rocksdb/db/db_impl/db_impl_secondary.cc
anand76 0ed93552f4 Implement obsolete file deletion (GC) in follower (#12657)
Summary:
This PR implements deletion of obsolete files in a follower RocksDB instance. The follower tails the leader's MANIFEST and creates links to newly added SST files. These links need to be deleted once those files become obsolete in order to reclaim space. There are three cases to be considered -
1. New files added and links created, but the Version could not be installed due to some missing files. Those links need to be preserved so a subsequent catch up attempt can succeed. We insert the next file number in the `VersionSet` to `pending_outputs_` to prevent their deletion.
2. Files deleted from the previous successfully installed `Version`. These are deleted as usual in `PurgeObsoleteFiles`.
3. New files added by a `VersionEdit` and deleted by a subsequent `VersionEdit`, both processed in the same catchup attempt. Links will be created for the new files when verifying a candidate `Version`. Those need to be deleted explicitly as they're never added to `VersionStorageInfo`, and thus not deleted by `PurgeObsoleteFiles`.

Test plan -
New unit tests in `db_follower_test`.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/12657

Reviewed By: jowlyzhang

Differential Revision: D57462697

Pulled By: anand1976

fbshipit-source-id: 898f15570638dd4930f839ffd31c560f9cb73916
2024-05-17 19:13:33 -07:00

1026 lines
38 KiB
C++

// 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/db_impl_secondary.h"
#include <cinttypes>
#include "db/arena_wrapped_db_iter.h"
#include "db/merge_context.h"
#include "logging/auto_roll_logger.h"
#include "logging/logging.h"
#include "monitoring/perf_context_imp.h"
#include "rocksdb/configurable.h"
#include "util/cast_util.h"
#include "util/write_batch_util.h"
namespace ROCKSDB_NAMESPACE {
DBImplSecondary::DBImplSecondary(const DBOptions& db_options,
const std::string& dbname,
std::string secondary_path)
: DBImpl(db_options, dbname, false, true, true),
secondary_path_(std::move(secondary_path)) {
ROCKS_LOG_INFO(immutable_db_options_.info_log,
"Opening the db in secondary mode");
LogFlush(immutable_db_options_.info_log);
}
DBImplSecondary::~DBImplSecondary() = default;
Status DBImplSecondary::Recover(
const std::vector<ColumnFamilyDescriptor>& column_families,
bool /*readonly*/, bool /*error_if_wal_file_exists*/,
bool /*error_if_data_exists_in_wals*/, bool /*is_retry*/, uint64_t*,
RecoveryContext* /*recovery_ctx*/, bool* /*can_retry*/) {
mutex_.AssertHeld();
JobContext job_context(0);
Status s;
s = static_cast<ReactiveVersionSet*>(versions_.get())
->Recover(column_families, &manifest_reader_, &manifest_reporter_,
&manifest_reader_status_);
if (!s.ok()) {
if (manifest_reader_status_) {
manifest_reader_status_->PermitUncheckedError();
}
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();
std::unordered_set<ColumnFamilyData*> cfds_changed;
s = FindAndRecoverLogFiles(&cfds_changed, &job_context);
}
if (s.IsPathNotFound()) {
ROCKS_LOG_INFO(immutable_db_options_.info_log,
"Secondary tries to read WAL, but WAL file(s) have already "
"been purged by primary.");
s = Status::OK();
}
// TODO: update options_file_number_ needed?
