};
void DBSecondaryTest::OpenSecondary(const Options& options) {
Status s =
DB::OpenAsSecondary(options, dbname_, secondary_path_, &db_secondary_);
ASSERT_OK(s);
}
void DBSecondaryTest::OpenSecondaryWithColumnFamilies(
const std::vector<std::string>& column_families, const Options& options) {
std::vector<ColumnFamilyDescriptor> cf_descs;
cf_descs.emplace_back(kDefaultColumnFamilyName, options);
for (const auto& cf_name : column_families) {
cf_descs.emplace_back(cf_name, options);
}
Status s = DB::OpenAsSecondary(options, dbname_, secondary_path_, cf_descs,
&handles_secondary_, &db_secondary_);
ASSERT_OK(s);
}
void DBSecondaryTest::CheckFileTypeCounts(const std::string& dir,
int expected_log, int expected_sst,
int expected_manifest) const {
std::vector<std::string> filenames;
env_->GetChildren(dir, &filenames);
int log_cnt = 0, sst_cnt = 0, manifest_cnt = 0;
for (auto file : filenames) {
uint64_t number;
FileType type;
if (ParseFileName(file, &number, &type)) {
log_cnt += (type == kLogFile);
sst_cnt += (type == kTableFile);
manifest_cnt += (type == kDescriptorFile);
}
}
ASSERT_EQ(expected_log, log_cnt);
ASSERT_EQ(expected_sst, sst_cnt);
ASSERT_EQ(expected_manifest, manifest_cnt);
}
TEST_F(DBSecondaryTest, ReopenAsSecondary) {
Options options;
options.env = env_;
Reopen(options);
ASSERT_OK(Put("foo", "foo_value"));
ASSERT_OK(Put("bar", "bar_value"));
ASSERT_OK(dbfull()->Flush(FlushOptions()));
Close();
ASSERT_OK(ReopenAsSecondary(options));
ASSERT_EQ("foo_value", Get("foo"));
ASSERT_EQ("bar_value", Get("bar"));
ReadOptions ropts;
ropts.verify_checksums = true;
auto db1 = static_cast<DBImplSecondary*>(db_);
ASSERT_NE(nullptr, db1);
Iterator* iter = db1->NewIterator(ropts);
ASSERT_NE(nullptr, iter);
size_t count = 0;
for (iter->SeekToFirst(); iter->Valid(); iter->Next()) {
if (0 == count) {
ASSERT_EQ("bar", iter->key().ToString());
ASSERT_EQ("bar_value", iter->value().ToString());
} else if (1 == count) {
ASSERT_EQ("foo", iter->key().ToString());
ASSERT_EQ("foo_value", iter->value().ToString());
}
++count;
}
delete iter;
ASSERT_EQ(2, count);
}
TEST_F(DBSecondaryTest, OpenAsSecondary) {
Options options;
options.env = env_;
options.level0_file_num_compaction_trigger = 4;
Reopen(options);
for (int i = 0; i < 3; ++i) {
ASSERT_OK(Put("foo", "foo_value" + std::to_string(i)));
ASSERT_OK(Put("bar", "bar_value" + std::to_string(i)));
ASSERT_OK(Flush());
}
Options options1;
options1.env = env_;
options1.max_open_files = -1;
OpenSecondary(options1);
ASSERT_OK(dbfull()->CompactRange(CompactRangeOptions(), nullptr, nullptr));
ASSERT_OK(dbfull()->TEST_WaitForCompact());
ReadOptions ropts;
ropts.verify_checksums = true;
const auto verify_db_func = [&](const std::string& foo_val,
const std::string& bar_val) {
std::string value;
ASSERT_OK(db_secondary_->Get(ropts, "foo", &value));
ASSERT_EQ(foo_val, value);
ASSERT_OK(db_secondary_->Get(ropts, "bar", &value));
ASSERT_EQ(bar_val, value);
Iterator* iter = db_secondary_->NewIterator(ropts);
ASSERT_NE(nullptr, iter);
iter->Seek("foo");
ASSERT_TRUE(iter->Valid());
ASSERT_EQ("foo", iter->key().ToString());
ASSERT_EQ(foo_val, iter->value().ToString());
iter->Seek("bar");
ASSERT_TRUE(iter->Valid());
ASSERT_EQ("bar", iter->key().ToString());
ASSERT_EQ(bar_val, iter->value().ToString());
size_t count = 0;
for (iter->SeekToFirst(); iter->Valid(); iter->Next()) {
++count;
}
ASSERT_EQ(2, count);
delete iter;
};
verify_db_func("foo_value2", "bar_value2");
ASSERT_OK(Put("foo", "new_foo_value"));
ASSERT_OK(Put("bar", "new_bar_value"));
ASSERT_OK(Flush());
ASSERT_OK(db_secondary_->TryCatchUpWithPrimary());
verify_db_func("new_foo_value", "new_bar_value");
}
TEST_F(DBSecondaryTest, OpenWithNonExistColumnFamily) {
Options options;
options.env = env_;
CreateAndReopenWithCF({"pikachu"}, options);
Options options1;
options1.env = env_;
options1.max_open_files = -1;
std::vector<ColumnFamilyDescriptor> cf_descs;
cf_descs.emplace_back(kDefaultColumnFamilyName, options1);
cf_descs.emplace_back("pikachu", options1);
cf_descs.emplace_back("eevee", options1);
Status s = DB::OpenAsSecondary(options1, dbname_, secondary_path_, cf_descs,
&handles_secondary_, &db_secondary_);
ASSERT_NOK(s);
}
TEST_F(DBSecondaryTest, OpenWithSubsetOfColumnFamilies) {
Options options;
options.env = env_;
CreateAndReopenWithCF({"pikachu"}, options);
Options options1;
options1.env = env_;
options1.max_open_files = -1;
OpenSecondary(options1);
ASSERT_EQ(0, handles_secondary_.size());
ASSERT_NE(nullptr, db_secondary_);
ASSERT_OK(Put(0 /*cf*/, "foo", "foo_value"));
ASSERT_OK(Put(1 /*cf*/, "foo", "foo_value"));
ASSERT_OK(Flush(0 /*cf*/));
ASSERT_OK(Flush(1 /*cf*/));
ASSERT_OK(db_secondary_->TryCatchUpWithPrimary());
ReadOptions ropts;
ropts.verify_checksums = true;
std::string value;
ASSERT_OK(db_secondary_->Get(ropts, "foo", &value));
ASSERT_EQ("foo_value", value);
}
TEST_F(DBSecondaryTest, SwitchToNewManifestDuringOpen) {
Options options;
options.env = env_;
Reopen(options);
Close();
SyncPoint::GetInstance()->DisableProcessing();
SyncPoint::GetInstance()->ClearAllCallBacks();
SyncPoint::GetInstance()->LoadDependency(
{{"ReactiveVersionSet::MaybeSwitchManifest:AfterGetCurrentManifestPath:0",
"VersionSet::ProcessManifestWrites:BeforeNewManifest"},
{"VersionSet::ProcessManifestWrites:AfterNewManifest",
"ReactiveVersionSet::MaybeSwitchManifest:AfterGetCurrentManifestPath:"
"1"}});
SyncPoint::GetInstance()->EnableProcessing();
// Make sure db calls RecoverLogFiles so as to trigger a manifest write,
// which causes the db to switch to a new MANIFEST upon start.
port::Thread ro_db_thread([&]() {
Options options1;
options1.env = env_;
options1.max_open_files = -1;
OpenSecondary(options1);
CloseSecondary();
});
Reopen(options);
ro_db_thread.join();
}
TEST_F(DBSecondaryTest, MissingTableFileDuringOpen) {
Options options;
options.env = env_;
options.level0_file_num_compaction_trigger = 4;
Reopen(options);
for (int i = 0; i != options.level0_file_num_compaction_trigger; ++i) {
ASSERT_OK(Put("foo", "foo_value" + std::to_string(i)));
ASSERT_OK(Put("bar", "bar_value" + std::to_string(i)));
ASSERT_OK(dbfull()->Flush(FlushOptions()));
}
ASSERT_OK(dbfull()->TEST_WaitForFlushMemTable());
ASSERT_OK(dbfull()->TEST_WaitForCompact());
Options options1;
options1.env = env_;
options1.max_open_files = -1;
OpenSecondary(options1);
ReadOptions ropts;
ropts.verify_checksums = true;
std::string value;
ASSERT_OK(db_secondary_->Get(ropts, "foo", &value));
ASSERT_EQ("foo_value" +
std::to_string(options.level0_file_num_compaction_trigger - 1),
value);
ASSERT_OK(db_secondary_->Get(ropts, "bar", &value));
ASSERT_EQ("bar_value" +
std::to_string(options.level0_file_num_compaction_trigger - 1),
value);
Iterator* iter = db_secondary_->NewIterator(ropts);
ASSERT_NE(nullptr, iter);
iter->Seek("bar");
ASSERT_TRUE(iter->Valid());
ASSERT_EQ("bar", iter->key().ToString());
ASSERT_EQ("bar_value" +
std::to_string(options.level0_file_num_compaction_trigger - 1),
iter->value().ToString());
iter->Seek("foo");
ASSERT_TRUE(iter->Valid());
ASSERT_EQ("foo", iter->key().ToString());
ASSERT_EQ("foo_value" +
std::to_string(options.level0_file_num_compaction_trigger - 1),
iter->value().ToString());
size_t count = 0;
for (iter->SeekToFirst(); iter->Valid(); iter->Next()) {
++count;
}
ASSERT_EQ(2, count);
delete iter;
}
TEST_F(DBSecondaryTest, MissingTableFile) {
int table_files_not_exist = 0;
SyncPoint::GetInstance()->DisableProcessing();
SyncPoint::GetInstance()->ClearAllCallBacks();
SyncPoint::GetInstance()->SetCallBack(
"ReactiveVersionSet::ReadAndApply:AfterLoadTableHandlers",
[&](void* arg) {
Status s = *reinterpret_cast<Status*>(arg);
if (s.IsPathNotFound()) {
++table_files_not_exist;
} else if (!s.ok()) {
assert(false); // Should not reach here
}
});
SyncPoint::GetInstance()->EnableProcessing();
Options options;
options.env = env_;
options.level0_file_num_compaction_trigger = 4;
Reopen(options);
Options options1;
options1.env = env_;
options1.max_open_files = -1;
OpenSecondary(options1);
for (int i = 0; i != options.level0_file_num_compaction_trigger; ++i) {
ASSERT_OK(Put("foo", "foo_value" + std::to_string(i)));
ASSERT_OK(Put("bar", "bar_value" + std::to_string(i)));
ASSERT_OK(dbfull()->Flush(FlushOptions()));
}
ASSERT_OK(dbfull()->TEST_WaitForFlushMemTable());
ASSERT_OK(dbfull()->TEST_WaitForCompact());
ASSERT_NE(nullptr, db_secondary_full());
ReadOptions ropts;
ropts.verify_checksums = true;
std::string value;
ASSERT_NOK(db_secondary_->Get(ropts, "foo", &value));
ASSERT_NOK(db_secondary_->Get(ropts, "bar", &value));
ASSERT_OK(db_secondary_->TryCatchUpWithPrimary());
ASSERT_EQ(options.level0_file_num_compaction_trigger, table_files_not_exist);
ASSERT_OK(db_secondary_->Get(ropts, "foo", &value));
ASSERT_EQ("foo_value" +
std::to_string(options.level0_file_num_compaction_trigger - 1),
value);
ASSERT_OK(db_secondary_->Get(ropts, "bar", &value));
ASSERT_EQ("bar_value" +
std::to_string(options.level0_file_num_compaction_trigger - 1),
value);
Iterator* iter = db_secondary_->NewIterator(ropts);
ASSERT_NE(nullptr, iter);
iter->Seek("bar");
ASSERT_TRUE(iter->Valid());
ASSERT_EQ("bar", iter->key().ToString());
ASSERT_EQ("bar_value" +
std::to_string(options.level0_file_num_compaction_trigger - 1),
iter->value().ToString());
iter->Seek("foo");
ASSERT_TRUE(iter->Valid());
ASSERT_EQ("foo", iter->key().ToString());
ASSERT_EQ("foo_value" +
std::to_string(options.level0_file_num_compaction_trigger - 1),
iter->value().ToString());
size_t count = 0;
for (iter->SeekToFirst(); iter->Valid(); iter->Next()) {
++count;
}
ASSERT_EQ(2, count);
delete iter;
}
TEST_F(DBSecondaryTest, PrimaryDropColumnFamily) {
Options options;
options.env = env_;
const std::string kCfName1 = "pikachu";
CreateAndReopenWithCF({kCfName1}, options);
Options options1;
options1.env = env_;
options1.max_open_files = -1;
OpenSecondaryWithColumnFamilies({kCfName1}, options1);
ASSERT_EQ(2, handles_secondary_.size());
ASSERT_OK(Put(1 /*cf*/, "foo", "foo_val_1"));
ASSERT_OK(Flush(1 /*cf*/));
ASSERT_OK(db_secondary_->TryCatchUpWithPrimary());
ReadOptions ropts;
ropts.verify_checksums = true;
std::string value;
ASSERT_OK(db_secondary_->Get(ropts, handles_secondary_[1], "foo", &value));
ASSERT_EQ("foo_val_1", value);
ASSERT_OK(dbfull()->DropColumnFamily(handles_[1]));
Close();
CheckFileTypeCounts(dbname_, 1, 0, 1);
ASSERT_OK(db_secondary_->TryCatchUpWithPrimary());
value.clear();
ASSERT_OK(db_secondary_->Get(ropts, handles_secondary_[1], "foo", &value));
ASSERT_EQ("foo_val_1", value);
}
TEST_F(DBSecondaryTest, SwitchManifest) {
Options options;
options.env = env_;
options.level0_file_num_compaction_trigger = 4;
Reopen(options);
Options options1;
options1.env = env_;
options1.max_open_files = -1;
OpenSecondary(options1);
const int kNumFiles = options.level0_file_num_compaction_trigger - 1;
// Keep it smaller than 10 so that key0, key1, ..., key9 are sorted as 0, 1,
// ..., 9.
const int kNumKeys = 10;
// Create two sst
for (int i = 0; i != kNumFiles; ++i) {
for (int j = 0; j != kNumKeys; ++j) {
ASSERT_OK(Put("key" + std::to_string(j), "value_" + std::to_string(i)));
}
ASSERT_OK(Flush());
}
ASSERT_OK(db_secondary_->TryCatchUpWithPrimary());
const auto& range_scan_db = [&]() {
ReadOptions tmp_ropts;
tmp_ropts.total_order_seek = true;
tmp_ropts.verify_checksums = true;
std::unique_ptr<Iterator> iter(db_secondary_->NewIterator(tmp_ropts));
int cnt = 0;
for (iter->SeekToFirst(); iter->Valid(); iter->Next(), ++cnt) {
ASSERT_EQ("key" + std::to_string(cnt), iter->key().ToString());
ASSERT_EQ("value_" + std::to_string(kNumFiles - 1),
iter->value().ToString());
}
};
range_scan_db();
// While secondary instance still keeps old MANIFEST open, we close primary,
// restart primary, performs full compaction, close again, restart again so
// that next time secondary tries to catch up with primary, the secondary
// will skip the MANIFEST in middle.
Reopen(options);
ASSERT_OK(dbfull()->CompactRange(CompactRangeOptions(), nullptr, nullptr));
ASSERT_OK(dbfull()->TEST_WaitForCompact());
Reopen(options);
ASSERT_OK(dbfull()->SetOptions({{"disable_auto_compactions", "false"}}));
ASSERT_OK(db_secondary_->TryCatchUpWithPrimary());
range_scan_db();
}
#endif //! ROCKSDB_LITE
} // namespace rocksdb
int main(int argc, char** argv) {
rocksdb::port::InstallStackTraceHandler();
::testing::InitGoogleTest(&argc, argv);
return RUN_ALL_TESTS();
}

