80de900464
Summary: We have observed an increase in CPU load caused by frequent calls to `ColumnFamilyData::InstallSuperVersion` from `DBImpl::TrimMemtableHistory` when using `max_write_buffer_size_to_maintain` to limit the amount of memtable history maintained for transaction conflict checking. As it turns out, this is caused by the code creating and installing a new `SuperVersion` even if no memtables were actually trimmed. The patch adds a check to avoid this. Pull Request resolved: https://github.com/facebook/rocksdb/pull/6169 Test Plan: Compared `perf` output for ``` ./db_bench -benchmarks=randomtransaction -optimistic_transaction_db=1 -statistics -stats_interval_seconds=1 -duration=90 -num=500000 --max_write_buffer_size_to_maintain=16000000 --transaction_set_snapshot=1 --threads=32 ``` before and after the change. With the fix, the call chain `rocksdb::DBImpl::TrimMemtableHistory` -> `rocksdb::ColumnFamilyData::InstallSuperVersion` -> `rocksdb::ThreadLocalPtr::StaticMeta::Scrape` no longer registers in the `perf` report. Differential Revision: D19031509 Pulled By: ltamasi fbshipit-source-id: 02686fce594e5b50eba0710e4b28a9b808c8aa20
1833 lines
67 KiB
C++
1833 lines
67 KiB
C++
// Copyright (c) 2011-present, Facebook, Inc. All rights reserved.
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// This source code is licensed under both the GPLv2 (found in the
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// COPYING file in the root directory) and Apache 2.0 License
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// (found in the LICENSE.Apache file in the root directory).
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//
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// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style license that can be
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// found in the LICENSE file. See the AUTHORS file for names of contributors.
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#include "db/db_impl/db_impl.h"
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#include <cinttypes>
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#include "db/error_handler.h"
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#include "db/event_helpers.h"
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#include "monitoring/perf_context_imp.h"
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#include "options/options_helper.h"
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#include "test_util/sync_point.h"
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namespace rocksdb {
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// Convenience methods
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Status DBImpl::Put(const WriteOptions& o, ColumnFamilyHandle* column_family,
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const Slice& key, const Slice& val) {
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return DB::Put(o, column_family, key, val);
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}
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Status DBImpl::Merge(const WriteOptions& o, ColumnFamilyHandle* column_family,
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const Slice& key, const Slice& val) {
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auto cfh = reinterpret_cast<ColumnFamilyHandleImpl*>(column_family);
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if (!cfh->cfd()->ioptions()->merge_operator) {
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return Status::NotSupported("Provide a merge_operator when opening DB");
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} else {
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return DB::Merge(o, column_family, key, val);
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}
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}
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Status DBImpl::Delete(const WriteOptions& write_options,
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ColumnFamilyHandle* column_family, const Slice& key) {
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return DB::Delete(write_options, column_family, key);
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}
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Status DBImpl::SingleDelete(const WriteOptions& write_options,
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ColumnFamilyHandle* column_family,
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const Slice& key) {
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return DB::SingleDelete(write_options, column_family, key);
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}
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void DBImpl::SetRecoverableStatePreReleaseCallback(
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PreReleaseCallback* callback) {
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recoverable_state_pre_release_callback_.reset(callback);
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}
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Status DBImpl::Write(const WriteOptions& write_options, WriteBatch* my_batch) {
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return WriteImpl(write_options, my_batch, nullptr, nullptr);
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}
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#ifndef ROCKSDB_LITE
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Status DBImpl::WriteWithCallback(const WriteOptions& write_options,
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WriteBatch* my_batch,
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WriteCallback* callback) {
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return WriteImpl(write_options, my_batch, callback, nullptr);
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}
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#endif // ROCKSDB_LITE
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// The main write queue. This is the only write queue that updates LastSequence.
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// When using one write queue, the same sequence also indicates the last
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// published sequence.