job_context.Clean();
return s;
}
// find new WAL and apply them in order to the secondary instance
Status DBImplSecondary::FindAndRecoverLogFiles(
std::unordered_set<ColumnFamilyData*>* cfds_changed,
JobContext* job_context) {
assert(nullptr != cfds_changed);
assert(nullptr != job_context);
Status s;
std::vector<uint64_t> logs;
s = FindNewLogNumbers(&logs);
if (s.ok() && !logs.empty()) {
SequenceNumber next_sequence(kMaxSequenceNumber);
s = RecoverLogFiles(logs, &next_sequence, cfds_changed, job_context);
}
return s;
}
// List wal_dir and find all new WALs, return these log numbers
Status DBImplSecondary::FindNewLogNumbers(std::vector<uint64_t>* logs) {
assert(logs != nullptr);
std::vector<std::string> filenames;
Status s;
IOOptions io_opts;
io_opts.do_not_recurse = true;
s = immutable_db_options_.fs->GetChildren(immutable_db_options_.GetWalDir(),
io_opts, &filenames,
/*IODebugContext*=*/nullptr);
if (s.IsNotFound()) {
return Status::InvalidArgument("Failed to open wal_dir",
immutable_db_options_.GetWalDir());
} else if (!s.ok()) {
return s;
}
// if log_readers_ is non-empty, it means we have applied all logs with log
// numbers smaller than the smallest log in log_readers_, so there is no
// need to pass these logs to RecoverLogFiles
uint64_t log_number_min = 0;
if (!log_readers_.empty()) {
log_number_min = log_readers_.begin()->first;
}
for (size_t i = 0; i < filenames.size(); i++) {
uint64_t number;
FileType type;
if (ParseFileName(filenames[i], &number, &type) && type == kWalFile &&
number >= log_number_min) {
logs->push_back(number);
}
}
// Recover logs in the order that they were generated
if (!logs->empty()) {
std::sort(logs->begin(), logs->end());
}
return s;
}
Status DBImplSecondary::MaybeInitLogReader(
uint64_t log_number, log::FragmentBufferedReader** log_reader) {
auto iter = log_readers_.find(log_number);
// make sure the log file is still present
if (iter == log_readers_.end() ||
iter->second->reader_->GetLogNumber() != log_number) {
// delete the obsolete log reader if log number mismatch
if (iter != log_readers_.end()) {
log_readers_.erase(iter);
}
// initialize log reader from log_number
// TODO: min_log_number_to_keep_2pc check needed?
// Open the log file
std::string fname =
LogFileName(immutable_db_options_.GetWalDir(), log_number);
ROCKS_LOG_INFO(immutable_db_options_.info_log,
"Recovering log #%" PRIu64 " mode %d", log_number,
static_cast<int>(immutable_db_options_.wal_recovery_mode));
std::unique_ptr<SequentialFileReader> file_reader;
{
std::unique_ptr<FSSequentialFile> file;
Status status = fs_->NewSequentialFile(
fname, fs_->OptimizeForLogRead(file_options_), &file, nullptr);
if (!status.ok()) {
*log_reader = nullptr;
return status;
}
file_reader.reset(new SequentialFileReader(
std::move(file), fname, immutable_db_options_.log_readahead_size,
io_tracer_));
}
// Create the log reader.
LogReaderContainer* log_reader_container = new LogReaderContainer(
env_, immutable_db_options_.info_log, std::move(fname),
std::move(file_reader), log_number);
log_readers_.insert(std::make_pair(
log_number, std::unique_ptr<LogReaderContainer>(log_reader_container)));
}
iter = log_readers_.find(log_number);
assert(iter != log_readers_.end());
*log_reader = iter->second->reader_;
return Status::OK();
}
// After manifest recovery, replay WALs and refresh log_readers_ if necessary
// REQUIRES: log_numbers are sorted in ascending order
Status DBImplSecondary::RecoverLogFiles(
const std::vector<uint64_t>& log_numbers, SequenceNumber* next_sequence,
std::unordered_set<ColumnFamilyData*>* cfds_changed,
JobContext* job_context) {
assert(nullptr != cfds_changed);
assert(nullptr != job_context);
mutex_.AssertHeld();
Status status;
for (auto log_number : log_numbers) {
log::FragmentBufferedReader* reader = nullptr;
status = MaybeInitLogReader(log_number, &reader);
if (!status.ok()) {
return status;
}
assert(reader != nullptr);
}
const UnorderedMap<uint32_t, size_t>& running_ts_sz =
versions_->GetRunningColumnFamiliesTimestampSize();
for (auto log_number : log_numbers) {
auto it = log_readers_.find(log_number);
assert(it != log_readers_.end());
log::FragmentBufferedReader* reader = it->second->reader_;
Status* wal_read_status = it->second->status_;
assert(wal_read_status);
// Manually update the file number allocation counter in VersionSet.