270
db/log_reader.cc
View File

@ -24,8 +24,7 @@ Reader::Reporter::~Reporter() {
Reader::Reader(std::shared_ptr<Logger> info_log,
std::unique_ptr<SequentialFileReader>&& _file,
Reporter* reporter, bool checksum, uint64_t log_num,
bool retry_after_eof)
Reporter* reporter, bool checksum, uint64_t log_num)
: info_log_(info_log),
file_(std::move(_file)),
reporter_(reporter),
@ -38,8 +37,7 @@ Reader::Reader(std::shared_ptr<Logger> info_log,
last_record_offset_(0),
end_of_buffer_offset_(0),
log_number_(log_num),
recycled_(false),
retry_after_eof_(retry_after_eof) {}
recycled_(false) {}
Reader::~Reader() {
delete[] backing_store_;
@ -207,14 +205,14 @@ void Reader::UnmarkEOF() {
if (read_error_) {
return;
}
eof_ = false;
// If retry_after_eof_ is true, we have to proceed to read anyway.
if (!retry_after_eof_ && eof_offset_ == 0) {
if (eof_offset_ == 0) {
return;
}
UnmarkEOFInternal();
}
void Reader::UnmarkEOFInternal() {
// If the EOF was in the middle of a block (a partial block was read) we have
// to read the rest of the block as ReadPhysicalRecord can only read full
// blocks and expects the file position indicator to be aligned to the start
@ -292,12 +290,8 @@ bool Reader::ReadMore(size_t* drop_size, int *error) {
} else if (buffer_.size() < static_cast<size_t>(kBlockSize)) {
eof_ = true;
eof_offset_ = buffer_.size();
TEST_SYNC_POINT("LogReader::ReadMore:FirstEOF");
}
return true;
} else if (retry_after_eof_ && !read_error_) {
UnmarkEOF();
return !read_error_;
} else {
// Note that if buffer_ is non-empty, we have a truncated header at the
// end of the file, which can be caused by the writer crashing in the
@ -355,24 +349,16 @@ unsigned int Reader::ReadPhysicalRecord(Slice* result, size_t* drop_size) {
}
}
if (header_size + length > buffer_.size()) {
if (!retry_after_eof_) {
*drop_size = buffer_.size();
buffer_.clear();
if (!eof_) {
return kBadRecordLen;
}
// If the end of the file has been reached without reading |length|
// bytes of payload, assume the writer died in the middle of writing the
// record. Don't report a corruption unless requested.
if (*drop_size) {
return kBadHeader;
}
} else {
int r = kEof;
if (!ReadMore(drop_size, &r)) {
return r;
}
continue;
*drop_size = buffer_.size();
buffer_.clear();
if (!eof_) {
return kBadRecordLen;
}
// If the end of the file has been reached without reading |length|
// bytes of payload, assume the writer died in the middle of writing the
// record. Don't report a corruption unless requested.
if (*drop_size) {
return kBadHeader;
}
return kEof;
}
@ -409,5 +395,229 @@ unsigned int Reader::ReadPhysicalRecord(Slice* result, size_t* drop_size) {
}
}
bool FragmentBufferedReader::ReadRecord(Slice* record, std::string* scratch,
WALRecoveryMode /*unused*/) {
assert(record != nullptr);
assert(scratch != nullptr);
record->clear();
scratch->clear();
uint64_t prospective_record_offset = 0;
uint64_t physical_record_offset = end_of_buffer_offset_ - buffer_.size();
size_t drop_size = 0;
unsigned int fragment_type_or_err = 0; // Initialize to make compiler happy
Slice fragment;
while (TryReadFragment(&fragment, &drop_size, &fragment_type_or_err)) {
switch (fragment_type_or_err) {
case kFullType:
case kRecyclableFullType:
if (in_fragmented_record_ && !fragments_.empty()) {
ReportCorruption(fragments_.size(), "partial record without end(1)");
}
fragments_.clear();
*record = fragment;
prospective_record_offset = physical_record_offset;
last_record_offset_ = prospective_record_offset;
in_fragmented_record_ = false;
return true;
case kFirstType:
case kRecyclableFirstType:
if (in_fragmented_record_ || !fragments_.empty()) {
ReportCorruption(fragments_.size(), "partial record without end(2)");
}
prospective_record_offset = physical_record_offset;
fragments_.assign(fragment.data(), fragment.size());
in_fragmented_record_ = true;
break;
case kMiddleType:
case kRecyclableMiddleType:
if (!in_fragmented_record_) {
ReportCorruption(fragment.size(),
"missing start of fragmented record(1)");
} else {
fragments_.append(fragment.data(), fragment.size());
}
break;
case kLastType:
case kRecyclableLastType:
if (!in_fragmented_record_) {
ReportCorruption(fragment.size(),
"missing start of fragmented record(2)");
} else {
fragments_.append(fragment.data(), fragment.size());
scratch->assign(fragments_.data(), fragments_.size());
fragments_.clear();
*record = Slice(*scratch);
last_record_offset_ = prospective_record_offset;
in_fragmented_record_ = false;
return true;
}
break;
case kBadHeader:
case kBadRecord:
case kEof:
case kOldRecord:
if (in_fragmented_record_) {
ReportCorruption(fragments_.size(), "error in middle of record");
in_fragmented_record_ = false;
fragments_.clear();
}
break;
case kBadRecordChecksum:
if (recycled_) {
fragments_.clear();
return false;
}
ReportCorruption(drop_size, "checksum mismatch");
if (in_fragmented_record_) {
ReportCorruption(fragments_.size(), "error in middle of record");
in_fragmented_record_ = false;
fragments_.clear();
}
break;
default: {
char buf[40];
snprintf(buf, sizeof(buf), "unknown record type %u",
fragment_type_or_err);
ReportCorruption(
fragment.size() + (in_fragmented_record_ ? fragments_.size() : 0),
buf);
in_fragmented_record_ = false;
fragments_.clear();
break;
}
}
}
return false;
}
void FragmentBufferedReader::UnmarkEOF() {
if (read_error_) {
return;
}
eof_ = false;
UnmarkEOFInternal();
}
bool FragmentBufferedReader::TryReadMore(size_t* drop_size, int* error) {
if (!eof_ && !read_error_) {
// Last read was a full read, so this is a trailer to skip
buffer_.clear();
Status status = file_->Read(kBlockSize, &buffer_, backing_store_);
end_of_buffer_offset_ += buffer_.size();
if (!status.ok()) {
buffer_.clear();
ReportDrop(kBlockSize, status);
read_error_ = true;
*error = kEof;
return false;
} else if (buffer_.size() < static_cast<size_t>(kBlockSize)) {
eof_ = true;
eof_offset_ = buffer_.size();
TEST_SYNC_POINT_CALLBACK(
"FragmentBufferedLogReader::TryReadMore:FirstEOF", nullptr);
}
return true;
} else if (!read_error_) {
UnmarkEOF();
}
if (!read_error_) {
return true;
}
*error = kEof;
*drop_size = buffer_.size();
if (buffer_.size() > 0) {
*error = kBadHeader;
}
buffer_.clear();
return false;
}
// return true if the caller should process the fragment_type_or_err.
bool FragmentBufferedReader::TryReadFragment(
Slice* fragment, size_t* drop_size, unsigned int* fragment_type_or_err) {
assert(fragment != nullptr);
assert(drop_size != nullptr);
assert(fragment_type_or_err != nullptr);
while (buffer_.size() < static_cast<size_t>(kHeaderSize)) {
size_t old_size = buffer_.size();
int error = kEof;
if (!TryReadMore(drop_size, &error)) {
*fragment_type_or_err = error;
return false;
} else if (old_size == buffer_.size()) {
return false;
}
}
const char* header = buffer_.data();
const uint32_t a = static_cast<uint32_t>(header[4]) & 0xff;
const uint32_t b = static_cast<uint32_t>(header[5]) & 0xff;
const unsigned int type = header[6];
const uint32_t length = a | (b << 8);
int header_size = kHeaderSize;
if (type >= kRecyclableFullType && type <= kRecyclableLastType) {
if (end_of_buffer_offset_ - buffer_.size() == 0) {
recycled_ = true;
}
header_size = kRecyclableHeaderSize;
while (buffer_.size() < static_cast<size_t>(kRecyclableHeaderSize)) {
size_t old_size = buffer_.size();
int error = kEof;
if (!TryReadMore(drop_size, &error)) {
*fragment_type_or_err = error;
return false;
} else if (old_size == buffer_.size()) {
return false;
}
}
const uint32_t log_num = DecodeFixed32(header + 7);
if (log_num != log_number_) {
*fragment_type_or_err = kOldRecord;
return true;
}
}
while (header_size + length > buffer_.size()) {
size_t old_size = buffer_.size();
int error = kEof;
if (!TryReadMore(drop_size, &error)) {
*fragment_type_or_err = error;
return false;
} else if (old_size == buffer_.size()) {
return false;
}
}
if (type == kZeroType && length == 0) {
buffer_.clear();
*fragment_type_or_err = kBadRecord;
return true;
}
if (checksum_) {
uint32_t expected_crc = crc32c::Unmask(DecodeFixed32(header));
uint32_t actual_crc = crc32c::Value(header + 6, length + header_size - 6);
if (actual_crc != expected_crc) {
*drop_size = buffer_.size();
buffer_.clear();
*fragment_type_or_err = kBadRecordChecksum;
return true;
}
}
buffer_.remove_prefix(header_size + length);
*fragment = Slice(header + header_size, length);
*fragment_type_or_err = type;
return true;
}
} // namespace log
} // namespace rocksdb

58
db/log_reader.h
View File

@ -53,18 +53,18 @@ class Reader {
Reader(std::shared_ptr<Logger> info_log,
// @lint-ignore TXT2 T25377293 Grandfathered in
std::unique_ptr<SequentialFileReader>&& file, Reporter* reporter,
bool checksum, uint64_t log_num, bool retry_after_eof);
bool checksum, uint64_t log_num);
~Reader();
virtual ~Reader();
// Read the next record into *record. Returns true if read
// successfully, false if we hit end of the input. May use
// "*scratch" as temporary storage. The contents filled in *record
// will only be valid until the next mutating operation on this
// reader or the next mutation to *scratch.
bool ReadRecord(Slice* record, std::string* scratch,
WALRecoveryMode wal_recovery_mode =
WALRecoveryMode::kTolerateCorruptedTailRecords);
virtual bool ReadRecord(Slice* record, std::string* scratch,
WALRecoveryMode wal_recovery_mode =
WALRecoveryMode::kTolerateCorruptedTailRecords);
// Returns the physical offset of the last record returned by ReadRecord.
//
@ -76,21 +76,28 @@ class Reader {
return eof_;
}
// returns true if the reader has encountered read error.
bool hasReadError() const { return read_error_; }
// when we know more data has been written to the file. we can use this
// function to force the reader to look again in the file.
// Also aligns the file position indicator to the start of the next block
// by reading the rest of the data from the EOF position to the end of the
// block that was partially read.
void UnmarkEOF();
virtual void UnmarkEOF();
SequentialFileReader* file() { return file_.get(); }
private:
Reporter* GetReporter() const { return reporter_; }
protected:
std::shared_ptr<Logger> info_log_;
const std::unique_ptr<SequentialFileReader> file_;
Reporter* const reporter_;
bool const checksum_;
char* const backing_store_;
// Internal state variables used for reading records
Slice buffer_;
bool eof_; // Last Read() indicated EOF by returning < kBlockSize
bool read_error_; // Error occurred while reading from file
@ -110,11 +117,6 @@ class Reader {
// Whether this is a recycled log file
bool recycled_;
// Whether retry after encountering EOF
// TODO (yanqin) add support for retry policy, e.g. sleep, max retry limit,
// etc.
const bool retry_after_eof_;
// Extend record types with the following special values
enum {
kEof = kMaxRecordType + 1,
@ -139,15 +141,47 @@ class Reader {
// Read some more
bool ReadMore(size_t* drop_size, int *error);
void UnmarkEOFInternal();
// Reports dropped bytes to the reporter.
// buffer_ must be updated to remove the dropped bytes prior to invocation.
void ReportCorruption(size_t bytes, const char* reason);
void ReportDrop(size_t bytes, const Status& reason);
private:
// No copying allowed
Reader(const Reader&);
void operator=(const Reader&);
};
class FragmentBufferedReader : public Reader {
public:
FragmentBufferedReader(std::shared_ptr<Logger> info_log,
// @lint-ignore TXT2 T25377293 Grandfathered in
std::unique_ptr<SequentialFileReader>&& _file,
Reporter* reporter, bool checksum, uint64_t log_num)
: Reader(info_log, std::move(_file), reporter, checksum, log_num),
fragments_(),
in_fragmented_record_(false) {}
~FragmentBufferedReader() override {}
bool ReadRecord(Slice* record, std::string* scratch,
WALRecoveryMode wal_recovery_mode =
WALRecoveryMode::kTolerateCorruptedTailRecords) override;
void UnmarkEOF() override;
private:
std::string fragments_;
bool in_fragmented_record_;
bool TryReadFragment(Slice* result, size_t* drop_size,
unsigned int* fragment_type_or_err);
bool TryReadMore(size_t* drop_size, int* error);
// No copy allowed
FragmentBufferedReader(const FragmentBufferedReader&);
void operator=(const FragmentBufferedReader&);
};
} // namespace log
} // namespace rocksdb