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Status DBImpl::WriteImpl(const WriteOptions& write_options,
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WriteBatch* my_batch, WriteCallback* callback,
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uint64_t* log_used, uint64_t log_ref,
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bool disable_memtable, uint64_t* seq_used,
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size_t batch_cnt,
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PreReleaseCallback* pre_release_callback) {
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assert(!seq_per_batch_ || batch_cnt != 0);
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if (my_batch == nullptr) {
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return Status::Corruption("Batch is nullptr!");
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}
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if (tracer_) {
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InstrumentedMutexLock lock(&trace_mutex_);
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if (tracer_) {
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tracer_->Write(my_batch);
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}
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}
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if (write_options.sync && write_options.disableWAL) {
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return Status::InvalidArgument("Sync writes has to enable WAL.");
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}
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if (two_write_queues_ && immutable_db_options_.enable_pipelined_write) {
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return Status::NotSupported(
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"pipelined_writes is not compatible with concurrent prepares");
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}
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if (seq_per_batch_ && immutable_db_options_.enable_pipelined_write) {
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// TODO(yiwu): update pipeline write with seq_per_batch and batch_cnt
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return Status::NotSupported(
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"pipelined_writes is not compatible with seq_per_batch");
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}
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if (immutable_db_options_.unordered_write &&
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immutable_db_options_.enable_pipelined_write) {
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return Status::NotSupported(
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"pipelined_writes is not compatible with unordered_write");
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}
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// Otherwise IsLatestPersistentState optimization does not make sense
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assert(!WriteBatchInternal::IsLatestPersistentState(my_batch) ||
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disable_memtable);
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Status status;
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if (write_options.low_pri) {
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status = ThrottleLowPriWritesIfNeeded(write_options, my_batch);
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if (!status.ok()) {
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return status;
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}
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}
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if (two_write_queues_ && disable_memtable) {
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AssignOrder assign_order =
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seq_per_batch_ ? kDoAssignOrder : kDontAssignOrder;
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// Otherwise it is WAL-only Prepare batches in WriteCommitted policy and
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// they don't consume sequence.
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return WriteImplWALOnly(&nonmem_write_thread_, write_options, my_batch,
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callback, log_used, log_ref, seq_used, batch_cnt,
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pre_release_callback, assign_order,
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kDontPublishLastSeq, disable_memtable);
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}
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if (immutable_db_options_.unordered_write) {
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const size_t sub_batch_cnt = batch_cnt != 0
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? batch_cnt
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// every key is a sub-batch consuming a seq
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: WriteBatchInternal::Count(my_batch);
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uint64_t seq;
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// Use a write thread to i) optimize for WAL write, ii) publish last
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// sequence in in increasing order, iii) call pre_release_callback serially
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status = WriteImplWALOnly(&write_thread_, write_options, my_batch, callback,
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log_used, log_ref, &seq, sub_batch_cnt,
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pre_release_callback, kDoAssignOrder,
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kDoPublishLastSeq, disable_memtable);
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if (!status.ok()) {
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return status;
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}
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if (seq_used) {
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*seq_used = seq;
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}
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if (!disable_memtable) {
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status = UnorderedWriteMemtable(write_options, my_batch, callback,
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log_ref, seq, sub_batch_cnt);
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}
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return status;
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}
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if (immutable_db_options_.enable_pipelined_write) {
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return PipelinedWriteImpl(write_options, my_batch, callback, log_used,
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log_ref, disable_memtable, seq_used);
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}
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PERF_TIMER_GUARD(write_pre_and_post_process_time);
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WriteThread::Writer w(write_options, my_batch, callback, log_ref,
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disable_memtable, batch_cnt, pre_release_callback);
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if (!write_options.disableWAL) {
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RecordTick(stats_, WRITE_WITH_WAL);
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}
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StopWatch write_sw(env_, immutable_db_options_.statistics.get(), DB_WRITE);
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write_thread_.JoinBatchGroup(&w);
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if (w.state == WriteThread::STATE_PARALLEL_MEMTABLE_WRITER) {
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// we are a non-leader in a parallel group
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if (w.ShouldWriteToMemtable()) {
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PERF_TIMER_STOP(write_pre_and_post_process_time);
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PERF_TIMER_GUARD(write_memtable_time);
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ColumnFamilyMemTablesImpl column_family_memtables(
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versions_->GetColumnFamilySet());
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w.status = WriteBatchInternal::InsertInto(
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&w, w.sequence, &column_family_memtables, &flush_scheduler_,
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&trim_history_scheduler_,
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write_options.ignore_missing_column_families, 0 /*log_number*/, this,
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true /*concurrent_memtable_writes*/, seq_per_batch_, w.batch_cnt,
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batch_per_txn_, write_options.memtable_insert_hint_per_batch);
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PERF_TIMER_START(write_pre_and_post_process_time);
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}
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if (write_thread_.CompleteParallelMemTableWriter(&w)) {
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// we're responsible for exit batch group
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// TODO(myabandeh): propagate status to write_group
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auto last_sequence = w.write_group->last_sequence;
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versions_->SetLastSequence(last_sequence);
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MemTableInsertStatusCheck(w.status);
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write_thread_.ExitAsBatchGroupFollower(&w);
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}
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assert(w.state == WriteThread::STATE_COMPLETED);
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// STATE_COMPLETED conditional below handles exit
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status = w.FinalStatus();
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}
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if (w.state == WriteThread::STATE_COMPLETED) {
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if (log_used != nullptr) {
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*log_used = w.log_used;
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}
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if (seq_used != nullptr) {
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*seq_used = w.sequence;
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}
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// write is complete and leader has updated sequence
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return w.FinalStatus();
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}
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// else we are the leader of the write batch group
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assert(w.state == WriteThread::STATE_GROUP_LEADER);
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// Once reaches this point, the current writer "w" will try to do its write
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// job. It may also pick up some of the remaining writers in the "writers_"
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// when it finds suitable, and finish them in the same write batch.