versions_->MarkFileNumberUsed(log_number);
// Determine if we should tolerate incomplete records at the tail end of the
// Read all the records and add to a memtable
std::string scratch;
Slice record;
WriteBatch batch;
while (reader->ReadRecord(&record, &scratch,
immutable_db_options_.wal_recovery_mode) &&
wal_read_status->ok() && status.ok()) {
if (record.size() < WriteBatchInternal::kHeader) {
reader->GetReporter()->Corruption(
record.size(), Status::Corruption("log record too small"));
continue;
}
status = WriteBatchInternal::SetContents(&batch, record);
if (!status.ok()) {
break;
}
const UnorderedMap<uint32_t, size_t>& record_ts_sz =
reader->GetRecordedTimestampSize();
status = HandleWriteBatchTimestampSizeDifference(
&batch, running_ts_sz, record_ts_sz,
TimestampSizeConsistencyMode::kVerifyConsistency);
if (!status.ok()) {
break;
}
SequenceNumber seq_of_batch = WriteBatchInternal::Sequence(&batch);
std::vector<uint32_t> column_family_ids;
status = CollectColumnFamilyIdsFromWriteBatch(batch, &column_family_ids);
if (status.ok()) {
for (const auto id : column_family_ids) {
ColumnFamilyData* cfd =
versions_->GetColumnFamilySet()->GetColumnFamily(id);
if (cfd == nullptr) {
continue;
}
if (cfds_changed->count(cfd) == 0) {
cfds_changed->insert(cfd);
}
const std::vector<FileMetaData*>& l0_files =
cfd->current()->storage_info()->LevelFiles(0);
SequenceNumber seq =
l0_files.empty() ? 0 : l0_files.back()->fd.largest_seqno;
// If the write batch's sequence number is smaller than the last
// sequence number of the largest sequence persisted for this column
// family, then its data must reside in an SST that has already been
// added in the prior MANIFEST replay.
if (seq_of_batch <= seq) {
continue;
}
auto curr_log_num = std::numeric_limits<uint64_t>::max();
if (cfd_to_current_log_.count(cfd) > 0) {
curr_log_num = cfd_to_current_log_[cfd];
}
// If the active memtable contains records added by replaying an
// earlier WAL, then we need to seal the memtable, add it to the
// immutable memtable list and create a new active memtable.
if (!cfd->mem()->IsEmpty() &&
(curr_log_num == std::numeric_limits<uint64_t>::max() ||
curr_log_num != log_number)) {
const MutableCFOptions mutable_cf_options =
*cfd->GetLatestMutableCFOptions();
MemTable* new_mem =
cfd->ConstructNewMemtable(mutable_cf_options, seq_of_batch);
cfd->mem()->SetNextLogNumber(log_number);
cfd->mem()->ConstructFragmentedRangeTombstones();
cfd->imm()->Add(cfd->mem(), &job_context->memtables_to_free);
new_mem->Ref();
cfd->SetMemtable(new_mem);
}
}
bool has_valid_writes = false;
status = WriteBatchInternal::InsertInto(
&batch, column_family_memtables_.get(),
nullptr /* flush_scheduler */, nullptr /* trim_history_scheduler*/,
true, log_number, this, false /* concurrent_memtable_writes */,
next_sequence, &has_valid_writes, seq_per_batch_, batch_per_txn_);
}
// If column family was not found, it might mean that the WAL write
// batch references to the column family that was dropped after the
// insert. We don't want to fail the whole write batch in that case --
// we just ignore the update.
// That's why we set ignore missing column families to true
// passing null flush_scheduler will disable memtable flushing which is
// needed for secondary instances
if (status.ok()) {
for (const auto id : column_family_ids) {
ColumnFamilyData* cfd =
versions_->GetColumnFamilySet()->GetColumnFamily(id);
if (cfd == nullptr) {
continue;
}
std::unordered_map<ColumnFamilyData*, uint64_t>::iterator iter =
cfd_to_current_log_.find(cfd);
if (iter == cfd_to_current_log_.end()) {
cfd_to_current_log_.insert({cfd, log_number});
} else if (log_number > iter->second) {
iter->second = log_number;
}
}
auto last_sequence = *next_sequence - 1;
if ((*next_sequence != kMaxSequenceNumber) &&
(versions_->LastSequence() <= last_sequence)) {
versions_->SetLastAllocatedSequence(last_sequence);
versions_->SetLastPublishedSequence(last_sequence);
versions_->SetLastSequence(last_sequence);
}
} else {
// We are treating this as a failure while reading since we read valid
// blocks that do not form coherent data
reader->GetReporter()->Corruption(record.size(), status);