252
db/log_test.cc
View File

@ -43,7 +43,10 @@ static std::string RandomSkewedString(int i, Random* rnd) {
return BigString(NumberString(i), rnd->Skewed(17));
}
class LogTest : public ::testing::TestWithParam<int> {
// Param type is tuple<int, bool>
// get<0>(tuple): non-zero if recycling log, zero if regular log
// get<1>(tuple): true if allow retry after read EOF, false otherwise
class LogTest : public ::testing::TestWithParam<std::tuple<int, bool>> {
private:
class StringSource : public SequentialFile {
public:
@ -53,16 +56,20 @@ class LogTest : public ::testing::TestWithParam<int> {
bool force_eof_;
size_t force_eof_position_;
bool returned_partial_;
explicit StringSource(Slice& contents) :
contents_(contents),
force_error_(false),
force_error_position_(0),
force_eof_(false),
force_eof_position_(0),
returned_partial_(false) { }
bool fail_after_read_partial_;
explicit StringSource(Slice& contents, bool fail_after_read_partial)
: contents_(contents),
force_error_(false),
force_error_position_(0),
force_eof_(false),
force_eof_position_(0),
returned_partial_(false),
fail_after_read_partial_(fail_after_read_partial) {}
Status Read(size_t n, Slice* result, char* scratch) override {
EXPECT_TRUE(!returned_partial_) << "must not Read() after eof/error";
if (fail_after_read_partial_) {
EXPECT_TRUE(!returned_partial_) << "must not Read() after eof/error";
}
if (force_error_) {
if (force_error_position_ >= n) {
@ -139,7 +146,7 @@ class LogTest : public ::testing::TestWithParam<int> {
}
void reset_source_contents() {
auto src = dynamic_cast<StringSource*>(reader_.file()->file());
auto src = dynamic_cast<StringSource*>(reader_->file()->file());
assert(src);
src->contents_ = dest_contents();
}
@ -149,11 +156,10 @@ class LogTest : public ::testing::TestWithParam<int> {
std::unique_ptr<SequentialFileReader> source_holder_;
ReportCollector report_;
Writer writer_;
Reader reader_;
std::unique_ptr<Reader> reader_;
// Record metadata for testing initial offset functionality
static size_t initial_offset_record_sizes_[];
uint64_t initial_offset_last_record_offsets_[4];
protected:
bool allow_retry_read_;
public:
LogTest()
@ -161,18 +167,18 @@ class LogTest : public ::testing::TestWithParam<int> {
dest_holder_(test::GetWritableFileWriter(
new test::StringSink(&reader_contents_), "" /* don't care */)),
source_holder_(test::GetSequentialFileReader(
new StringSource(reader_contents_), "" /* file name */)),
writer_(std::move(dest_holder_), 123, GetParam()),
reader_(nullptr, std::move(source_holder_), &report_,
true /* checksum */, 123 /* log_number */,
false /* retry_after_eof */) {
int header_size = GetParam() ? kRecyclableHeaderSize : kHeaderSize;
initial_offset_last_record_offsets_[0] = 0;
initial_offset_last_record_offsets_[1] = header_size + 10000;
initial_offset_last_record_offsets_[2] = 2 * (header_size + 10000);
initial_offset_last_record_offsets_[3] = 2 * (header_size + 10000) +
(2 * log::kBlockSize - 1000) +
3 * header_size;
new StringSource(reader_contents_, !std::get<1>(GetParam())),
"" /* file name */)),
writer_(std::move(dest_holder_), 123, std::get<0>(GetParam())),
allow_retry_read_(std::get<1>(GetParam())) {
if (allow_retry_read_) {
reader_.reset(new FragmentBufferedReader(
nullptr, std::move(source_holder_), &report_, true /* checksum */,
123 /* log_number */));
} else {
reader_.reset(new Reader(nullptr, std::move(source_holder_), &report_,
true /* checksum */, 123 /* log_number */));
}
}
Slice* get_reader_contents() { return &reader_contents_; }
@ -189,7 +195,9 @@ class LogTest : public ::testing::TestWithParam<int> {
WALRecoveryMode::kTolerateCorruptedTailRecords) {
std::string scratch;
Slice record;
if (reader_.ReadRecord(&record, &scratch, wal_recovery_mode)) {
bool ret = false;
ret = reader_->ReadRecord(&record, &scratch, wal_recovery_mode);
if (ret) {
return record.ToString();
} else {
return "EOF";
@ -221,7 +229,7 @@ class LogTest : public ::testing::TestWithParam<int> {
}
void ForceError(size_t position = 0) {
auto src = dynamic_cast<StringSource*>(reader_.file()->file());
auto src = dynamic_cast<StringSource*>(reader_->file()->file());
src->force_error_ = true;
src->force_error_position_ = position;
}
@ -235,20 +243,18 @@ class LogTest : public ::testing::TestWithParam<int> {
}
void ForceEOF(size_t position = 0) {
auto src = dynamic_cast<StringSource*>(reader_.file()->file());
auto src = dynamic_cast<StringSource*>(reader_->file()->file());
src->force_eof_ = true;
src->force_eof_position_ = position;
}
void UnmarkEOF() {
auto src = dynamic_cast<StringSource*>(reader_.file()->file());
auto src = dynamic_cast<StringSource*>(reader_->file()->file());
src->returned_partial_ = false;
reader_.UnmarkEOF();
reader_->UnmarkEOF();
}
bool IsEOF() {
return reader_.IsEOF();
}
bool IsEOF() { return reader_->IsEOF(); }
// Returns OK iff recorded error message contains "msg"
std::string MatchError(const std::string& msg) const {
@ -258,23 +264,8 @@ class LogTest : public ::testing::TestWithParam<int> {
return "OK";
}
}
void WriteInitialOffsetLog() {
for (int i = 0; i < 4; i++) {
std::string record(initial_offset_record_sizes_[i],
static_cast<char>('a' + i));
Write(record);
}
}
};
size_t LogTest::initial_offset_record_sizes_[] =
{10000, // Two sizable records in first block
10000,
2 * log::kBlockSize - 1000, // Span three blocks
1};
TEST_P(LogTest, Empty) { ASSERT_EQ("EOF", Read()); }
TEST_P(LogTest, ReadWrite) {
@ -312,7 +303,8 @@ TEST_P(LogTest, Fragmentation) {
TEST_P(LogTest, MarginalTrailer) {
// Make a trailer that is exactly the same length as an empty record.
int header_size = GetParam() ? kRecyclableHeaderSize : kHeaderSize;
int header_size =
std::get<0>(GetParam()) ? kRecyclableHeaderSize : kHeaderSize;
const int n = kBlockSize - 2 * header_size;
Write(BigString("foo", n));
ASSERT_EQ((unsigned int)(kBlockSize - header_size), WrittenBytes());
@ -326,7 +318,8 @@ TEST_P(LogTest, MarginalTrailer) {
TEST_P(LogTest, MarginalTrailer2) {
// Make a trailer that is exactly the same length as an empty record.
int header_size = GetParam() ? kRecyclableHeaderSize : kHeaderSize;
int header_size =
std::get<0>(GetParam()) ? kRecyclableHeaderSize : kHeaderSize;
const int n = kBlockSize - 2 * header_size;
Write(BigString("foo", n));
ASSERT_EQ((unsigned int)(kBlockSize - header_size), WrittenBytes());
@ -339,7 +332,8 @@ TEST_P(LogTest, MarginalTrailer2) {
}
TEST_P(LogTest, ShortTrailer) {
int header_size = GetParam() ? kRecyclableHeaderSize : kHeaderSize;
int header_size =
std::get<0>(GetParam()) ? kRecyclableHeaderSize : kHeaderSize;
const int n = kBlockSize - 2 * header_size + 4;
Write(BigString("foo", n));
ASSERT_EQ((unsigned int)(kBlockSize - header_size + 4), WrittenBytes());
@ -352,7 +346,8 @@ TEST_P(LogTest, ShortTrailer) {
}
TEST_P(LogTest, AlignedEof) {
int header_size = GetParam() ? kRecyclableHeaderSize : kHeaderSize;
int header_size =
std::get<0>(GetParam()) ? kRecyclableHeaderSize : kHeaderSize;
const int n = kBlockSize - 2 * header_size + 4;
Write(BigString("foo", n));
ASSERT_EQ((unsigned int)(kBlockSize - header_size + 4), WrittenBytes());
@ -403,6 +398,11 @@ TEST_P(LogTest, TruncatedTrailingRecordIsIgnored) {
}
TEST_P(LogTest, TruncatedTrailingRecordIsNotIgnored) {
if (allow_retry_read_) {
// If read retry is allowed, then truncated trailing record should not
// raise an error.
return;
}
Write("foo");
ShrinkSize(4); // Drop all payload as well as a header byte
ASSERT_EQ("EOF", Read(WALRecoveryMode::kAbsoluteConsistency));
@ -412,13 +412,20 @@ TEST_P(LogTest, TruncatedTrailingRecordIsNotIgnored) {
}
TEST_P(LogTest, BadLength) {
int header_size = GetParam() ? kRecyclableHeaderSize : kHeaderSize;
if (allow_retry_read_) {
// If read retry is allowed, then we should not raise an error when the
// record length specified in header is longer than data currently
// available. It's possible that the body of the record is not written yet.
return;
}
bool recyclable_log = (std::get<0>(GetParam()) != 0);
int header_size = recyclable_log ? kRecyclableHeaderSize : kHeaderSize;
const int kPayloadSize = kBlockSize - header_size;
Write(BigString("bar", kPayloadSize));
Write("foo");
// Least significant size byte is stored in header[4].
IncrementByte(4, 1);
if (!GetParam()) {
if (!recyclable_log) {
ASSERT_EQ("foo", Read());
ASSERT_EQ(kBlockSize, DroppedBytes());
ASSERT_EQ("OK", MatchError("bad record length"));
@ -428,6 +435,12 @@ TEST_P(LogTest, BadLength) {
}
TEST_P(LogTest, BadLengthAtEndIsIgnored) {
if (allow_retry_read_) {
// If read retry is allowed, then we should not raise an error when the
// record length specified in header is longer than data currently
// available. It's possible that the body of the record is not written yet.
return;
}
Write("foo");
ShrinkSize(1);
ASSERT_EQ("EOF", Read());
@ -436,6 +449,12 @@ TEST_P(LogTest, BadLengthAtEndIsIgnored) {
}
TEST_P(LogTest, BadLengthAtEndIsNotIgnored) {
if (allow_retry_read_) {
// If read retry is allowed, then we should not raise an error when the
// record length specified in header is longer than data currently
// available. It's possible that the body of the record is not written yet.
return;
}
Write("foo");
ShrinkSize(1);
ASSERT_EQ("EOF", Read(WALRecoveryMode::kAbsoluteConsistency));
@ -447,7 +466,8 @@ TEST_P(LogTest, ChecksumMismatch) {
Write("foooooo");
IncrementByte(0, 14);
ASSERT_EQ("EOF", Read());
if (!GetParam()) {
bool recyclable_log = (std::get<0>(GetParam()) != 0);
if (!recyclable_log) {
ASSERT_EQ(14U, DroppedBytes());
ASSERT_EQ("OK", MatchError("checksum mismatch"));
} else {
@ -458,8 +478,10 @@ TEST_P(LogTest, ChecksumMismatch) {
TEST_P(LogTest, UnexpectedMiddleType) {
Write("foo");
SetByte(6, static_cast<char>(GetParam() ? kRecyclableMiddleType : kMiddleType));
FixChecksum(0, 3, !!GetParam());
bool recyclable_log = (std::get<0>(GetParam()) != 0);
SetByte(6, static_cast<char>(recyclable_log ? kRecyclableMiddleType
: kMiddleType));
FixChecksum(0, 3, !!recyclable_log);
ASSERT_EQ("EOF", Read());
ASSERT_EQ(3U, DroppedBytes());
ASSERT_EQ("OK", MatchError("missing start"));
@ -467,8 +489,10 @@ TEST_P(LogTest, UnexpectedMiddleType) {
TEST_P(LogTest, UnexpectedLastType) {
Write("foo");
SetByte(6, static_cast<char>(GetParam() ? kRecyclableLastType : kLastType));
FixChecksum(0, 3, !!GetParam());
bool recyclable_log = (std::get<0>(GetParam()) != 0);
SetByte(6,
static_cast<char>(recyclable_log ? kRecyclableLastType : kLastType));
FixChecksum(0, 3, !!recyclable_log);
ASSERT_EQ("EOF", Read());
ASSERT_EQ(3U, DroppedBytes());
ASSERT_EQ("OK", MatchError("missing start"));
@ -477,8 +501,10 @@ TEST_P(LogTest, UnexpectedLastType) {
TEST_P(LogTest, UnexpectedFullType) {
Write("foo");
Write("bar");
SetByte(6, static_cast<char>(GetParam() ? kRecyclableFirstType : kFirstType));
FixChecksum(0, 3, !!GetParam());
bool recyclable_log = (std::get<0>(GetParam()) != 0);
SetByte(
6, static_cast<char>(recyclable_log ? kRecyclableFirstType : kFirstType));
FixChecksum(0, 3, !!recyclable_log);
ASSERT_EQ("bar", Read());
ASSERT_EQ("EOF", Read());
ASSERT_EQ(3U, DroppedBytes());
@ -488,8 +514,10 @@ TEST_P(LogTest, UnexpectedFullType) {
TEST_P(LogTest, UnexpectedFirstType) {
Write("foo");
Write(BigString("bar", 100000));
SetByte(6, static_cast<char>(GetParam() ? kRecyclableFirstType : kFirstType));
FixChecksum(0, 3, !!GetParam());
bool recyclable_log = (std::get<0>(GetParam()) != 0);
SetByte(
6, static_cast<char>(recyclable_log ? kRecyclableFirstType : kFirstType));
FixChecksum(0, 3, !!recyclable_log);
ASSERT_EQ(BigString("bar", 100000), Read());
ASSERT_EQ("EOF", Read());
ASSERT_EQ(3U, DroppedBytes());
@ -506,6 +534,11 @@ TEST_P(LogTest, MissingLastIsIgnored) {
}
TEST_P(LogTest, MissingLastIsNotIgnored) {
if (allow_retry_read_) {
// If read retry is allowed, then truncated trailing record should not
// raise an error.
return;
}
Write(BigString("bar", kBlockSize));
// Remove the LAST block, including header.
ShrinkSize(14);
@ -524,6 +557,11 @@ TEST_P(LogTest, PartialLastIsIgnored) {
}
TEST_P(LogTest, PartialLastIsNotIgnored) {
if (allow_retry_read_) {
// If read retry is allowed, then truncated trailing record should not
// raise an error.
return;
}
Write(BigString("bar", kBlockSize));
// Cause a bad record length in the LAST block.
ShrinkSize(1);
@ -550,7 +588,8 @@ TEST_P(LogTest, ErrorJoinsRecords) {
SetByte(offset, 'x');
}
if (!GetParam()) {
bool recyclable_log = (std::get<0>(GetParam()) != 0);
if (!recyclable_log) {
ASSERT_EQ("correct", Read());
ASSERT_EQ("EOF", Read());
size_t dropped = DroppedBytes();
@ -564,7 +603,8 @@ TEST_P(LogTest, ErrorJoinsRecords) {
TEST_P(LogTest, ClearEofSingleBlock) {
Write("foo");
Write("bar");
int header_size = GetParam() ? kRecyclableHeaderSize : kHeaderSize;
bool recyclable_log = (std::get<0>(GetParam()) != 0);
int header_size = recyclable_log ? kRecyclableHeaderSize : kHeaderSize;
ForceEOF(3 + header_size + 2);
ASSERT_EQ("foo", Read());
UnmarkEOF();
@ -579,7 +619,8 @@ TEST_P(LogTest, ClearEofSingleBlock) {
TEST_P(LogTest, ClearEofMultiBlock) {
size_t num_full_blocks = 5;
int header_size = GetParam() ? kRecyclableHeaderSize : kHeaderSize;
bool recyclable_log = (std::get<0>(GetParam()) != 0);
int header_size = recyclable_log ? kRecyclableHeaderSize : kHeaderSize;
size_t n = (kBlockSize - header_size) * num_full_blocks + 25;
Write(BigString("foo", n));
Write(BigString("bar", n));
@ -628,7 +669,8 @@ TEST_P(LogTest, ClearEofError2) {
}
TEST_P(LogTest, Recycle) {
if (!GetParam()) {
bool recyclable_log = (std::get<0>(GetParam()) != 0);
if (!recyclable_log) {
return; // test is only valid for recycled logs
}
Write("foo");
@ -651,7 +693,11 @@ TEST_P(LogTest, Recycle) {
ASSERT_EQ("EOF", Read());
}
INSTANTIATE_TEST_CASE_P(bool, LogTest, ::testing::Values(0, 2));
INSTANTIATE_TEST_CASE_P(bool, LogTest,
::testing::Values(std::make_tuple(0, false),
std::make_tuple(0, true),
std::make_tuple(1, false),
std::make_tuple(1, true)));
class RetriableLogTest : public ::testing::TestWithParam<int> {
private:
@ -677,7 +723,7 @@ class RetriableLogTest : public ::testing::TestWithParam<int> {
std::unique_ptr<WritableFileWriter> writer_;
std::unique_ptr<SequentialFileReader> reader_;
ReportCollector report_;
std::unique_ptr<Reader> log_reader_;
std::unique_ptr<FragmentBufferedReader> log_reader_;
public:
RetriableLogTest()
@ -716,9 +762,9 @@ class RetriableLogTest : public ::testing::TestWithParam<int> {
if (s.ok()) {
reader_.reset(new SequentialFileReader(std::move(seq_file), log_file_));
assert(reader_ != nullptr);
log_reader_.reset(new Reader(nullptr, std::move(reader_), &report_,
true /* checksum */, 123 /* log_number */,
true /* retry_after_eof */));
log_reader_.reset(new FragmentBufferedReader(
nullptr, std::move(reader_), &report_, true /* checksum */,
123 /* log_number */));
assert(log_reader_ != nullptr);
}
return s;
@ -738,14 +784,17 @@ class RetriableLogTest : public ::testing::TestWithParam<int> {
writer_->Sync(true);
}
std::string Read() {
auto wal_recovery_mode = WALRecoveryMode::kTolerateCorruptedTailRecords;
bool TryRead(std::string* result) {
assert(result != nullptr);
result->clear();
std::string scratch;
Slice record;
if (log_reader_->ReadRecord(&record, &scratch, wal_recovery_mode)) {
return record.ToString();
bool r = log_reader_->ReadRecord(&record, &scratch);
if (r) {
result->assign(record.data(), record.size());
return true;
} else {
return "Read error";
return false;
}
}
};
@ -754,12 +803,17 @@ TEST_P(RetriableLogTest, TailLog_PartialHeader) {
ASSERT_OK(SetupTestEnv());
std::vector<int> remaining_bytes_in_last_record;
size_t header_size = GetParam() ? kRecyclableHeaderSize : kHeaderSize;
bool eof = false;
SyncPoint::GetInstance()->DisableProcessing();
SyncPoint::GetInstance()->LoadDependency(
{{"RetriableLogTest::TailLog:AfterPart1",
"RetriableLogTest::TailLog:BeforeReadRecord"},
{"LogReader::ReadMore:FirstEOF",
{"FragmentBufferedLogReader::TryReadMore:FirstEOF",
"RetriableLogTest::TailLog:BeforePart2"}});
SyncPoint::GetInstance()->ClearAllCallBacks();
SyncPoint::GetInstance()->SetCallBack(
"FragmentBufferedLogReader::TryReadMore:FirstEOF",
[&](void* /*arg*/) { eof = true; });
SyncPoint::GetInstance()->EnableProcessing();
size_t delta = header_size - 1;
@ -779,23 +833,30 @@ TEST_P(RetriableLogTest, TailLog_PartialHeader) {
std::string record;
port::Thread log_reader_thread([&]() {
TEST_SYNC_POINT("RetriableLogTest::TailLog:BeforeReadRecord");
record = Read();
while (!TryRead(&record)) {
}
});
log_reader_thread.join();
log_writer_thread.join();
ASSERT_EQ("foo", record);
ASSERT_TRUE(eof);
}
TEST_P(RetriableLogTest, TailLog_FullHeader) {
ASSERT_OK(SetupTestEnv());
std::vector<int> remaining_bytes_in_last_record;
size_t header_size = GetParam() ? kRecyclableHeaderSize : kHeaderSize;
bool eof = false;
SyncPoint::GetInstance()->DisableProcessing();
SyncPoint::GetInstance()->LoadDependency(
{{"RetriableLogTest::TailLog:AfterPart1",
"RetriableLogTest::TailLog:BeforeReadRecord"},
{"LogReader::ReadMore:FirstEOF",
{"FragmentBufferedLogReader::TryReadMore:FirstEOF",
"RetriableLogTest::TailLog:BeforePart2"}});
SyncPoint::GetInstance()->ClearAllCallBacks();
SyncPoint::GetInstance()->SetCallBack(
"FragmentBufferedLogReader::TryReadMore:FirstEOF",
[&](void* /*arg*/) { eof = true; });
SyncPoint::GetInstance()->EnableProcessing();
size_t delta = header_size + 1;
@ -810,18 +871,45 @@ TEST_P(RetriableLogTest, TailLog_FullHeader) {
TEST_SYNC_POINT("RetriableLogTest::TailLog:AfterPart1");
TEST_SYNC_POINT("RetriableLogTest::TailLog:BeforePart2");
Write(Slice(part2));
ASSERT_TRUE(eof);
});
std::string record;
port::Thread log_reader_thread([&]() {
TEST_SYNC_POINT("RetriableLogTest::TailLog:BeforeReadRecord");
record = Read();
while (!TryRead(&record)) {
}
});
log_reader_thread.join();
log_writer_thread.join();
ASSERT_EQ("foo", record);
}
TEST_P(RetriableLogTest, NonBlockingReadFullRecord) {
// Clear all sync point callbacks even if this test does not use sync point.
// It is necessary, otherwise the execute of this test may hit a sync point
// with which a callback is registered. The registered callback may access
// some dead variable, causing segfault.
SyncPoint::GetInstance()->DisableProcessing();
SyncPoint::GetInstance()->ClearAllCallBacks();
ASSERT_OK(SetupTestEnv());
size_t header_size = GetParam() ? kRecyclableHeaderSize : kHeaderSize;
size_t delta = header_size - 1;
size_t old_sz = contents().size();
Encode("foo-bar");
size_t new_sz = contents().size();
std::string part1 = contents().substr(old_sz, delta);
std::string part2 =
contents().substr(old_sz + delta, new_sz - old_sz - delta);
Write(Slice(part1));
std::string record;
ASSERT_FALSE(TryRead(&record));
ASSERT_TRUE(record.empty());
Write(Slice(part2));
ASSERT_TRUE(TryRead(&record));
ASSERT_EQ("foo-bar", record);
}
INSTANTIATE_TEST_CASE_P(bool, RetriableLogTest, ::testing::Values(0, 2));
} // namespace log