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// This is how a write job could be done by the other writer.
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WriteContext write_context;
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WriteThread::WriteGroup write_group;
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bool in_parallel_group = false;
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uint64_t last_sequence = kMaxSequenceNumber;
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mutex_.Lock();
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bool need_log_sync = write_options.sync;
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bool need_log_dir_sync = need_log_sync && !log_dir_synced_;
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if (!two_write_queues_ || !disable_memtable) {
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// With concurrent writes we do preprocess only in the write thread that
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// also does write to memtable to avoid sync issue on shared data structure
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// with the other thread
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// PreprocessWrite does its own perf timing.
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PERF_TIMER_STOP(write_pre_and_post_process_time);
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status = PreprocessWrite(write_options, &need_log_sync, &write_context);
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if (!two_write_queues_) {
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// Assign it after ::PreprocessWrite since the sequence might advance
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// inside it by WriteRecoverableState
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last_sequence = versions_->LastSequence();
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}
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PERF_TIMER_START(write_pre_and_post_process_time);
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}
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log::Writer* log_writer = logs_.back().writer;
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mutex_.Unlock();
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// Add to log and apply to memtable. We can release the lock
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// during this phase since &w is currently responsible for logging
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// and protects against concurrent loggers and concurrent writes
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// into memtables
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TEST_SYNC_POINT("DBImpl::WriteImpl:BeforeLeaderEnters");
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last_batch_group_size_ =
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write_thread_.EnterAsBatchGroupLeader(&w, &write_group);
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if (status.ok()) {
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// Rules for when we can update the memtable concurrently
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// 1. supported by memtable
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// 2. Puts are not okay if inplace_update_support
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// 3. Merges are not okay
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//
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// Rules 1..2 are enforced by checking the options
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// during startup (CheckConcurrentWritesSupported), so if
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// options.allow_concurrent_memtable_write is true then they can be
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// assumed to be true. Rule 3 is checked for each batch. We could
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// relax rules 2 if we could prevent write batches from referring
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// more than once to a particular key.
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bool parallel = immutable_db_options_.allow_concurrent_memtable_write &&
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write_group.size > 1;
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size_t total_count = 0;
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size_t valid_batches = 0;
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size_t total_byte_size = 0;
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size_t pre_release_callback_cnt = 0;
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for (auto* writer : write_group) {
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if (writer->CheckCallback(this)) {
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valid_batches += writer->batch_cnt;
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if (writer->ShouldWriteToMemtable()) {
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total_count += WriteBatchInternal::Count(writer->batch);
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parallel = parallel && !writer->batch->HasMerge();
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}
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total_byte_size = WriteBatchInternal::AppendedByteSize(
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total_byte_size, WriteBatchInternal::ByteSize(writer->batch));
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if (writer->pre_release_callback) {
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pre_release_callback_cnt++;
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}
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}
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}
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// Note about seq_per_batch_: either disableWAL is set for the entire write
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// group or not. In either case we inc seq for each write batch with no
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// failed callback. This means that there could be a batch with
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// disalbe_memtable in between; although we do not write this batch to
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// memtable it still consumes a seq. Otherwise, if !seq_per_batch_, we inc
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// the seq per valid written key to mem.
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size_t seq_inc = seq_per_batch_ ? valid_batches : total_count;
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const bool concurrent_update = two_write_queues_;
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// Update stats while we are an exclusive group leader, so we know
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// that nobody else can be writing to these particular stats.
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// We're optimistic, updating the stats before we successfully
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// commit. That lets us release our leader status early.