}
}
if (status.ok() && !wal_read_status->ok()) {
status = *wal_read_status;
}
if (!status.ok()) {
wal_read_status->PermitUncheckedError();
return status;
}
}
// remove logreaders from map after successfully recovering the WAL
if (log_readers_.size() > 1) {
auto erase_iter = log_readers_.begin();
std::advance(erase_iter, log_readers_.size() - 1);
log_readers_.erase(log_readers_.begin(), erase_iter);
}
return status;
}
Status DBImplSecondary::GetImpl(const ReadOptions& read_options,
const Slice& key,
GetImplOptions& get_impl_options) {
assert(get_impl_options.value != nullptr ||
get_impl_options.columns != nullptr);
assert(get_impl_options.column_family);
Status s;
if (read_options.timestamp) {
s = FailIfTsMismatchCf(get_impl_options.column_family,
*(read_options.timestamp));
if (!s.ok()) {
return s;
}
} else {
s = FailIfCfHasTs(get_impl_options.column_family);
if (!s.ok()) {
return s;
}
}
// Clear the timestamps for returning results so that we can distinguish
// between tombstone or key that has never been written
if (get_impl_options.timestamp) {
get_impl_options.timestamp->clear();
}
PERF_CPU_TIMER_GUARD(get_cpu_nanos, immutable_db_options_.clock);
StopWatch sw(immutable_db_options_.clock, stats_, DB_GET);
PERF_TIMER_GUARD(get_snapshot_time);
const Comparator* ucmp = get_impl_options.column_family->GetComparator();
assert(ucmp);
std::string* ts =
ucmp->timestamp_size() > 0 ? get_impl_options.timestamp : nullptr;
SequenceNumber snapshot = versions_->LastSequence();
GetWithTimestampReadCallback read_cb(snapshot);
auto cfh = static_cast_with_check<ColumnFamilyHandleImpl>(
get_impl_options.column_family);
auto cfd = cfh->cfd();
if (tracer_) {
InstrumentedMutexLock lock(&trace_mutex_);
if (tracer_) {
tracer_->Get(get_impl_options.column_family, key);
}
}
// Acquire SuperVersion
SuperVersion* super_version = GetAndRefSuperVersion(cfd);
if (read_options.timestamp && read_options.timestamp->size() > 0) {
s = FailIfReadCollapsedHistory(cfd, super_version,
*(read_options.timestamp));
if (!s.ok()) {
ReturnAndCleanupSuperVersion(cfd, super_version);
return s;
}
}
MergeContext merge_context;
SequenceNumber max_covering_tombstone_seq = 0;
LookupKey lkey(key, snapshot, read_options.timestamp);
PERF_TIMER_STOP(get_snapshot_time);
bool done = false;
// Look up starts here
if (super_version->mem->Get(
lkey,
get_impl_options.value ? get_impl_options.value->GetSelf() : nullptr,
get_impl_options.columns, ts, &s, &merge_context,
&max_covering_tombstone_seq, read_options,
false /* immutable_memtable */, &read_cb)) {
done = true;
if (get_impl_options.value) {
get_impl_options.value->PinSelf();
}
RecordTick(stats_, MEMTABLE_HIT);
} else if ((s.ok() || s.IsMergeInProgress()) &&
super_version->imm->Get(
lkey,
get_impl_options.value ? get_impl_options.value->GetSelf()
: nullptr,
get_impl_options.columns, ts, &s, &merge_context,
&max_covering_tombstone_seq, read_options, &read_cb)) {
done = true;
if (get_impl_options.value) {
get_impl_options.value->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);
PinnedIteratorsManager pinned_iters_mgr;
super_version->current->Get(
read_options, lkey, get_impl_options.value, get_impl_options.columns,
ts, &s, &merge_context, &max_covering_tombstone_seq, &pinned_iters_mgr,
/*value_found*/ nullptr,
/*key_exists*/ nullptr, /*seq*/ nullptr, &read_cb, /*is_blob*/ nullptr,
/*do_merge*/ true);
RecordTick(stats_, MEMTABLE_MISS);
}
{
PERF_TIMER_GUARD(get_post_process_time);
ReturnAndCleanupSuperVersion(cfd, super_version);
RecordTick(stats_, NUMBER_KEYS_READ);
size_t size = 0;
if (get_impl_options.value) {
size = get_impl_options.value->size();
} else if (get_impl_options.columns) {
size = get_impl_options.columns->serialized_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.io_activity != Env::IOActivity::kUnknown &&
_read_options.io_activity != Env::IOActivity::kDBIterator) {
return NewErrorIterator(Status::InvalidArgument(
"Can only call NewIterator with `ReadOptions::io_activity` is "
"`Env::IOActivity::kUnknown` or `Env::IOActivity::kDBIterator`"));
}
ReadOptions read_options(_read_options);
if (read_options.io_activity == Env::IOActivity::kUnknown) {