3
db/repair.cc
View File

@ -364,8 +364,7 @@ class Repairer {
// propagating bad information (like overly large sequence
// numbers).
log::Reader reader(db_options_.info_log, std::move(lfile_reader), &reporter,
true /*enable checksum*/, log,
false /* retry_after_eof */);
true /*enable checksum*/, log);
// Initialize per-column family memtables
for (auto* cfd : *vset_.GetColumnFamilySet()) {

3
db/transaction_log_impl.cc
View File

@ -315,8 +315,7 @@ Status TransactionLogIteratorImpl::OpenLogReader(const LogFile* logFile) {
assert(file);
currentLogReader_.reset(
new log::Reader(options_->info_log, std::move(file), &reporter_,
read_options_.verify_checksums_, logFile->LogNumber(),
false /* retry_after_eof */));
read_options_.verify_checksums_, logFile->LogNumber()));
return Status::OK();
}
} // namespace rocksdb

42
db/version_builder.cc
View File

@ -364,10 +364,10 @@ class VersionBuilder::Rep {
CheckConsistency(vstorage);
}
void LoadTableHandlers(InternalStats* internal_stats, int max_threads,
bool prefetch_index_and_filter_in_cache,
bool is_initial_load,
const SliceTransform* prefix_extractor) {
Status LoadTableHandlers(InternalStats* internal_stats, int max_threads,
bool prefetch_index_and_filter_in_cache,
bool is_initial_load,
const SliceTransform* prefix_extractor) {
assert(table_cache_ != nullptr);
size_t table_cache_capacity = table_cache_->get_cache()->GetCapacity();
@ -394,7 +394,8 @@ class VersionBuilder::Rep {
size_t table_cache_usage = table_cache_->get_cache()->GetUsage();
if (table_cache_usage >= load_limit) {
return;
// TODO (yanqin) find a suitable status code.
return Status::OK();
} else {
max_load = load_limit - table_cache_usage;
}
@ -402,11 +403,15 @@ class VersionBuilder::Rep {
// <file metadata, level>
std::vector<std::pair<FileMetaData*, int>> files_meta;
std::vector<Status> statuses;
for (int level = 0; level < num_levels_; level++) {
for (auto& file_meta_pair : levels_[level].added_files) {
auto* file_meta = file_meta_pair.second;
assert(!file_meta->table_reader_handle);
files_meta.emplace_back(file_meta, level);
// If the file has been opened before, just skip it.
if (!file_meta->table_reader_handle) {
files_meta.emplace_back(file_meta, level);
statuses.emplace_back(Status::OK());
}
if (files_meta.size() >= max_load) {
break;
}
@ -426,7 +431,7 @@ class VersionBuilder::Rep {
auto* file_meta = files_meta[file_idx].first;
int level = files_meta[file_idx].second;
table_cache_->FindTable(
statuses[file_idx] = table_cache_->FindTable(
env_options_, *(base_vstorage_->InternalComparator()),
file_meta->fd, &file_meta->table_reader_handle, prefix_extractor,
false /*no_io */, true /* record_read_stats */,
@ -448,6 +453,12 @@ class VersionBuilder::Rep {
for (auto& t : threads) {
t.join();
}
for (const auto& s : statuses) {
if (!s.ok()) {
return s;
}
}
return Status::OK();
}
void MaybeAddFile(VersionStorageInfo* vstorage, int level, FileMetaData* f) {
@ -487,14 +498,13 @@ void VersionBuilder::SaveTo(VersionStorageInfo* vstorage) {
rep_->SaveTo(vstorage);
}
void VersionBuilder::LoadTableHandlers(InternalStats* internal_stats,
int max_threads,
bool prefetch_index_and_filter_in_cache,
bool is_initial_load,
const SliceTransform* prefix_extractor) {
rep_->LoadTableHandlers(internal_stats, max_threads,
prefetch_index_and_filter_in_cache, is_initial_load,
prefix_extractor);
Status VersionBuilder::LoadTableHandlers(
InternalStats* internal_stats, int max_threads,
bool prefetch_index_and_filter_in_cache, bool is_initial_load,
const SliceTransform* prefix_extractor) {
return rep_->LoadTableHandlers(internal_stats, max_threads,
prefetch_index_and_filter_in_cache,
is_initial_load, prefix_extractor);
}
void VersionBuilder::MaybeAddFile(VersionStorageInfo* vstorage, int level,

8
db/version_builder.h
View File

@ -33,10 +33,10 @@ class VersionBuilder {
bool CheckConsistencyForNumLevels();
void Apply(VersionEdit* edit);
void SaveTo(VersionStorageInfo* vstorage);
void LoadTableHandlers(InternalStats* internal_stats, int max_threads,
bool prefetch_index_and_filter_in_cache,
bool is_initial_load,
const SliceTransform* prefix_extractor);
Status LoadTableHandlers(InternalStats* internal_stats, int max_threads,
bool prefetch_index_and_filter_in_cache,
bool is_initial_load,
const SliceTransform* prefix_extractor);
void MaybeAddFile(VersionStorageInfo* vstorage, int level, FileMetaData* f);
private:

1
db/version_edit.h
View File

@ -313,6 +313,7 @@ class VersionEdit {
std::string DebugJSON(int edit_num, bool hex_key = false) const;
private:
friend class ReactiveVersionSet;
friend class VersionSet;
friend class Version;