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auto stats = default_cf_internal_stats_;
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stats->AddDBStats(InternalStats::kIntStatsNumKeysWritten, total_count,
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concurrent_update);
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RecordTick(stats_, NUMBER_KEYS_WRITTEN, total_count);
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stats->AddDBStats(InternalStats::kIntStatsBytesWritten, total_byte_size,
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concurrent_update);
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RecordTick(stats_, BYTES_WRITTEN, total_byte_size);
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stats->AddDBStats(InternalStats::kIntStatsWriteDoneBySelf, 1,
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concurrent_update);
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RecordTick(stats_, WRITE_DONE_BY_SELF);
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auto write_done_by_other = write_group.size - 1;
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if (write_done_by_other > 0) {
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stats->AddDBStats(InternalStats::kIntStatsWriteDoneByOther,
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write_done_by_other, concurrent_update);
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RecordTick(stats_, WRITE_DONE_BY_OTHER, write_done_by_other);
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}
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RecordInHistogram(stats_, BYTES_PER_WRITE, total_byte_size);
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if (write_options.disableWAL) {
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has_unpersisted_data_.store(true, std::memory_order_relaxed);
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}
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PERF_TIMER_STOP(write_pre_and_post_process_time);
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if (!two_write_queues_) {
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if (status.ok() && !write_options.disableWAL) {
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PERF_TIMER_GUARD(write_wal_time);
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status = WriteToWAL(write_group, log_writer, log_used, need_log_sync,
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need_log_dir_sync, last_sequence + 1);
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}
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} else {
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if (status.ok() && !write_options.disableWAL) {
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PERF_TIMER_GUARD(write_wal_time);
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// LastAllocatedSequence is increased inside WriteToWAL under
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// wal_write_mutex_ to ensure ordered events in WAL
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status = ConcurrentWriteToWAL(write_group, log_used, &last_sequence,
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seq_inc);
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} else {
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// Otherwise we inc seq number for memtable writes
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last_sequence = versions_->FetchAddLastAllocatedSequence(seq_inc);
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}
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}
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assert(last_sequence != kMaxSequenceNumber);
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const SequenceNumber current_sequence = last_sequence + 1;
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last_sequence += seq_inc;
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// PreReleaseCallback is called after WAL write and before memtable write
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if (status.ok()) {
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SequenceNumber next_sequence = current_sequence;
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size_t index = 0;
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// Note: the logic for advancing seq here must be consistent with the
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// logic in WriteBatchInternal::InsertInto(write_group...) as well as
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// with WriteBatchInternal::InsertInto(write_batch...) that is called on
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// the merged batch during recovery from the WAL.
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for (auto* writer : write_group) {
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if (writer->CallbackFailed()) {
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continue;
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}
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writer->sequence = next_sequence;
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if (writer->pre_release_callback) {
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Status ws = writer->pre_release_callback->Callback(
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writer->sequence, disable_memtable, writer->log_used, index++,
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pre_release_callback_cnt);
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if (!ws.ok()) {
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status = ws;
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break;
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}
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}
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if (seq_per_batch_) {
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assert(writer->batch_cnt);
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next_sequence += writer->batch_cnt;
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} else if (writer->ShouldWriteToMemtable()) {
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next_sequence += WriteBatchInternal::Count(writer->batch);
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}
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}
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}
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if (status.ok()) {
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PERF_TIMER_GUARD(write_memtable_time);
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if (!parallel) {
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// w.sequence will be set inside InsertInto
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w.status = WriteBatchInternal::InsertInto(
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write_group, current_sequence, column_family_memtables_.get(),
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&flush_scheduler_, &trim_history_scheduler_,
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write_options.ignore_missing_column_families,
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0 /*recovery_log_number*/, this, parallel, seq_per_batch_,
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batch_per_txn_);
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} else {
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write_group.last_sequence = last_sequence;
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write_thread_.LaunchParallelMemTableWriters(&write_group);
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in_parallel_group = true;
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// Each parallel follower is doing each own writes. The leader should
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// also do its own.
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if (w.ShouldWriteToMemtable()) {
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ColumnFamilyMemTablesImpl column_family_memtables(
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versions_->GetColumnFamilySet());
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assert(w.sequence == current_sequence);
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w.status = WriteBatchInternal::InsertInto(
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&w, w.sequence, &column_family_memtables, &flush_scheduler_,
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&trim_history_scheduler_,
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write_options.ignore_missing_column_families, 0 /*log_number*/,
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this, true /*concurrent_memtable_writes*/, seq_per_batch_,
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w.batch_cnt, batch_per_txn_,
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write_options.memtable_insert_hint_per_batch);
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}
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}
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if (seq_used != nullptr) {
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*seq_used = w.sequence;
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}
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}
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}
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PERF_TIMER_START(write_pre_and_post_process_time);
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if (!w.CallbackFailed()) {
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WriteStatusCheck(status);
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}
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if (need_log_sync) {
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mutex_.Lock();
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MarkLogsSynced(logfile_number_, need_log_dir_sync, status);
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mutex_.Unlock();
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// Requesting sync with two_write_queues_ is expected to be very rare. We
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// hence provide a simple implementation that is not necessarily efficient.