read_options.io_activity = Env::IOActivity::kDBIterator;
}
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."));
}
assert(column_family);
if (read_options.timestamp) {
const Status s =
FailIfTsMismatchCf(column_family, *(read_options.timestamp));
if (!s.ok()) {
return NewErrorIterator(s);
}
} else {
const Status s = FailIfCfHasTs(column_family);
if (!s.ok()) {
return NewErrorIterator(s);
}
}
Iterator* result = nullptr;
auto cfh = static_cast_with_check<ColumnFamilyHandleImpl>(column_family);
assert(cfh != nullptr);
auto cfd = cfh->cfd();
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 {
SequenceNumber snapshot(kMaxSequenceNumber);
SuperVersion* sv = cfd->GetReferencedSuperVersion(this);
if (read_options.timestamp && read_options.timestamp->size() > 0) {
const Status s =
FailIfReadCollapsedHistory(cfd, sv, *(read_options.timestamp));
if (!s.ok()) {
CleanupSuperVersion(sv);
return NewErrorIterator(s);
}
}
result = NewIteratorImpl(read_options, cfh, sv, snapshot,
nullptr /*read_callback*/);
}
return result;
}
ArenaWrappedDBIter* DBImplSecondary::NewIteratorImpl(
const ReadOptions& read_options, ColumnFamilyHandleImpl* cfh,
SuperVersion* super_version, SequenceNumber snapshot,
ReadCallback* read_callback, bool expose_blob_index, bool allow_refresh) {
assert(nullptr != cfh);
assert(snapshot == kMaxSequenceNumber);
snapshot = versions_->LastSequence();
assert(snapshot != kMaxSequenceNumber);
auto db_iter = NewArenaWrappedDbIterator(
env_, read_options, *cfh->cfd()->ioptions(),
super_version->mutable_cf_options, super_version->current, snapshot,
super_version->mutable_cf_options.max_sequential_skip_in_iterations,
super_version->version_number, read_callback, cfh, expose_blob_index,
allow_refresh);
auto internal_iter = NewInternalIterator(
db_iter->GetReadOptions(), cfh->cfd(), super_version, db_iter->GetArena(),
snapshot, /* allow_unprepared_value */ true, db_iter);
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.io_activity != Env::IOActivity::kUnknown &&
_read_options.io_activity != Env::IOActivity::kDBIterator) {
return Status::InvalidArgument(
"Can only call NewIterators with `ReadOptions::io_activity` is "
"`Env::IOActivity::kUnknown` or `Env::IOActivity::kDBIterator`");
}
ReadOptions read_options(_read_options);
if (read_options.io_activity == Env::IOActivity::kUnknown) {
read_options.io_activity = Env::IOActivity::kDBIterator;
}
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");
}
if (read_options.timestamp) {
for (auto* cf : column_families) {
assert(cf);
const Status s = FailIfTsMismatchCf(cf, *(read_options.timestamp));
if (!s.ok()) {
return s;
}
}
} else {
for (auto* cf : column_families) {
assert(cf);
const Status s = FailIfCfHasTs(cf);
if (!s.ok()) {
return s;
}
}
}
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(kMaxSequenceNumber);
autovector<std::tuple<ColumnFamilyHandleImpl*, SuperVersion*>> cfh_to_sv;
const bool check_read_ts =
read_options.timestamp && read_options.timestamp->size() > 0;
for (auto cf : column_families) {
auto cfh = static_cast_with_check<ColumnFamilyHandleImpl>(cf);
auto cfd = cfh->cfd();
SuperVersion* sv = cfd->GetReferencedSuperVersion(this);
cfh_to_sv.emplace_back(cfh, sv);
if (check_read_ts) {
const Status s =
FailIfReadCollapsedHistory(cfd, sv, *(read_options.timestamp));
if (!s.ok()) {
for (auto prev_entry : cfh_to_sv) {
CleanupSuperVersion(std::get<1>(prev_entry));
}
return s;
}
}
}
assert(cfh_to_sv.size() == column_families.size());
for (auto [cfh, sv] : cfh_to_sv) {
iterators->push_back(
NewIteratorImpl(read_options, cfh, sv, read_seq, read_callback));
}
}
return Status::OK();
}
Status DBImplSecondary::CheckConsistency() {
mutex_.AssertHeld();
Status s = DBImpl::CheckConsistency();
// If DBImpl::CheckConsistency() which is stricter returns success, then we
// do not need to give a second chance.
if (s.ok()) {
return s;
}
// It's possible that DBImpl::CheckConssitency() can fail because the primary
// may have removed certain files, causing the GetFileSize(name) call to
// fail and returning a PathNotFound. In this case, we take a best-effort
// approach and just proceed.