548
db/version_set.cc
View File

@ -712,6 +712,7 @@ void LevelIterator::InitFileIterator(size_t new_file_index) {
}
}
}
} // anonymous namespace
// A wrapper of version builder which references the current version in
// constructor and unref it in the destructor.
@ -726,16 +727,14 @@ class BaseReferencedVersionBuilder {
version_->Ref();
}
~BaseReferencedVersionBuilder() {
delete version_builder_;
version_->Unref();
}
VersionBuilder* version_builder() { return version_builder_; }
VersionBuilder* version_builder() { return version_builder_.get(); }
private:
VersionBuilder* version_builder_;
std::unique_ptr<VersionBuilder> version_builder_;
Version* version_;
};
} // anonymous namespace
Status Version::GetTableProperties(std::shared_ptr<const TableProperties>* tp,
const FileMetaData* file_meta,
@ -2936,7 +2935,7 @@ Status VersionSet::ProcessManifestWrites(
} else if (group_start != std::numeric_limits<size_t>::max()) {
group_start = std::numeric_limits<size_t>::max();
}
LogAndApplyHelper(last_writer->cfd, builder, version, e, mu);
LogAndApplyHelper(last_writer->cfd, builder, e, mu);
batch_edits.push_back(e);
}
}
@ -2990,6 +2989,7 @@ Status VersionSet::ProcessManifestWrites(
assert(pending_manifest_file_number_ == 0);
if (!descriptor_log_ ||
manifest_file_size_ > db_options_->max_manifest_file_size) {
TEST_SYNC_POINT("VersionSet::ProcessManifestWrites:BeforeNewManifest");
pending_manifest_file_number_ = NewFileNumber();
batch_edits.back()->SetNextFile(next_file_number_.load());
new_descriptor_log = true;
@ -3098,6 +3098,7 @@ Status VersionSet::ProcessManifestWrites(
if (s.ok() && new_descriptor_log) {
s = SetCurrentFile(env_, dbname_, pending_manifest_file_number_,
db_directory);
TEST_SYNC_POINT("VersionSet::ProcessManifestWrites:AfterNewManifest");
}
if (s.ok()) {
@ -3225,7 +3226,7 @@ Status VersionSet::ProcessManifestWrites(
return s;
}
// 'datas' is gramatically incorrect. We still use this notation is to indicate
// 'datas' is gramatically incorrect. We still use this notation to indicate
// that this variable represents a collection of column_family_data.
Status VersionSet::LogAndApply(
const autovector<ColumnFamilyData*>& column_family_datas,
@ -3325,8 +3326,8 @@ void VersionSet::LogAndApplyCFHelper(VersionEdit* edit) {
}
void VersionSet::LogAndApplyHelper(ColumnFamilyData* cfd,
VersionBuilder* builder, Version* /*v*/,
VersionEdit* edit, InstrumentedMutex* mu) {
VersionBuilder* builder, VersionEdit* edit,
InstrumentedMutex* mu) {
#ifdef NDEBUG
(void)cfd;
#endif
@ -3353,16 +3354,16 @@ void VersionSet::LogAndApplyHelper(ColumnFamilyData* cfd,
builder->Apply(edit);
}
Status VersionSet::ApplyOneVersionEdit(
Status VersionSet::ApplyOneVersionEditToBuilder(
VersionEdit& edit,
const std::unordered_map<std::string, ColumnFamilyOptions>& name_to_options,
std::unordered_map<int, std::string>& column_families_not_found,
std::unordered_map<uint32_t, BaseReferencedVersionBuilder*>& builders,
bool* have_log_number, uint64_t* /* log_number */,
bool* have_prev_log_number, uint64_t* previous_log_number,
bool* have_next_file, uint64_t* next_file, bool* have_last_sequence,
SequenceNumber* last_sequence, uint64_t* min_log_number_to_keep,
uint32_t* max_column_family) {
std::unordered_map<uint32_t, std::unique_ptr<BaseReferencedVersionBuilder>>&
builders,
bool* have_log_number, uint64_t* log_number, bool* have_prev_log_number,
uint64_t* previous_log_number, bool* have_next_file, uint64_t* next_file,
bool* have_last_sequence, SequenceNumber* last_sequence,
uint64_t* min_log_number_to_keep, uint32_t* max_column_family) {
// Not found means that user didn't supply that column
// family option AND we encountered column family add
// record. Once we encounter column family drop record,
@ -3392,14 +3393,14 @@ Status VersionSet::ApplyOneVersionEdit(
} else {
cfd = CreateColumnFamily(cf_options->second, &edit);
cfd->set_initialized();
builders.insert(
{edit.column_family_, new BaseReferencedVersionBuilder(cfd)});
builders.insert(std::make_pair(
edit.column_family_, std::unique_ptr<BaseReferencedVersionBuilder>(
new BaseReferencedVersionBuilder(cfd))));
}
} else if (edit.is_column_family_drop_) {
if (cf_in_builders) {
auto builder = builders.find(edit.column_family_);
assert(builder != builders.end());
delete builder->second;
builders.erase(builder);
cfd = column_family_set_->GetColumnFamily(edit.column_family_);
assert(cfd != nullptr);
@ -3433,7 +3434,18 @@ Status VersionSet::ApplyOneVersionEdit(
assert(builder != builders.end());
builder->second->version_builder()->Apply(&edit);
}
return ExtractInfoFromVersionEdit(
cfd, edit, have_log_number, log_number, have_prev_log_number,
previous_log_number, have_next_file, next_file, have_last_sequence,
last_sequence, min_log_number_to_keep, max_column_family);
}
Status VersionSet::ExtractInfoFromVersionEdit(
ColumnFamilyData* cfd, const VersionEdit& edit, bool* have_log_number,
uint64_t* log_number, bool* have_prev_log_number,
uint64_t* previous_log_number, bool* have_next_file, uint64_t* next_file,
bool* have_last_sequence, SequenceNumber* last_sequence,
uint64_t* min_log_number_to_keep, uint32_t* max_column_family) {
if (cfd != nullptr) {
if (edit.has_log_number_) {
if (cfd->GetLogNumber() > edit.log_number_) {
@ -3444,6 +3456,7 @@ Status VersionSet::ApplyOneVersionEdit(
} else {
cfd->SetLogNumber(edit.log_number_);
*have_log_number = true;
*log_number = edit.log_number_;
}
}
if (edit.has_comparator_ &&
@ -3480,6 +3493,31 @@ Status VersionSet::ApplyOneVersionEdit(
return Status::OK();
}
Status VersionSet::GetCurrentManifestPath(std::string* manifest_path) {
assert(manifest_path != nullptr);
std::string fname;
Status s = ReadFileToString(env_, CurrentFileName(dbname_), &fname);
if (!s.ok()) {
return s;
}
if (fname.empty() || fname.back() != '\n') {
return Status::Corruption("CURRENT file does not end with newline");
}
// remove the trailing '\n'
fname.resize(fname.size() - 1);
FileType type;
bool parse_ok = ParseFileName(fname, &manifest_file_number_, &type);
if (!parse_ok || type != kDescriptorFile) {
return Status::Corruption("CURRENT file corrupted");
}
*manifest_path = dbname_;
if (dbname_.back() != '/') {
manifest_path->push_back('/');
}
*manifest_path += fname;
return Status::OK();
}
Status VersionSet::Recover(
const std::vector<ColumnFamilyDescriptor>& column_families,
bool read_only) {
@ -3493,43 +3531,28 @@ Status VersionSet::Recover(
std::unordered_map<int, std::string> column_families_not_found;
// Read "CURRENT" file, which contains a pointer to the current manifest file
std::string manifest_filename;
Status s = ReadFileToString(
env_, CurrentFileName(dbname_), &manifest_filename
);
std::string manifest_path;
Status s = GetCurrentManifestPath(&manifest_path);
if (!s.ok()) {
return s;
}
if (manifest_filename.empty() ||
manifest_filename.back() != '\n') {
return Status::Corruption("CURRENT file does not end with newline");
}
// remove the trailing '\n'
manifest_filename.resize(manifest_filename.size() - 1);
FileType type;
bool parse_ok =
ParseFileName(manifest_filename, &manifest_file_number_, &type);
if (!parse_ok || type != kDescriptorFile) {
return Status::Corruption("CURRENT file corrupted");
}
ROCKS_LOG_INFO(db_options_->info_log, "Recovering from manifest file: %s\n",
manifest_filename.c_str());
manifest_path.c_str());
manifest_filename = dbname_ + "/" + manifest_filename;
std::unique_ptr<SequentialFileReader> manifest_file_reader;
{
std::unique_ptr<SequentialFile> manifest_file;
s = env_->NewSequentialFile(manifest_filename, &manifest_file,
s = env_->NewSequentialFile(manifest_path, &manifest_file,
env_->OptimizeForManifestRead(env_options_));
if (!s.ok()) {
return s;
}
manifest_file_reader.reset(
new SequentialFileReader(std::move(manifest_file), manifest_filename));
new SequentialFileReader(std::move(manifest_file), manifest_path));
}
uint64_t current_manifest_file_size;
s = env_->GetFileSize(manifest_filename, &current_manifest_file_size);
s = env_->GetFileSize(manifest_path, &current_manifest_file_size);
if (!s.ok()) {
return s;
}
@ -3544,7 +3567,8 @@ Status VersionSet::Recover(
uint64_t previous_log_number = 0;
uint32_t max_column_family = 0;
uint64_t min_log_number_to_keep = 0;
std::unordered_map<uint32_t, BaseReferencedVersionBuilder*> builders;
std::unordered_map<uint32_t, std::unique_ptr<BaseReferencedVersionBuilder>>
builders;
// add default column family
auto default_cf_iter = cf_name_to_options.find(kDefaultColumnFamilyName);
@ -3559,14 +3583,15 @@ Status VersionSet::Recover(
// In recovery, nobody else can access it, so it's fine to set it to be
// initialized earlier.
default_cfd->set_initialized();
builders.insert({0, new BaseReferencedVersionBuilder(default_cfd)});
builders.insert(
std::make_pair(0, std::unique_ptr<BaseReferencedVersionBuilder>(
new BaseReferencedVersionBuilder(default_cfd))));
{
VersionSet::LogReporter reporter;
reporter.status = &s;
log::Reader reader(nullptr, std::move(manifest_file_reader), &reporter,
true /* checksum */, 0 /* log_number */,
false /* retry_after_eof */);
true /* checksum */, 0 /* log_number */);
Slice record;
std::string scratch;
std::vector<VersionEdit> replay_buffer;
@ -3597,7 +3622,7 @@ Status VersionSet::Recover(
TEST_SYNC_POINT_CALLBACK("VersionSet::Recover:LastInAtomicGroup",
&edit);
for (auto& e : replay_buffer) {
s = ApplyOneVersionEdit(
s = ApplyOneVersionEditToBuilder(
e, cf_name_to_options, column_families_not_found, builders,
&have_log_number, &log_number, &have_prev_log_number,
&previous_log_number, &have_next_file, &next_file,
@ -3618,7 +3643,7 @@ Status VersionSet::Recover(
s = Status::Corruption("corrupted atomic group");
break;
}
s = ApplyOneVersionEdit(
s = ApplyOneVersionEditToBuilder(
edit, cf_name_to_options, column_families_not_found, builders,
&have_log_number, &log_number, &have_prev_log_number,
&previous_log_number, &have_next_file, &next_file,
@ -3689,7 +3714,7 @@ Status VersionSet::Recover(
assert(cfd->initialized());
auto builders_iter = builders.find(cfd->GetID());
assert(builders_iter != builders.end());
auto* builder = builders_iter->second->version_builder();
auto builder = builders_iter->second->version_builder();
// unlimited table cache. Pre-load table handle now.
// Need to do it out of the mutex.
@ -3725,7 +3750,7 @@ Status VersionSet::Recover(
"prev_log_number is %lu,"
"max_column_family is %u,"
"min_log_number_to_keep is %lu\n",
manifest_filename.c_str(), (unsigned long)manifest_file_number_,
manifest_path.c_str(), (unsigned long)manifest_file_number_,
(unsigned long)next_file_number_.load(), (unsigned long)last_sequence_,
(unsigned long)log_number, (unsigned long)prev_log_number_,
column_family_set_->GetMaxColumnFamily(), min_log_number_to_keep_2pc());
@ -3740,10 +3765,6 @@ Status VersionSet::Recover(
}
}
for (auto& builder : builders) {
delete builder.second;
}
return s;
}
@ -3781,8 +3802,7 @@ Status VersionSet::ListColumnFamilies(std::vector<std::string>* column_families,
VersionSet::LogReporter reporter;
reporter.status = &s;
log::Reader reader(nullptr, std::move(file_reader), &reporter,
true /* checksum */, 0 /* log_number */,
false /* retry_after_eof */);
true /* checksum */, 0 /* log_number */);
Slice record;
std::string scratch;
while (reader.ReadRecord(&record, &scratch) && s.ok()) {
@ -3928,7 +3948,8 @@ Status VersionSet::DumpManifest(Options& options, std::string& dscname,
uint64_t previous_log_number = 0;
int count = 0;
std::unordered_map<uint32_t, std::string> comparators;
std::unordered_map<uint32_t, BaseReferencedVersionBuilder*> builders;
std::unordered_map<uint32_t, std::unique_ptr<BaseReferencedVersionBuilder>>
builders;
// add default column family
VersionEdit default_cf_edit;
@ -3936,14 +3957,15 @@ Status VersionSet::DumpManifest(Options& options, std::string& dscname,
default_cf_edit.SetColumnFamily(0);
ColumnFamilyData* default_cfd =
CreateColumnFamily(ColumnFamilyOptions(options), &default_cf_edit);
builders.insert({0, new BaseReferencedVersionBuilder(default_cfd)});
builders.insert(
std::make_pair(0, std::unique_ptr<BaseReferencedVersionBuilder>(
new BaseReferencedVersionBuilder(default_cfd))));
{
VersionSet::LogReporter reporter;
reporter.status = &s;
log::Reader reader(nullptr, std::move(file_reader), &reporter,
true /* checksum */, 0 /* log_number */,
false /* retry_after_eof */);
true /* checksum */, 0 /* log_number */);
Slice record;
std::string scratch;
while (reader.ReadRecord(&record, &scratch) && s.ok()) {
@ -3978,8 +4000,9 @@ Status VersionSet::DumpManifest(Options& options, std::string& dscname,
}
cfd = CreateColumnFamily(ColumnFamilyOptions(options), &edit);
cfd->set_initialized();
builders.insert(
{edit.column_family_, new BaseReferencedVersionBuilder(cfd)});
builders.insert(std::make_pair(
edit.column_family_, std::unique_ptr<BaseReferencedVersionBuilder>(
new BaseReferencedVersionBuilder(cfd))));
} else if (edit.is_column_family_drop_) {
if (!cf_in_builders) {
s = Status::Corruption(
@ -3987,7 +4010,6 @@ Status VersionSet::DumpManifest(Options& options, std::string& dscname,
break;
}
auto builder_iter = builders.find(edit.column_family_);
delete builder_iter->second;
builders.erase(builder_iter);
comparators.erase(edit.column_family_);
cfd = column_family_set_->GetColumnFamily(edit.column_family_);