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if (two_write_queues_) {
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if (manual_wal_flush_) {
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status = FlushWAL(true);
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} else {
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status = SyncWAL();
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}
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}
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}
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bool should_exit_batch_group = true;
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if (in_parallel_group) {
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// CompleteParallelWorker returns true if this thread should
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// handle exit, false means somebody else did
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should_exit_batch_group = write_thread_.CompleteParallelMemTableWriter(&w);
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}
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if (should_exit_batch_group) {
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if (status.ok()) {
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// Note: if we are to resume after non-OK statuses we need to revisit how
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// we reacts to non-OK statuses here.
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versions_->SetLastSequence(last_sequence);
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}
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MemTableInsertStatusCheck(w.status);
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write_thread_.ExitAsBatchGroupLeader(write_group, status);
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|
}
|
|
|
|
if (status.ok()) {
|
|
status = w.FinalStatus();
|
|
}
|
|
return status;
|
|
}
|
|
|
|
Status DBImpl::PipelinedWriteImpl(const WriteOptions& write_options,
|
|
WriteBatch* my_batch, WriteCallback* callback,
|
|
uint64_t* log_used, uint64_t log_ref,
|
|
bool disable_memtable, uint64_t* seq_used) {
|
|
PERF_TIMER_GUARD(write_pre_and_post_process_time);
|
|
StopWatch write_sw(env_, immutable_db_options_.statistics.get(), DB_WRITE);
|
|
|
|
WriteContext write_context;
|
|
|
|
WriteThread::Writer w(write_options, my_batch, callback, log_ref,
|
|
disable_memtable);
|
|
write_thread_.JoinBatchGroup(&w);
|
|
if (w.state == WriteThread::STATE_GROUP_LEADER) {
|
|
WriteThread::WriteGroup wal_write_group;
|
|
if (w.callback && !w.callback->AllowWriteBatching()) {
|
|
write_thread_.WaitForMemTableWriters();
|
|
}
|
|
mutex_.Lock();
|
|
bool need_log_sync = !write_options.disableWAL && write_options.sync;
|
|
bool need_log_dir_sync = need_log_sync && !log_dir_synced_;
|
|
// PreprocessWrite does its own perf timing.
|
|
PERF_TIMER_STOP(write_pre_and_post_process_time);
|
|
w.status = PreprocessWrite(write_options, &need_log_sync, &write_context);
|
|
PERF_TIMER_START(write_pre_and_post_process_time);
|
|
log::Writer* log_writer = logs_.back().writer;
|
|
mutex_.Unlock();
|
|
|
|
// This can set non-OK status if callback fail.
|
|
last_batch_group_size_ =
|
|
write_thread_.EnterAsBatchGroupLeader(&w, &wal_write_group);
|
|
const SequenceNumber current_sequence =
|
|
write_thread_.UpdateLastSequence(versions_->LastSequence()) + 1;
|
|
size_t total_count = 0;
|
|
size_t total_byte_size = 0;
|
|
|
|
if (w.status.ok()) {
|
|
SequenceNumber next_sequence = current_sequence;
|
|
for (auto writer : wal_write_group) {
|
|
if (writer->CheckCallback(this)) {
|
|
if (writer->ShouldWriteToMemtable()) {
|
|