TEST_SYNC_POINT_CALLBACK(
"DBImplSecondary::CheckConsistency:AfterFirstAttempt", &s);
if (immutable_db_options_.skip_checking_sst_file_sizes_on_db_open) {
return Status::OK();
}
std::vector<LiveFileMetaData> metadata;
versions_->GetLiveFilesMetaData(&metadata);
std::string corruption_messages;
for (const auto& md : metadata) {
// md.name has a leading "/".
std::string file_path = md.db_path + md.name;
uint64_t fsize = 0;
s = env_->GetFileSize(file_path, &fsize);
if (!s.ok() &&
(env_->GetFileSize(Rocks2LevelTableFileName(file_path), &fsize).ok() ||
s.IsPathNotFound())) {
s = Status::OK();
}
if (!s.ok()) {
corruption_messages +=
"Can't access " + md.name + ": " + s.ToString() + "\n";
}
}
return corruption_messages.empty() ? Status::OK()
: Status::Corruption(corruption_messages);
}
Status DBImplSecondary::TryCatchUpWithPrimary() {
assert(versions_.get() != nullptr);
assert(manifest_reader_.get() != nullptr);
Status s;
// read the manifest and apply new changes to the secondary instance
std::unordered_set<ColumnFamilyData*> cfds_changed;
JobContext job_context(0, true /*create_superversion*/);
{
InstrumentedMutexLock lock_guard(&mutex_);
s = static_cast_with_check<ReactiveVersionSet>(versions_.get())
->ReadAndApply(&mutex_, &manifest_reader_,
manifest_reader_status_.get(), &cfds_changed,
/*files_to_delete=*/nullptr);
ROCKS_LOG_INFO(immutable_db_options_.info_log, "Last sequence is %" PRIu64,
static_cast<uint64_t>(versions_->LastSequence()));
for (ColumnFamilyData* cfd : cfds_changed) {
if (cfd->IsDropped()) {
ROCKS_LOG_DEBUG(immutable_db_options_.info_log, "[%s] is dropped\n",
cfd->GetName().c_str());
continue;
}
VersionStorageInfo::LevelSummaryStorage tmp;
ROCKS_LOG_DEBUG(immutable_db_options_.info_log,
"[%s] Level summary: %s\n", cfd->GetName().c_str(),
cfd->current()->storage_info()->LevelSummary(&tmp));
}
// list wal_dir to discover new WALs and apply new changes to the secondary
// instance
if (s.ok()) {
s = FindAndRecoverLogFiles(&cfds_changed, &job_context);
}
if (s.IsPathNotFound()) {
ROCKS_LOG_INFO(
immutable_db_options_.info_log,
"Secondary tries to read WAL, but WAL file(s) have already "
"been purged by primary.");
s = Status::OK();
}
if (s.ok()) {
for (auto cfd : cfds_changed) {
cfd->imm()->RemoveOldMemTables(cfd->GetLogNumber(),
&job_context.memtables_to_free);
auto& sv_context = job_context.superversion_contexts.back();
cfd->InstallSuperVersion(&sv_context, &mutex_);
sv_context.NewSuperVersion();
}
}
}
job_context.Clean();
// Cleanup unused, obsolete files.
JobContext purge_files_job_context(0);
{
InstrumentedMutexLock lock_guard(&mutex_);
// Currently, secondary instance does not own the database files, thus it
// is unnecessary for the secondary to force full scan.