@ -4087,11 +4109,6 @@ Status VersionSet::DumpManifest(Options& options, std::string& dscname,
delete v;
}
// Free builders
for (auto& builder : builders) {
delete builder.second;
}
next_file_number_.store(next_file + 1);
last_allocated_sequence_ = last_sequence;
last_published_sequence_ = last_sequence;
@ -4583,4 +4600,405 @@ uint64_t VersionSet::GetTotalSstFilesSize(Version* dummy_versions) {
return total_files_size;
}
ReactiveVersionSet::ReactiveVersionSet(const std::string& dbname,
const ImmutableDBOptions* _db_options,
const EnvOptions& _env_options,
Cache* table_cache,
WriteBufferManager* write_buffer_manager,
WriteController* write_controller)
: VersionSet(dbname, _db_options, _env_options, table_cache,
write_buffer_manager, write_controller) {}
ReactiveVersionSet::~ReactiveVersionSet() {}
Status ReactiveVersionSet::Recover(
const std::vector<ColumnFamilyDescriptor>& column_families,
std::unique_ptr<log::FragmentBufferedReader>* manifest_reader,
std::unique_ptr<log::Reader::Reporter>* manifest_reporter,
std::unique_ptr<Status>* manifest_reader_status) {
assert(manifest_reader != nullptr);
assert(manifest_reporter != nullptr);
assert(manifest_reader_status != nullptr);
std::unordered_map<std::string, ColumnFamilyOptions> cf_name_to_options;
for (const auto& cf : column_families) {
cf_name_to_options.insert({cf.name, cf.options});
}
// add default column family
auto default_cf_iter = cf_name_to_options.find(kDefaultColumnFamilyName);
if (default_cf_iter == cf_name_to_options.end()) {
return Status::InvalidArgument("Default column family not specified");
}
VersionEdit default_cf_edit;
default_cf_edit.AddColumnFamily(kDefaultColumnFamilyName);
default_cf_edit.SetColumnFamily(0);
ColumnFamilyData* default_cfd =
CreateColumnFamily(default_cf_iter->second, &default_cf_edit);
// In recovery, nobody else can access it, so it's fine to set it to be
// initialized earlier.
default_cfd->set_initialized();
bool have_log_number = false;
bool have_prev_log_number = false;
bool have_next_file = false;
bool have_last_sequence = false;
uint64_t next_file = 0;
uint64_t last_sequence = 0;
uint64_t log_number = 0;
uint64_t previous_log_number = 0;
uint32_t max_column_family = 0;
uint64_t min_log_number_to_keep = 0;
std::unordered_map<uint32_t, std::unique_ptr<BaseReferencedVersionBuilder>>
builders;
std::unordered_map<int, std::string> column_families_not_found;
builders.insert(
std::make_pair(0, std::unique_ptr<BaseReferencedVersionBuilder>(
new BaseReferencedVersionBuilder(default_cfd))));
manifest_reader_status->reset(new Status());
manifest_reporter->reset(new LogReporter());
static_cast<LogReporter*>(manifest_reporter->get())->status =
manifest_reader_status->get();
Status s = MaybeSwitchManifest(manifest_reporter->get(), manifest_reader);
log::Reader* reader = manifest_reader->get();
int retry = 0;
while (s.ok() && retry < 1) {
assert(reader != nullptr);
Slice record;
std::string scratch;
while (s.ok() && reader->ReadRecord(&record, &scratch)) {
VersionEdit edit;
s = edit.DecodeFrom(record);
if (!s.ok()) {
break;
}
s = ApplyOneVersionEditToBuilder(
edit, cf_name_to_options, column_families_not_found, builders,
&have_log_number, &log_number, &have_prev_log_number,
&previous_log_number, &have_next_file, &next_file,
&have_last_sequence, &last_sequence, &min_log_number_to_keep,
&max_column_family);
}
if (s.ok()) {
bool enough = have_next_file && have_log_number && have_last_sequence;
if (enough) {
for (const auto& cf : column_families) {
auto cfd = column_family_set_->GetColumnFamily(cf.name);
if (cfd == nullptr) {
enough = false;
break;
}
}
}
if (enough) {
for (const auto& cf : column_families) {
auto cfd = column_family_set_->GetColumnFamily(cf.name);
assert(cfd != nullptr);
if (!cfd->IsDropped()) {
auto builder_iter = builders.find(cfd->GetID());
assert(builder_iter != builders.end());
auto builder = builder_iter->second->version_builder();
assert(builder != nullptr);
s = builder->LoadTableHandlers(
cfd->internal_stats(), db_options_->max_file_opening_threads,
false /* prefetch_index_and_filter_in_cache */,
true /* is_initial_load */,
cfd->GetLatestMutableCFOptions()->prefix_extractor.get());
if (!s.ok()) {
enough = false;
if (s.IsPathNotFound()) {
s = Status::OK();
}
break;
}
}
}
}
if (enough) {
break;
}
}
++retry;
}
if (s.ok()) {
if (!have_prev_log_number) {
previous_log_number = 0;
}
column_family_set_->UpdateMaxColumnFamily(max_column_family);
MarkMinLogNumberToKeep2PC(min_log_number_to_keep);
MarkFileNumberUsed(previous_log_number);
MarkFileNumberUsed(log_number);
for (auto cfd : *column_family_set_) {
assert(builders.count(cfd->GetID()) > 0);
auto builder = builders[cfd->GetID()]->version_builder();
if (!builder->CheckConsistencyForNumLevels()) {
s = Status::InvalidArgument(
"db has more levels than options.num_levels");
break;
}
}
}
if (s.ok()) {
for (auto cfd : *column_family_set_) {
if (cfd->IsDropped()) {
continue;
}
assert(cfd->initialized());
auto builders_iter = builders.find(cfd->GetID());
assert(builders_iter != builders.end());
auto* builder = builders_iter->second->version_builder();
Version* v = new Version(cfd, this, env_options_,
*cfd->GetLatestMutableCFOptions(),
current_version_number_++);
builder->SaveTo(v->storage_info());
// Install recovered version
v->PrepareApply(*cfd->GetLatestMutableCFOptions(),
!(db_options_->skip_stats_update_on_db_open));
AppendVersion(cfd, v);
}
next_file_number_.store(next_file + 1);
last_allocated_sequence_ = last_sequence;
last_published_sequence_ = last_sequence;
last_sequence_ = last_sequence;
prev_log_number_ = previous_log_number;
for (auto cfd : *column_family_set_) {
if (cfd->IsDropped()) {
continue;
}
ROCKS_LOG_INFO(db_options_->info_log,
"Column family [%s] (ID %u), log number is %" PRIu64 "\n",
cfd->GetName().c_str(), cfd->GetID(), cfd->GetLogNumber());
}
}
return s;
}
Status ReactiveVersionSet::ReadAndApply(
InstrumentedMutex* mu,
std::unique_ptr<log::FragmentBufferedReader>* manifest_reader,
std::unordered_set<ColumnFamilyData*>* cfds_changed) {
assert(manifest_reader != nullptr);
assert(cfds_changed != nullptr);
mu->AssertHeld();
Status s;
bool have_log_number = false;
bool have_prev_log_number = false;
bool have_next_file = false;
bool have_last_sequence = false;
uint64_t next_file = 0;
uint64_t last_sequence = 0;
uint64_t log_number = 0;
uint64_t previous_log_number = 0;
uint32_t max_column_family = 0;
uint64_t min_log_number_to_keep = 0;
while (s.ok()) {
Slice record;
std::string scratch;
log::Reader* reader = manifest_reader->get();
std::string old_manifest_path = reader->file()->file_name();
while (reader->ReadRecord(&record, &scratch)) {
VersionEdit edit;
s = edit.DecodeFrom(record);
if (!s.ok()) {
break;
}
ColumnFamilyData* cfd =
column_family_set_->GetColumnFamily(edit.column_family_);
// If we cannot find this column family in our column family set, then it
// may be a new column family created by the primary after the secondary
// starts. Ignore it for now.
if (nullptr == cfd) {
continue;
}
if (active_version_builders_.find(edit.column_family_) ==
active_version_builders_.end()) {
std::unique_ptr<BaseReferencedVersionBuilder> builder_guard(
new BaseReferencedVersionBuilder(cfd));
active_version_builders_.insert(
std::make_pair(edit.column_family_, std::move(builder_guard)));
}
s = ApplyOneVersionEditToBuilder(
edit, &have_log_number, &log_number, &have_prev_log_number,
&previous_log_number, &have_next_file, &next_file,
&have_last_sequence, &last_sequence, &min_log_number_to_keep,
&max_column_family);
if (!s.ok()) {
break;
}
auto builder_iter = active_version_builders_.find(edit.column_family_);
assert(builder_iter != active_version_builders_.end());
auto builder = builder_iter->second->version_builder();
assert(builder != nullptr);
s = builder->LoadTableHandlers(
cfd->internal_stats(), db_options_->max_file_opening_threads,
false /* prefetch_index_and_filter_in_cache */,
false /* is_initial_load */,
cfd->GetLatestMutableCFOptions()->prefix_extractor.get());
TEST_SYNC_POINT_CALLBACK(
"ReactiveVersionSet::ReadAndApply:AfterLoadTableHandlers", &s);
if (!s.ok() && !s.IsPathNotFound()) {
break;
} else if (s.IsPathNotFound()) {
s = Status::OK();
} else { // s.ok() == true
auto version = new Version(cfd, this, env_options_,
*cfd->GetLatestMutableCFOptions(),
current_version_number_++);
builder->SaveTo(version->storage_info());
version->PrepareApply(*cfd->GetLatestMutableCFOptions(), true);
AppendVersion(cfd, version);
active_version_builders_.erase(builder_iter);
if (cfds_changed->count(cfd) == 0) {
cfds_changed->insert(cfd);
}
}
if (have_next_file) {
next_file_number_.store(next_file + 1);
}
if (have_last_sequence) {
last_allocated_sequence_ = last_sequence;
last_published_sequence_ = last_sequence;
last_sequence_ = last_sequence;
}
if (have_prev_log_number) {
prev_log_number_ = previous_log_number;
MarkFileNumberUsed(previous_log_number);
}
if (have_log_number) {
MarkFileNumberUsed(log_number);
}
column_family_set_->UpdateMaxColumnFamily(max_column_family);
MarkMinLogNumberToKeep2PC(min_log_number_to_keep);
}
// It's possible that:
// 1) s.IsCorruption(), indicating the current MANIFEST is corrupted.
// 2) we have finished reading the current MANIFEST.
// 3) we have encountered an IOError reading the current MANIFEST.
// We need to look for the next MANIFEST and start from there. If we cannot
// find the next MANIFEST, we should exit the loop.
s = MaybeSwitchManifest(reader->GetReporter(), manifest_reader);
reader = manifest_reader->get();
if (s.ok() && reader->file()->file_name() == old_manifest_path) {
break;
}
}
if (s.ok()) {
for (auto cfd : *column_family_set_) {
auto builder_iter = active_version_builders_.find(cfd->GetID());
if (builder_iter == active_version_builders_.end()) {
continue;
}
auto builder = builder_iter->second->version_builder();
if (!builder->CheckConsistencyForNumLevels()) {
s = Status::InvalidArgument(
"db has more levels than options.num_levels");
break;
}
}
}
return s;
}
Status ReactiveVersionSet::ApplyOneVersionEditToBuilder(
VersionEdit& edit, bool* have_log_number, uint64_t* log_number,
bool* have_prev_log_number, uint64_t* previous_log_number,
bool* have_next_file, uint64_t* next_file, bool* have_last_sequence,
SequenceNumber* last_sequence, uint64_t* min_log_number_to_keep,
uint32_t* max_column_family) {
ColumnFamilyData* cfd = nullptr;
Status status;
if (edit.is_column_family_add_) {
// TODO (yanqin) for now the secondary ignores column families created
// after Open. This also simplifies handling of switching to a new MANIFEST
// and processing the snapshot of the system at the beginning of the
// MANIFEST.
return Status::OK();
} else if (edit.is_column_family_drop_) {
cfd = column_family_set_->GetColumnFamily(edit.column_family_);
// Drop a CF created by primary after secondary starts? Then ignore
if (cfd == nullptr) {
return Status::OK();
}
// Drop the column family by setting it to be 'dropped' without destroying
// the column family handle.
cfd->SetDropped();
if (cfd->Unref()) {
delete cfd;
cfd = nullptr;
}
} else {
cfd = column_family_set_->GetColumnFamily(edit.column_family_);
// Operation on a CF created after Open? Then ignore
if (cfd == nullptr) {
return Status::OK();
}
auto builder_iter = active_version_builders_.find(edit.column_family_);
assert(builder_iter != active_version_builders_.end());
auto builder = builder_iter->second->version_builder();
assert(builder != nullptr);
builder->Apply(&edit);
}
return ExtractInfoFromVersionEdit(
cfd, edit, have_log_number, log_number, have_prev_log_number,
previous_log_number, have_next_file, next_file, have_last_sequence,
last_sequence, min_log_number_to_keep, max_column_family);
}
Status ReactiveVersionSet::MaybeSwitchManifest(
log::Reader::Reporter* reporter,
std::unique_ptr<log::FragmentBufferedReader>* manifest_reader) {
assert(manifest_reader != nullptr);
Status s;
do {
std::string manifest_path;
s = GetCurrentManifestPath(&manifest_path);
std::unique_ptr<SequentialFile> manifest_file;
if (s.ok()) {
if (nullptr == manifest_reader->get() ||
manifest_reader->get()->file()->file_name() != manifest_path) {
TEST_SYNC_POINT(
"ReactiveVersionSet::MaybeSwitchManifest:"
"AfterGetCurrentManifestPath:0");
TEST_SYNC_POINT(
"ReactiveVersionSet::MaybeSwitchManifest:"
"AfterGetCurrentManifestPath:1");
s = env_->NewSequentialFile(
manifest_path, &manifest_file,
env_->OptimizeForManifestRead(env_options_));
} else {
// No need to switch manifest.
break;
}
}
std::unique_ptr<SequentialFileReader> manifest_file_reader;
if (s.ok()) {
manifest_file_reader.reset(
new SequentialFileReader(std::move(manifest_file), manifest_path));
manifest_reader->reset(new log::FragmentBufferedReader(
nullptr, std::move(manifest_file_reader), reporter,
true /* checksum */, 0 /* log_number */));
ROCKS_LOG_INFO(db_options_->info_log, "Switched to new manifest: %s\n",
manifest_path.c_str());
// TODO (yanqin) every time we switch to a new MANIFEST, we clear the
// active_version_builders_ map because we choose to construct the
// versions from scratch, thanks to the first part of each MANIFEST
// written by VersionSet::WriteSnapshot. This is not necessary, but we
// choose this at present for the sake of simplicity.
active_version_builders_.clear();
}
} while (s.IsPathNotFound());
return s;
}
} // namespace rocksdb