writer->sequence = next_sequence;
|
|
size_t count = WriteBatchInternal::Count(writer->batch);
|
|
next_sequence += count;
|
|
total_count += count;
|
|
}
|
|
total_byte_size = WriteBatchInternal::AppendedByteSize(
|
|
total_byte_size, WriteBatchInternal::ByteSize(writer->batch));
|
|
}
|
|
}
|
|
if (w.disable_wal) {
|
|
has_unpersisted_data_.store(true, std::memory_order_relaxed);
|
|
}
|
|
write_thread_.UpdateLastSequence(current_sequence + total_count - 1);
|
|
}
|
|
|
|
auto stats = default_cf_internal_stats_;
|
|
stats->AddDBStats(InternalStats::kIntStatsNumKeysWritten, total_count);
|
|
RecordTick(stats_, NUMBER_KEYS_WRITTEN, total_count);
|
|
stats->AddDBStats(InternalStats::kIntStatsBytesWritten, total_byte_size);
|
|
RecordTick(stats_, BYTES_WRITTEN, total_byte_size);
|
|
RecordInHistogram(stats_, BYTES_PER_WRITE, total_byte_size);
|
|
|
|
PERF_TIMER_STOP(write_pre_and_post_process_time);
|
|
|
|
if (w.status.ok() && !write_options.disableWAL) {
|
|
PERF_TIMER_GUARD(write_wal_time);
|
|
stats->AddDBStats(InternalStats::kIntStatsWriteDoneBySelf, 1);
|
|
RecordTick(stats_, WRITE_DONE_BY_SELF, 1);
|
|
if (wal_write_group.size > 1) {
|
|
stats->AddDBStats(InternalStats::kIntStatsWriteDoneByOther,
|
|
wal_write_group.size - 1);
|
|
RecordTick(stats_, WRITE_DONE_BY_OTHER, wal_write_group.size - 1);
|
|
}
|
|
w.status = WriteToWAL(wal_write_group, log_writer, log_used,
|
|
need_log_sync, need_log_dir_sync, current_sequence);
|
|
}
|
|
|
|
if (!w.CallbackFailed()) {
|
|
WriteStatusCheck(w.status);
|
|
}
|
|
|
|
if (need_log_sync) {
|
|
mutex_.Lock();
|
|
MarkLogsSynced(logfile_number_, need_log_dir_sync, w.status);
|
|
mutex_.Unlock();
|
|
}
|
|
|
|
write_thread_.ExitAsBatchGroupLeader(wal_write_group, w.status);
|
|
}
|
|
|
|
WriteThread::WriteGroup memtable_write_group;
|
|
if (w.state == WriteThread::STATE_MEMTABLE_WRITER_LEADER) {
|
|
PERF_TIMER_GUARD(write_memtable_time);
|
|
assert(w.ShouldWriteToMemtable());
|
|
write_thread_.EnterAsMemTableWriter(&w, &memtable_write_group);
|
|
if (memtable_write_group.size > 1 &&
|
|
immutable_db_options_.allow_concurrent_memtable_write) {
|
|
write_thread_.LaunchParallelMemTableWriters(&memtable_write_group);
|
|
} else {
|
|
memtable_write_group.status = WriteBatchInternal::InsertInto(
|
|
memtable_write_group, w.sequence, column_family_memtables_.get(),
|
|
&flush_scheduler_, &trim_history_scheduler_,
|
|
write_options.ignore_missing_column_families, 0 /*log_number*/, this,
|
|
false /*concurrent_memtable_writes*/, seq_per_batch_, batch_per_txn_);
|
|
versions_->SetLastSequence(memtable_write_group.last_sequence);
|
|
write_thread_.ExitAsMemTableWriter(&w, memtable_write_group);
|
|
}
|
|
}
|
|
|
|
if (w.state == WriteThread::STATE_PARALLEL_MEMTABLE_WRITER) {
|
|
assert(w.ShouldWriteToMemtable());
|
|
ColumnFamilyMemTablesImpl column_family_memtables(
|
|
versions_->GetColumnFamilySet());
|
|
w.status = WriteBatchInternal::InsertInto(
|
|
&w, w.sequence, &column_family_memtables, &flush_scheduler_,
|
|
&trim_history_scheduler_, write_options.ignore_missing_column_families,
|
|
0 /*log_number*/, this, true /*concurrent_memtable_writes*/,
|
|
false /*seq_per_batch*/, 0 /*batch_cnt*/, true /*batch_per_txn*/,
|
|
write_options.memtable_insert_hint_per_batch);
|
|
if (write_thread_.CompleteParallelMemTableWriter(&w)) {
|
|
MemTableInsertStatusCheck(w.status);
|
|
versions_->SetLastSequence(w.write_group->last_sequence);
|
|
write_thread_.ExitAsMemTableWriter(&w, *w.write_group);
|
|
}
|
|
}
|
|
if (seq_used != nullptr) {
|
|
*seq_used = w.sequence;
|
|
}
|
|
|
|
assert(w.state == WriteThread::STATE_COMPLETED);
|
|
return w.FinalStatus();
|
|
}
|
|
|
|
Status DBImpl::UnorderedWriteMemtable(const WriteOptions& write_options,