FindObsoleteFiles(&purge_files_job_context, /*force=*/false);
}
if (purge_files_job_context.HaveSomethingToDelete()) {
PurgeObsoleteFiles(purge_files_job_context);
}
purge_files_job_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;
DBOptions tmp_opts(db_options);
Status s;
if (nullptr == tmp_opts.info_log) {
s = CreateLoggerFromOptions(secondary_path, tmp_opts, &tmp_opts.info_log);
if (!s.ok()) {
tmp_opts.info_log = nullptr;
return s;
}
}
assert(tmp_opts.info_log != nullptr);
if (db_options.max_open_files != -1) {
std::ostringstream oss;
oss << "The primary instance may delete all types of files after they "
"become obsolete. The application can coordinate the primary and "
"secondary so that primary does not delete/rename files that are "
"currently being used by the secondary. Alternatively, a custom "
"Env/FS can be provided such that files become inaccessible only "
"after all primary and secondaries indicate that they are obsolete "
"and deleted. If the above two are not possible, you can open the "
"secondary instance with `max_open_files==-1` so that secondary "
"will eagerly keep all table files open. Even if a file is deleted, "
"its content can still be accessed via a prior open file "
"descriptor. This is a hacky workaround for only table files. If "
"none of the above is done, then point lookup or "
"range scan via the secondary instance can result in IOError: file "
"not found. This can be resolved by retrying "
"TryCatchUpWithPrimary().";
ROCKS_LOG_WARN(tmp_opts.info_log, "%s", oss.str().c_str());
}
handles->clear();
DBImplSecondary* impl = new DBImplSecondary(tmp_opts, dbname, secondary_path);
impl->versions_.reset(new ReactiveVersionSet(
dbname, &impl->immutable_db_options_, impl->file_options_,
impl->table_cache_.get(), impl->write_buffer_manager_,
&impl->write_controller_, impl->io_tracer_));
impl->column_family_memtables_.reset(
new ColumnFamilyMemTablesImpl(impl->versions_->GetColumnFamilySet()));
impl->wal_in_db_path_ = impl->immutable_db_options_.IsWalDirSameAsDBPath();
impl->mutex_.Lock();
s = impl->Recover(column_families, true, false, false);
if (s.ok()) {
for (const 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(
static_cast_with_check<ColumnFamilyHandleImpl>(h)->cfd());
}
} else {
for (auto h : *handles) {
delete h;
}
handles->clear();
delete impl;
}
return s;
}
Status DBImplSecondary::CompactWithoutInstallation(
const OpenAndCompactOptions& options, ColumnFamilyHandle* cfh,
const CompactionServiceInput& input, CompactionServiceResult* result) {
if (options.canceled && options.canceled->load(std::memory_order_acquire)) {
return Status::Incomplete(Status::SubCode::kManualCompactionPaused);
}
InstrumentedMutexLock l(&mutex_);
auto cfd = static_cast_with_check<ColumnFamilyHandleImpl>(cfh)->cfd();
if (!cfd) {
return Status::InvalidArgument("Cannot find column family" +
cfh->GetName());
}
std::unordered_set<uint64_t> input_set;
for (const auto& file_name : input.input_files) {
input_set.insert(TableFileNameToNumber(file_name));
}
auto* version = cfd->current();
ColumnFamilyMetaData cf_meta;
version->GetColumnFamilyMetaData(&cf_meta);
const MutableCFOptions* mutable_cf_options = cfd->GetLatestMutableCFOptions();
ColumnFamilyOptions cf_options = cfd->GetLatestCFOptions();
VersionStorageInfo* vstorage = version->storage_info();
// Use comp_options to reuse some CompactFiles functions
CompactionOptions comp_options;
comp_options.compression = kDisableCompressionOption;
comp_options.output_file_size_limit = MaxFileSizeForLevel(
*mutable_cf_options, input.output_level, cf_options.compaction_style,
vstorage->base_level(), cf_options.level_compaction_dynamic_level_bytes);
std::vector<CompactionInputFiles> input_files;
Status s = cfd->compaction_picker()->GetCompactionInputsFromFileNumbers(
&input_files, &input_set, vstorage, comp_options);
if (!s.ok()) {
return s;
}
std::unique_ptr<Compaction> c;
assert(cfd->compaction_picker());
c.reset(cfd->compaction_picker()->CompactFiles(
comp_options, input_files, input.output_level, vstorage,
*mutable_cf_options, mutable_db_options_, 0));
assert(c != nullptr);
c->FinalizeInputInfo(version);
// Create output directory if it's not existed yet
std::unique_ptr<FSDirectory> output_dir;
s = CreateAndNewDirectory(fs_.get(), secondary_path_, &output_dir);
if (!s.ok()) {
return s;
}
LogBuffer log_buffer(InfoLogLevel::INFO_LEVEL,
immutable_db_options_.info_log.get());
const int job_id = next_job_id_.fetch_add(1);
// use primary host's db_id for running the compaction, but db_session_id is
// using the local one, which is to make sure the unique id is unique from
// the remote compactors. Because the id is generated from db_id,
// db_session_id and orig_file_number, unlike the local compaction, remote
// compaction cannot guarantee the uniqueness of orig_file_number, the file
// number is only assigned when compaction is done.