94
db/version_set.h
View File

@ -648,6 +648,7 @@ class Version {
private:
Env* env_;
friend class ReactiveVersionSet;
friend class VersionSet;
const InternalKeyComparator* internal_comparator() const {
@ -739,9 +740,7 @@ struct ObsoleteFileInfo {
}
};
namespace {
class BaseReferencedVersionBuilder;
}
class VersionSet {
public:
@ -749,7 +748,7 @@ class VersionSet {
const EnvOptions& env_options, Cache* table_cache,
WriteBufferManager* write_buffer_manager,
WriteController* write_controller);
~VersionSet();
virtual ~VersionSet();
// Apply *edit to the current version to form a new descriptor that
// is both saved to persistent state and installed as the new
@ -795,7 +794,7 @@ class VersionSet {
// The across-multi-cf batch version. If edit_lists contain more than
// 1 version edits, caller must ensure that no edit in the []list is column
// family manipulation.
Status LogAndApply(
virtual Status LogAndApply(
const autovector<ColumnFamilyData*>& cfds,
const autovector<const MutableCFOptions*>& mutable_cf_options_list,
const autovector<autovector<VersionEdit*>>& edit_lists,
@ -803,6 +802,8 @@ class VersionSet {
bool new_descriptor_log = false,
const ColumnFamilyOptions* new_cf_options = nullptr);
Status GetCurrentManifestPath(std::string* manifest_filename);
// Recover the last saved descriptor from persistent storage.
// If read_only == true, Recover() will not complain if some column families
// are not opened
@ -983,11 +984,12 @@ class VersionSet {
static uint64_t GetTotalSstFilesSize(Version* dummy_versions);
private:
protected:
struct ManifestWriter;
friend class Version;
friend class DBImpl;
friend class DBImplReadOnly;
struct LogReporter : public log::Reader::Reporter {
Status* status;
@ -1011,20 +1013,24 @@ class VersionSet {
ColumnFamilyData* CreateColumnFamily(const ColumnFamilyOptions& cf_options,
VersionEdit* edit);
Status ApplyOneVersionEdit(
// REQUIRES db mutex
Status ApplyOneVersionEditToBuilder(
VersionEdit& edit,
const std::unordered_map<std::string, ColumnFamilyOptions>& name_to_opts,
std::unordered_map<int, std::string>& column_families_not_found,
std::unordered_map<uint32_t, BaseReferencedVersionBuilder*>& builders,
std::unordered_map<
uint32_t, std::unique_ptr<BaseReferencedVersionBuilder>>& builders,
bool* have_log_number, uint64_t* log_number, bool* have_prev_log_number,
uint64_t* previous_log_number, bool* have_next_file, uint64_t* next_file,
bool* have_last_sequence, SequenceNumber* last_sequence,
uint64_t* min_log_number_to_keep, uint32_t* max_column_family);
Status ProcessManifestWrites(std::deque<ManifestWriter>& writers,
InstrumentedMutex* mu, Directory* db_directory,
bool new_descriptor_log,
const ColumnFamilyOptions* new_cf_options);
Status ExtractInfoFromVersionEdit(
ColumnFamilyData* cfd, const VersionEdit& edit, bool* have_log_number,
uint64_t* log_number, bool* have_prev_log_number,
uint64_t* previous_log_number, bool* have_next_file, uint64_t* next_file,
bool* have_last_sequence, SequenceNumber* last_sequence,
uint64_t* min_log_number_to_keep, uint32_t* max_column_family);
std::unique_ptr<ColumnFamilySet> column_family_set_;
@ -1074,13 +1080,77 @@ class VersionSet {
// env options for all reads and writes except compactions
EnvOptions env_options_;
private:
// No copying allowed
VersionSet(const VersionSet&);
void operator=(const VersionSet&);
// REQUIRES db mutex at beginning. may release and re-acquire db mutex
Status ProcessManifestWrites(std::deque<ManifestWriter>& writers,
InstrumentedMutex* mu, Directory* db_directory,
bool new_descriptor_log,
const ColumnFamilyOptions* new_cf_options);
void LogAndApplyCFHelper(VersionEdit* edit);
void LogAndApplyHelper(ColumnFamilyData* cfd, VersionBuilder* b, Version* v,
void LogAndApplyHelper(ColumnFamilyData* cfd, VersionBuilder* b,
VersionEdit* edit, InstrumentedMutex* mu);
};
class ReactiveVersionSet : public VersionSet {
public:
ReactiveVersionSet(const std::string& dbname,
const ImmutableDBOptions* _db_options,
const EnvOptions& _env_options, Cache* table_cache,
WriteBufferManager* write_buffer_manager,
WriteController* write_controller);
~ReactiveVersionSet() override;
Status ReadAndApply(
InstrumentedMutex* mu,
std::unique_ptr<log::FragmentBufferedReader>* manifest_reader,
std::unordered_set<ColumnFamilyData*>* cfds_changed);
Status Recover(const std::vector<ColumnFamilyDescriptor>& column_families,
std::unique_ptr<log::FragmentBufferedReader>* manifest_reader,
std::unique_ptr<log::Reader::Reporter>* manifest_reporter,
std::unique_ptr<Status>* manifest_reader_status);
protected:
using VersionSet::ApplyOneVersionEditToBuilder;
// REQUIRES db mutex
Status ApplyOneVersionEditToBuilder(
VersionEdit& edit, bool* have_log_number, uint64_t* log_number,
bool* have_prev_log_number, uint64_t* previous_log_number,
bool* have_next_file, uint64_t* next_file, bool* have_last_sequence,
SequenceNumber* last_sequence, uint64_t* min_log_number_to_keep,
uint32_t* max_column_family);
Status MaybeSwitchManifest(
log::Reader::Reporter* reporter,
std::unique_ptr<log::FragmentBufferedReader>* manifest_reader);
private:
std::unordered_map<uint32_t, std::unique_ptr<BaseReferencedVersionBuilder>>
active_version_builders_;
using VersionSet::LogAndApply;
using VersionSet::Recover;
Status LogAndApply(
const autovector<ColumnFamilyData*>& /*cfds*/,
const autovector<const MutableCFOptions*>& /*mutable_cf_options_list*/,
const autovector<autovector<VersionEdit*>>& /*edit_lists*/,
InstrumentedMutex* /*mu*/, Directory* /*db_directory*/,
bool /*new_descriptor_log*/,
const ColumnFamilyOptions* /*new_cf_option*/) override {
return Status::NotSupported("not supported in reactive mode");
}
// No copy allowed
ReactiveVersionSet(const ReactiveVersionSet&);
ReactiveVersionSet& operator=(const ReactiveVersionSet&);
};
} // namespace rocksdb

2
db/wal_manager.cc
View File

@ -457,7 +457,7 @@ Status WalManager::ReadFirstLine(const std::string& fname,
reporter.status = &status;
reporter.ignore_error = !db_options_.paranoid_checks;
log::Reader reader(db_options_.info_log, std::move(file_reader), &reporter,
true /*checksum*/, number, false /* retry_after_eof */);
true /*checksum*/, number);
std::string scratch;
Slice record;

8
env/env_hdfs.cc vendored
View File

@ -36,9 +36,11 @@ namespace {
// Log error message
static Status IOError(const std::string& context, int err_number) {
return (err_number == ENOSPC) ?
Status::NoSpace(context, strerror(err_number)) :
Status::IOError(context, strerror(err_number));
return (err_number == ENOSPC)
? Status::NoSpace(context, strerror(err_number))
: (err_number == ENOENT)
? Status::PathNotFound(context, strerror(err_number))
: Status::IOError(context, strerror(err_number));
}
// assume that there is one global logger for now. It is not thread-safe,

3
env/io_posix.h vendored
View File

@ -41,6 +41,9 @@ static Status IOError(const std::string& context, const std::string& file_name,
strerror(err_number));
case ESTALE:
return Status::IOError(Status::kStaleFile);
case ENOENT:
return Status::PathNotFound(IOErrorMsg(context, file_name),
strerror(err_number));
default:
return Status::IOError(IOErrorMsg(context, file_name),
strerror(err_number));

1
examples/.gitignore vendored
View File

@ -2,6 +2,7 @@ c_simple_example
column_families_example
compact_files_example
compaction_filter_example
multi_processes_example
optimistic_transaction_example
options_file_example
simple_example

5
examples/Makefile
View File

@ -43,8 +43,11 @@ transaction_example: librocksdb transaction_example.cc
options_file_example: librocksdb options_file_example.cc
$(CXX) $(CXXFLAGS) $@.cc -o$@ ../librocksdb.a -I../include -O2 -std=c++11 $(PLATFORM_LDFLAGS) $(PLATFORM_CXXFLAGS) $(EXEC_LDFLAGS)
multi_processes_example: librocksdb multi_processes_example.cc
$(CXX) $(CXXFLAGS) $@.cc -o$@ ../librocksdb.a -I../include -O2 -std=c++11 $(PLATFORM_LDFLAGS) $(PLATFORM_CXXFLAGS) $(EXEC_LDFLAGS)
clean:
rm -rf ./simple_example ./column_families_example ./compact_files_example ./compaction_filter_example ./c_simple_example c_simple_example.o ./optimistic_transaction_example ./transaction_example ./options_file_example
rm -rf ./simple_example ./column_families_example ./compact_files_example ./compaction_filter_example ./c_simple_example c_simple_example.o ./optimistic_transaction_example ./transaction_example ./options_file_example ./multi_processes_example
librocksdb:
cd .. && $(MAKE) static_lib