|
|
WriteBatch* my_batch,
|
|
WriteCallback* callback, uint64_t log_ref,
|
|
SequenceNumber seq,
|
|
const size_t sub_batch_cnt) {
|
|
PERF_TIMER_GUARD(write_pre_and_post_process_time);
|
|
StopWatch write_sw(env_, immutable_db_options_.statistics.get(), DB_WRITE);
|
|
|
|
WriteThread::Writer w(write_options, my_batch, callback, log_ref,
|
|
false /*disable_memtable*/);
|
|
|
|
if (w.CheckCallback(this) && w.ShouldWriteToMemtable()) {
|
|
w.sequence = seq;
|
|
size_t total_count = WriteBatchInternal::Count(my_batch);
|
|
InternalStats* stats = default_cf_internal_stats_;
|
|
stats->AddDBStats(InternalStats::kIntStatsNumKeysWritten, total_count);
|
|
RecordTick(stats_, NUMBER_KEYS_WRITTEN, total_count);
|
|
|
|
ColumnFamilyMemTablesImpl column_family_memtables(
|
|
versions_->GetColumnFamilySet());
|
|
w.status = WriteBatchInternal::InsertInto(
|
|
&w, w.sequence, &column_family_memtables, &flush_scheduler_,
|
|
&trim_history_scheduler_, write_options.ignore_missing_column_families,
|
|
0 /*log_number*/, this, true /*concurrent_memtable_writes*/,
|
|
seq_per_batch_, sub_batch_cnt, true /*batch_per_txn*/,
|
|
write_options.memtable_insert_hint_per_batch);
|
|
|
|
WriteStatusCheck(w.status);
|
|
if (write_options.disableWAL) {
|
|
has_unpersisted_data_.store(true, std::memory_order_relaxed);
|
|
}
|
|
}
|
|
|
|
size_t pending_cnt = pending_memtable_writes_.fetch_sub(1) - 1;
|
|
if (pending_cnt == 0) {
|
|
// switch_cv_ waits until pending_memtable_writes_ = 0. Locking its mutex
|
|
// before notify ensures that cv is in waiting state when it is notified
|
|
// thus not missing the update to pending_memtable_writes_ even though it is
|
|
// not modified under the mutex.
|
|
std::lock_guard<std::mutex> lck(switch_mutex_);
|
|
switch_cv_.notify_all();
|
|
}
|
|
|
|
if (!w.FinalStatus().ok()) {
|
|
return w.FinalStatus();
|
|
}
|
|
return Status::OK();
|
|
}
|
|
|
|
// The 2nd write queue. If enabled it will be used only for WAL-only writes.
|
|
// This is the only queue that updates LastPublishedSequence which is only
|
|
// applicable in a two-queue setting.
|
|
Status DBImpl::WriteImplWALOnly(
|
|
WriteThread* write_thread, const WriteOptions& write_options,
|
|
WriteBatch* my_batch, WriteCallback* callback, uint64_t* log_used,
|
|
const uint64_t log_ref, uint64_t* seq_used, const size_t sub_batch_cnt,
|
|
PreReleaseCallback* pre_release_callback, const AssignOrder assign_order,
|
|
const PublishLastSeq publish_last_seq, const bool disable_memtable) {
|
|
Status status;
|
|
PERF_TIMER_GUARD(write_pre_and_post_process_time);
|
|
WriteThread::Writer w(write_options, my_batch, callback, log_ref,
|
|
disable_memtable, sub_batch_cnt, pre_release_callback);
|
|
RecordTick(stats_, WRITE_WITH_WAL);
|
|
StopWatch write_sw(env_, immutable_db_options_.statistics.get(), DB_WRITE);
|
|
|
|
write_thread->JoinBatchGroup(&w);
|
|
assert(w.state != WriteThread::STATE_PARALLEL_MEMTABLE_WRITER);
|
|
if (w.state == WriteThread::STATE_COMPLETED) {
|
|
if (log_used != nullptr) {
|
|
*log_used = w.log_used;
|
|
}
|
|
if (seq_used != nullptr) {
|
|
*seq_used = w.sequence;
|
|
}
|
|
return w.FinalStatus();
|
|
}
|
|
// else we are the leader of the write batch group
|
|
assert(w.state == WriteThread::STATE_GROUP_LEADER);
|
|
|
|
if (publish_last_seq == kDoPublishLastSeq) {
|
|
// Currently we only use kDoPublishLastSeq in unordered_write
|
|
assert(immutable_db_options_.unordered_write);
|
|
WriteContext write_context;
|
|
if (error_handler_.IsDBStopped()) {
|
|
status = error_handler_.GetBGError();
|
|
}
|
|
// TODO(myabandeh): Make preliminary checks thread-safe so we could do them
|
|
// without paying the cost of obtaining the mutex.