CompactionServiceCompactionJob compaction_job(
job_id, c.get(), immutable_db_options_, mutable_db_options_,
file_options_for_compaction_, versions_.get(), &shutting_down_,
&log_buffer, output_dir.get(), stats_, &mutex_, &error_handler_,
input.snapshots, table_cache_, &event_logger_, dbname_, io_tracer_,
options.canceled ? *options.canceled : kManualCompactionCanceledFalse_,
input.db_id, db_session_id_, secondary_path_, input, result);
mutex_.Unlock();
s = compaction_job.Run();
mutex_.Lock();
// clean up
compaction_job.io_status().PermitUncheckedError();
compaction_job.CleanupCompaction();
c->ReleaseCompactionFiles(s);
c.reset();
TEST_SYNC_POINT_CALLBACK("DBImplSecondary::CompactWithoutInstallation::End",
&s);
result->status = s;
return s;
}
Status DB::OpenAndCompact(
const OpenAndCompactOptions& options, const std::string& name,
const std::string& output_directory, const std::string& input,
std::string* output,
const CompactionServiceOptionsOverride& override_options) {
if (options.canceled && options.canceled->load(std::memory_order_acquire)) {
return Status::Incomplete(Status::SubCode::kManualCompactionPaused);
}
CompactionServiceInput compaction_input;
Status s = CompactionServiceInput::Read(input, &compaction_input);
if (!s.ok()) {
return s;
}
compaction_input.db_options.max_open_files = -1;
compaction_input.db_options.compaction_service = nullptr;
if (compaction_input.db_options.statistics) {
compaction_input.db_options.statistics.reset();
}
compaction_input.db_options.env = override_options.env;
compaction_input.db_options.file_checksum_gen_factory =
override_options.file_checksum_gen_factory;
compaction_input.db_options.statistics = override_options.statistics;
compaction_input.column_family.options.comparator =
override_options.comparator;
compaction_input.column_family.options.merge_operator =
override_options.merge_operator;
compaction_input.column_family.options.compaction_filter =
override_options.compaction_filter;
compaction_input.column_family.options.compaction_filter_factory =
override_options.compaction_filter_factory;
compaction_input.column_family.options.prefix_extractor =
override_options.prefix_extractor;
compaction_input.column_family.options.table_factory =
override_options.table_factory;
compaction_input.column_family.options.sst_partitioner_factory =
override_options.sst_partitioner_factory;
compaction_input.column_family.options.table_properties_collector_factories =
override_options.table_properties_collector_factories;
compaction_input.db_options.listeners = override_options.listeners;
std::vector<ColumnFamilyDescriptor> column_families;
column_families.push_back(compaction_input.column_family);
// TODO: we have to open default CF, because of an implementation limitation,
// currently we just use the same CF option from input, which is not collect
// and open may fail.
if (compaction_input.column_family.name != kDefaultColumnFamilyName) {
column_families.emplace_back(kDefaultColumnFamilyName,
compaction_input.column_family.options);
}
DB* db;
std::vector<ColumnFamilyHandle*> handles;
s = DB::OpenAsSecondary(compaction_input.db_options, name, output_directory,
column_families, &handles, &db);
if (!s.ok()) {
return s;
}
CompactionServiceResult compaction_result;
DBImplSecondary* db_secondary = static_cast_with_check<DBImplSecondary>(db);
assert(handles.size() > 0);
s = db_secondary->CompactWithoutInstallation(
options, handles[0], compaction_input, &compaction_result);
Status serialization_status = compaction_result.Write(output);
for (auto& handle : handles) {
delete handle;
}
delete db;
if (s.ok()) {
return serialization_status;
} else {
serialization_status.PermitUncheckedError();
}
return s;
}
Status DB::OpenAndCompact(
const std::string& name, const std::string& output_directory,
const std::string& input, std::string* output,
const CompactionServiceOptionsOverride& override_options) {
return OpenAndCompact(OpenAndCompactOptions(), name, output_directory, input,
output, override_options);
}
} // namespace ROCKSDB_NAMESPACE