395
examples/multi_processes_example.cc Normal file
View File

@ -0,0 +1,395 @@
// Copyright (c) 2011-present, Facebook, Inc. All rights reserved.
// This source code is licensed under both the GPLv2 (found in the
// COPYING file in the root directory) and Apache 2.0 License
// (found in the LICENSE.Apache file in the root directory).
// How to use this example
// Open two terminals, in one of them, run `./multi_processes_example 0` to
// start a process running the primary instance. This will create a new DB in
// kDBPath. The process will run for a while inserting keys to the normal
// RocksDB database.
// Next, go to the other terminal and run `./multi_processes_example 1` to
// start a process running the secondary instance. This will create a secondary
// instance following the aforementioned primary instance. This process will
// run for a while, tailing the logs of the primary. After process with primary
// instance exits, this process will keep running until you hit 'CTRL+C'.
#include <inttypes.h>
#include <chrono>
#include <cstdio>
#include <cstdlib>
#include <ctime>
#include <string>
#include <thread>
#include <vector>
#if defined(OS_LINUX)
#include <dirent.h>
#include <signal.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <unistd.h>
#endif // !OS_LINUX
#include "rocksdb/db.h"
#include "rocksdb/options.h"
#include "rocksdb/slice.h"
using rocksdb::ColumnFamilyDescriptor;
using rocksdb::ColumnFamilyHandle;
using rocksdb::ColumnFamilyOptions;
using rocksdb::DB;
using rocksdb::FlushOptions;
using rocksdb::Iterator;
using rocksdb::Options;
using rocksdb::ReadOptions;
using rocksdb::Slice;
using rocksdb::Status;
using rocksdb::WriteOptions;
const std::string kDBPath = "/tmp/rocksdb_multi_processes_example";
const std::string kPrimaryStatusFile =
"/tmp/rocksdb_multi_processes_example_primary_status";
const uint64_t kMaxKey = 600000;
const size_t kMaxValueLength = 256;
const size_t kNumKeysPerFlush = 1000;
const std::vector<std::string>& GetColumnFamilyNames() {
static std::vector<std::string> column_family_names = {
rocksdb::kDefaultColumnFamilyName, "pikachu"};
return column_family_names;
}
inline bool IsLittleEndian() {
uint32_t x = 1;
return *reinterpret_cast<char*>(&x) != 0;
}
static std::atomic<int>& ShouldSecondaryWait() {
static std::atomic<int> should_secondary_wait{1};
return should_secondary_wait;
}
static std::string Key(uint64_t k) {
std::string ret;
if (IsLittleEndian()) {
ret.append(reinterpret_cast<char*>(&k), sizeof(k));
} else {
char buf[sizeof(k)];
buf[0] = k & 0xff;
buf[1] = (k >> 8) & 0xff;
buf[2] = (k >> 16) & 0xff;
buf[3] = (k >> 24) & 0xff;
buf[4] = (k >> 32) & 0xff;
buf[5] = (k >> 40) & 0xff;
buf[6] = (k >> 48) & 0xff;
buf[7] = (k >> 56) & 0xff;
ret.append(buf, sizeof(k));
}
size_t i = 0, j = ret.size() - 1;
while (i < j) {
char tmp = ret[i];
ret[i] = ret[j];
ret[j] = tmp;
++i;
--j;
}
return ret;
}
static uint64_t Key(std::string key) {
assert(key.size() == sizeof(uint64_t));
size_t i = 0, j = key.size() - 1;
while (i < j) {
char tmp = key[i];
key[i] = key[j];
key[j] = tmp;
++i;
--j;
}
uint64_t ret = 0;
if (IsLittleEndian()) {
memcpy(&ret, key.c_str(), sizeof(uint64_t));
} else {
const char* buf = key.c_str();
ret |= static_cast<uint64_t>(buf[0]);
ret |= (static_cast<uint64_t>(buf[1]) << 8);
ret |= (static_cast<uint64_t>(buf[2]) << 16);
ret |= (static_cast<uint64_t>(buf[3]) << 24);
ret |= (static_cast<uint64_t>(buf[4]) << 32);
ret |= (static_cast<uint64_t>(buf[5]) << 40);
ret |= (static_cast<uint64_t>(buf[6]) << 48);
ret |= (static_cast<uint64_t>(buf[7]) << 56);
}
return ret;
}
static Slice GenerateRandomValue(const size_t max_length, char scratch[]) {
size_t sz = 1 + (std::rand() % max_length);
int rnd = std::rand();
for (size_t i = 0; i != sz; ++i) {
scratch[i] = static_cast<char>(rnd ^ i);
}
return Slice(scratch, sz);
}
static bool ShouldCloseDB() { return true; }
// TODO: port this example to other systems. It should be straightforward for
// POSIX-compliant systems.
#if defined(OS_LINUX)
void CreateDB() {
long my_pid = static_cast<long>(getpid());
Options options;
Status s = rocksdb::DestroyDB(kDBPath, options);
if (!s.ok()) {
fprintf(stderr, "[process %ld] Failed to destroy DB: %s\n", my_pid,
s.ToString().c_str());
assert(false);
}
options.create_if_missing = true;
DB* db = nullptr;
s = DB::Open(options, kDBPath, &db);
if (!s.ok()) {
fprintf(stderr, "[process %ld] Failed to open DB: %s\n", my_pid,
s.ToString().c_str());
assert(false);
}
std::vector<ColumnFamilyHandle*> handles;
ColumnFamilyOptions cf_opts(options);
for (const auto& cf_name : GetColumnFamilyNames()) {
if (rocksdb::kDefaultColumnFamilyName != cf_name) {
ColumnFamilyHandle* handle = nullptr;
s = db->CreateColumnFamily(cf_opts, cf_name, &handle);
if (!s.ok()) {
fprintf(stderr, "[process %ld] Failed to create CF %s: %s\n", my_pid,
cf_name.c_str(), s.ToString().c_str());
assert(false);
}
handles.push_back(handle);
}
}
fprintf(stdout, "[process %ld] Column families created\n", my_pid);
for (auto h : handles) {
delete h;
}
handles.clear();
delete db;
}
void RunPrimary() {
long my_pid = static_cast<long>(getpid());
fprintf(stdout, "[process %ld] Primary instance starts\n", my_pid);
CreateDB();
std::srand(time(nullptr));
DB* db = nullptr;
Options options;
options.create_if_missing = false;
std::vector<ColumnFamilyDescriptor> column_families;
for (const auto& cf_name : GetColumnFamilyNames()) {
column_families.push_back(ColumnFamilyDescriptor(cf_name, options));
}
std::vector<ColumnFamilyHandle*> handles;
WriteOptions write_opts;
char val_buf[kMaxValueLength] = {0};
uint64_t curr_key = 0;
while (curr_key < kMaxKey) {
Status s;
if (nullptr == db) {
s = DB::Open(options, kDBPath, column_families, &handles, &db);
if (!s.ok()) {
fprintf(stderr, "[process %ld] Failed to open DB: %s\n", my_pid,
s.ToString().c_str());
assert(false);
}
}
assert(nullptr != db);
assert(handles.size() == GetColumnFamilyNames().size());
for (auto h : handles) {
assert(nullptr != h);
for (size_t i = 0; i != kNumKeysPerFlush; ++i) {
Slice key = Key(curr_key + static_cast<uint64_t>(i));
Slice value = GenerateRandomValue(kMaxValueLength, val_buf);
s = db->Put(write_opts, h, key, value);
if (!s.ok()) {
fprintf(stderr, "[process %ld] Failed to insert\n", my_pid);
assert(false);
}
}
s = db->Flush(FlushOptions(), h);
if (!s.ok()) {
fprintf(stderr, "[process %ld] Failed to flush\n", my_pid);
assert(false);
}
}
curr_key += static_cast<uint64_t>(kNumKeysPerFlush);
if (ShouldCloseDB()) {
for (auto h : handles) {
delete h;
}
handles.clear();
delete db;
db = nullptr;
}
}
if (nullptr != db) {
for (auto h : handles) {
delete h;
}
handles.clear();
delete db;
db = nullptr;
}
fprintf(stdout, "[process %ld] Finished adding keys\n", my_pid);
}
void secondary_instance_sigint_handler(int signal) {
ShouldSecondaryWait().store(0, std::memory_order_relaxed);
fprintf(stdout, "\n");
fflush(stdout);
};
void RunSecondary() {
::signal(SIGINT, secondary_instance_sigint_handler);
long my_pid = static_cast<long>(getpid());
const std::string kSecondaryPath =
"/tmp/rocksdb_multi_processes_example_secondary";
// Create directory if necessary
if (nullptr == opendir(kSecondaryPath.c_str())) {
int ret =
mkdir(kSecondaryPath.c_str(), S_IRWXU | S_IRWXG | S_IROTH | S_IXOTH);
if (ret < 0) {
perror("failed to create directory for secondary instance");
exit(0);
}
}
DB* db = nullptr;
Options options;
options.create_if_missing = false;
options.max_open_files = -1;
Status s = DB::OpenAsSecondary(options, kDBPath, kSecondaryPath, &db);
if (!s.ok()) {
fprintf(stderr, "[process %ld] Failed to open in secondary mode: %s\n",
my_pid, s.ToString().c_str());
assert(false);
} else {
fprintf(stdout, "[process %ld] Secondary instance starts\n", my_pid);
}
ReadOptions ropts;
ropts.verify_checksums = true;
ropts.total_order_seek = true;
std::vector<std::thread> test_threads;
test_threads.emplace_back([&]() {
while (1 == ShouldSecondaryWait().load(std::memory_order_relaxed)) {
std::unique_ptr<Iterator> iter(db->NewIterator(ropts));
iter->SeekToFirst();
size_t count = 0;
for (; iter->Valid(); iter->Next()) {
++count;
}
}
fprintf(stdout, "[process %ld] Range_scan thread finished\n", my_pid);
});
test_threads.emplace_back([&]() {
std::srand(time(nullptr));
while (1 == ShouldSecondaryWait().load(std::memory_order_relaxed)) {
Slice key = Key(std::rand() % kMaxKey);
std::string value;
db->Get(ropts, key, &value);
}
fprintf(stdout, "[process %ld] Point lookup thread finished\n");
});
uint64_t curr_key = 0;
while (1 == ShouldSecondaryWait().load(std::memory_order_relaxed)) {
s = db->TryCatchUpWithPrimary();
if (!s.ok()) {
fprintf(stderr,
"[process %ld] error while trying to catch up with "
"primary %s\n",
my_pid, s.ToString().c_str());
assert(false);
}
{
std::unique_ptr<Iterator> iter(db->NewIterator(ropts));
if (!iter) {
fprintf(stderr, "[process %ld] Failed to create iterator\n", my_pid);
assert(false);
}
iter->SeekToLast();
if (iter->Valid()) {
uint64_t curr_max_key = Key(iter->key().ToString());
if (curr_max_key != curr_key) {
fprintf(stdout, "[process %ld] Observed key %" PRIu64 "\n", my_pid,
curr_key);
curr_key = curr_max_key;
}
}
}
std::this_thread::sleep_for(std::chrono::seconds(1));
}
s = db->TryCatchUpWithPrimary();
if (!s.ok()) {
fprintf(stderr,
"[process %ld] error while trying to catch up with "
"primary %s\n",
my_pid, s.ToString().c_str());
assert(false);
}
std::vector<ColumnFamilyDescriptor> column_families;
for (const auto& cf_name : GetColumnFamilyNames()) {
column_families.push_back(ColumnFamilyDescriptor(cf_name, options));
}
std::vector<ColumnFamilyHandle*> handles;
DB* verification_db = nullptr;
s = DB::OpenForReadOnly(options, kDBPath, column_families, &handles,
&verification_db);
assert(s.ok());
Iterator* iter1 = verification_db->NewIterator(ropts);
iter1->SeekToFirst();
Iterator* iter = db->NewIterator(ropts);
iter->SeekToFirst();
for (; iter->Valid() && iter1->Valid(); iter->Next(), iter1->Next()) {
if (iter->key().ToString() != iter1->key().ToString()) {
fprintf(stderr, "%" PRIu64 "!= %" PRIu64 "\n",
Key(iter->key().ToString()), Key(iter1->key().ToString()));
assert(false);
} else if (iter->value().ToString() != iter1->value().ToString()) {
fprintf(stderr, "Value mismatch\n");
assert(false);
}
}
fprintf(stdout, "[process %ld] Verification succeeded\n", my_pid);
for (auto& thr : test_threads) {
thr.join();
}
delete iter;
delete iter1;
delete db;
delete verification_db;
}
int main(int argc, char** argv) {
if (argc < 2) {
fprintf(stderr, "%s <0 for primary, 1 for secondary>\n", argv[0]);
return 0;
}
if (atoi(argv[1]) == 0) {
RunPrimary();
} else {
RunSecondary();
}
return 0;
}
#else // OS_LINUX
int main() {
fpritnf(stderr, "Not implemented.\n");
return 0;
}
#endif // !OS_LINUX

65
include/rocksdb/db.h
View File

@ -162,6 +162,54 @@ class DB {
std::vector<ColumnFamilyHandle*>* handles, DB** dbptr,
bool error_if_log_file_exist = false);
// The following OpenAsSecondary functions create a secondary instance that
// can dynamically tail the MANIFEST of a primary that must have already been
// created. User can call TryCatchUpWithPrimary to make the secondary
// instance catch up with primary (WAL tailing is NOT supported now) whenever
// the user feels necessary. Column families created by the primary after the
// secondary instance starts are currently ignored by the secondary instance.
// Column families opened by secondary and dropped by the primary will be
// dropped by secondary as well. However the user of the secondary instance
// can still access the data of such dropped column family as long as they
// do not destroy the corresponding column family handle.
// WAL tailing is not supported at present, but will arrive soon.
//
// The options argument specifies the options to open the secondary instance.
// The name argument specifies the name of the primary db that you have used
// to open the primary instance.
// The secondary_path argument points to a directory where the secondary
// instance stores its info log.
// The dbptr is an out-arg corresponding to the opened secondary instance.
// The pointer points to a heap-allocated database, and the user should
// delete it after use.
// Open DB as secondary instance with only the default column family.
// Return OK on success, non-OK on failures.
static Status OpenAsSecondary(const Options& options, const std::string& name,
const std::string& secondary_path, DB** dbptr);
// Open DB as secondary instance with column families. You can open a subset
// of column families in secondary mode.
// The db_options specify the database specific options.
// The name argument specifies the name of the primary db that you have used
// to open the primary instance.
// The secondary_path argument points to a directory where the secondary
// instance stores its info log.
// The column_families argument specifieds a list of column families to open.
// If any of the column families does not exist, the function returns non-OK
// status.
// The handles is an out-arg corresponding to the opened database column
// familiy handles.
// The dbptr is an out-arg corresponding to the opened secondary instance.
// The pointer points to a heap-allocated database, and the caller should
// delete it after use. Before deleting the dbptr, the user should also
// delete the pointers stored in handles vector.
// Return OK on success, on-OK on failures.
static Status OpenAsSecondary(
const DBOptions& db_options, const std::string& name,
const std::string& secondary_path,
const std::vector<ColumnFamilyDescriptor>& column_families,
std::vector<ColumnFamilyHandle*>* handles, DB** dbptr);
// Open DB with column families.
// db_options specify database specific options
// column_families is the vector of all column families in the database,
@ -1235,6 +1283,23 @@ class DB {
return Status::NotSupported("GetStatsHistory() is not implemented.");
}
#ifndef ROCKSDB_LITE
// Make the secondary instance catch up with the primary by tailing and
// replaying the MANIFEST and WAL of the primary.
// Column families created by the primary after the secondary instance starts
// will be ignored unless the secondary instance closes and restarts with the
// newly created column families.
// Column families that exist before secondary instance starts and dropped by
// the primary afterwards will be marked as dropped. However, as long as the
// secondary instance does not delete the corresponding column family
// handles, the data of the column family is still accessible to the
// secondary.
// TODO: we will support WAL tailing soon.
virtual Status TryCatchUpWithPrimary() {
return Status::NotSupported("Supported only by secondary instance");
}
#endif // !ROCKSDB_LITE
private:
// No copying allowed
DB(const DB&);

14
include/rocksdb/status.h
View File

@ -73,6 +73,7 @@ class Status {
kStaleFile = 6,
kMemoryLimit = 7,
kSpaceLimit = 8,
kPathNotFound = 9,
kMaxSubCode
};
@ -198,6 +199,11 @@ class Status {
return Status(kIOError, kSpaceLimit, msg, msg2);
}
static Status PathNotFound() { return Status(kIOError, kPathNotFound); }
static Status PathNotFound(const Slice& msg, const Slice& msg2 = Slice()) {
return Status(kIOError, kPathNotFound, msg, msg2);
}
// Returns true iff the status indicates success.
bool ok() const { return code() == kOk; }
@ -266,6 +272,14 @@ class Status {
return (code() == kAborted) && (subcode() == kMemoryLimit);
}
// Returns true iff the status indicates a PathNotFound error
// This is caused by an I/O error returning the specific "no such file or
// directory" error condition. A PathNotFound error is an I/O error with
// a specific subcode, enabling users to take appropriate action if necessary
bool IsPathNotFound() const {
return (code() == kIOError) && (subcode() == kPathNotFound);
}
// Return a string representation of this status suitable for printing.
// Returns the string "OK" for success.
std::string ToString() const;

12
port/win/io_win.h
View File

@ -27,7 +27,9 @@ std::string GetWindowsErrSz(DWORD err);
inline Status IOErrorFromWindowsError(const std::string& context, DWORD err) {
return ((err == ERROR_HANDLE_DISK_FULL) || (err == ERROR_DISK_FULL))
? Status::NoSpace(context, GetWindowsErrSz(err))
: Status::IOError(context, GetWindowsErrSz(err));
: ((err == ERROR_FILE_NOT_FOUND) || (err == ERROR_PATH_NOT_FOUND))
? Status::PathNotFound(context, GetWindowsErrSz(err))
: Status::IOError(context, GetWindowsErrSz(err));
}
inline Status IOErrorFromLastWindowsError(const std::string& context) {
@ -37,7 +39,9 @@ inline Status IOErrorFromLastWindowsError(const std::string& context) {
inline Status IOError(const std::string& context, int err_number) {
return (err_number == ENOSPC)
? Status::NoSpace(context, strerror(err_number))
: Status::IOError(context, strerror(err_number));
: (err_number == ENOENT)
? Status::PathNotFound(context, strerror(err_number))
: Status::IOError(context, strerror(err_number));
}
class WinFileData;
@ -426,9 +430,7 @@ public:
class WinDirectory : public Directory {
HANDLE handle_;
public:
explicit
WinDirectory(HANDLE h) noexcept :
handle_(h) {
explicit WinDirectory(HANDLE h) noexcept : handle_(h) {
assert(handle_ != INVALID_HANDLE_VALUE);
}
~WinDirectory() {

2
src.mk
View File

@ -22,6 +22,7 @@ LIB_SOURCES = \
db/db_impl_files.cc \
db/db_impl_open.cc \
db/db_impl_readonly.cc \
db/db_impl_secondary.cc \
db/db_impl_write.cc \
db/db_info_dumper.cc \
db/db_iter.cc \
@ -279,6 +280,7 @@ MAIN_SOURCES = \
db/db_options_test.cc \
db/db_properties_test.cc \
db/db_range_del_test.cc \
db/db_secondary_test.cc \
db/db_sst_test.cc \
db/db_statistics_test.cc \
db/db_table_properties_test.cc \

3
tools/ldb_cmd.cc
View File

@ -2014,8 +2014,7 @@ void DumpWalFile(Options options, std::string wal_file, bool print_header,
log_number = 0;
}
log::Reader reader(options.info_log, std::move(wal_file_reader), &reporter,
true /* checksum */, log_number,
false /* retry_after_eof */);
true /* checksum */, log_number);
std::string scratch;
WriteBatch batch;
Slice record;

3
util/status.cc
View File

@ -41,7 +41,8 @@ static const char* msgs[static_cast<int>(Status::kMaxSubCode)] = {
"Deadlock", // kDeadlock
"Stale file handle", // kStaleFile
"Memory limit reached", // kMemoryLimit
"Space limit reached" // kSpaceLimit
"Space limit reached", // kSpaceLimit
"No such file or directory", // kPathNotFound
};
Status::Status(Code _code, SubCode _subcode, const Slice& msg,