|
|
if (status.ok()) {
|
|
InstrumentedMutexLock l(&mutex_);
|
|
bool need_log_sync = false;
|
|
status = PreprocessWrite(write_options, &need_log_sync, &write_context);
|
|
WriteStatusCheck(status);
|
|
}
|
|
if (!status.ok()) {
|
|
WriteThread::WriteGroup write_group;
|
|
write_thread->EnterAsBatchGroupLeader(&w, &write_group);
|
|
write_thread->ExitAsBatchGroupLeader(write_group, status);
|
|
return status;
|
|
}
|
|
}
|
|
|
|
WriteThread::WriteGroup write_group;
|
|
uint64_t last_sequence;
|
|
write_thread->EnterAsBatchGroupLeader(&w, &write_group);
|
|
// Note: no need to update last_batch_group_size_ here since the batch writes
|
|
// to WAL only
|
|
|
|
size_t pre_release_callback_cnt = 0;
|
|
size_t total_byte_size = 0;
|
|
for (auto* writer : write_group) {
|
|
if (writer->CheckCallback(this)) {
|
|
total_byte_size = WriteBatchInternal::AppendedByteSize(
|
|
total_byte_size, WriteBatchInternal::ByteSize(writer->batch));
|
|
if (writer->pre_release_callback) {
|
|
pre_release_callback_cnt++;
|
|
}
|
|
}
|
|
}
|
|
|
|
const bool concurrent_update = true;
|
|
// Update stats while we are an exclusive group leader, so we know
|
|
// that nobody else can be writing to these particular stats.
|
|
// We're optimistic, updating the stats before we successfully
|
|
// commit. That lets us release our leader status early.
|
|
auto stats = default_cf_internal_stats_;
|
|
stats->AddDBStats(InternalStats::kIntStatsBytesWritten, total_byte_size,
|
|
concurrent_update);
|
|
RecordTick(stats_, BYTES_WRITTEN, total_byte_size);
|
|
stats->AddDBStats(InternalStats::kIntStatsWriteDoneBySelf, 1,
|
|
concurrent_update);
|
|
RecordTick(stats_, WRITE_DONE_BY_SELF);
|
|
auto write_done_by_other = write_group.size - 1;
|
|
if (write_done_by_other > 0) {
|
|
stats->AddDBStats(InternalStats::kIntStatsWriteDoneByOther,
|
|
write_done_by_other, concurrent_update);
|
|
RecordTick(stats_, WRITE_DONE_BY_OTHER, write_done_by_other);
|
|
}
|
|
RecordInHistogram(stats_, BYTES_PER_WRITE, total_byte_size);
|
|
|
|
PERF_TIMER_STOP(write_pre_and_post_process_time);
|
|
|
|
PERF_TIMER_GUARD(write_wal_time);
|
|
// LastAllocatedSequence is increased inside WriteToWAL under
|
|
// wal_write_mutex_ to ensure ordered events in WAL
|
|
size_t seq_inc = 0 /* total_count */;
|
|
if (assign_order == kDoAssignOrder) {
|
|
size_t total_batch_cnt = 0;
|
|
for (auto* writer : write_group) {
|
|
assert(writer->batch_cnt || !seq_per_batch_);
|
|
if (!writer->CallbackFailed()) {
|
|
total_batch_cnt += writer->batch_cnt;
|
|
}
|
|
}
|
|
seq_inc = total_batch_cnt;
|
|
}
|
|
if (!write_options.disableWAL) {
|
|
status =
|
|
ConcurrentWriteToWAL(write_group, log_used, &last_sequence, seq_inc);
|
|
} else {
|
|
// Otherwise we inc seq number to do solely the seq allocation
|
|
last_sequence = versions_->FetchAddLastAllocatedSequence(seq_inc);
|
|
}
|
|
|
|
size_t memtable_write_cnt = 0;
|
|
auto curr_seq = last_sequence + 1;
|
|
for (auto* writer : write_group) {
|
|
if (writer->CallbackFailed()) {
|
|
continue;
|
|
}
|
|
writer->sequence = curr_seq;
|
|
if (assign_order == kDoAssignOrder) {
|
|
assert(writer->batch_cnt || !seq_per_batch_);
|
|
curr_seq += writer->batch_cnt;
|
|
}
|
|
if (!writer->disable_memtable) {
|
|
memtable_write_cnt++;
|
|
}
|
|
// else seq advances only by memtable writes
|
|
}
|
|
if (status.ok() && write_options.sync) {
|
|
assert(!write_options.disableWAL);
|
|
// Requesting sync with two_write_queues_ is expected to be very rare. We
|
|
// hance provide a simple implementation that is not necessarily efficient.
|
|
if (manual_wal_flush_) {
|
|
status = FlushWAL(true);
|
|
} else {
|
|
status = SyncWAL();
|
|
}
|
|
}
|
|
PERF_TIMER_START(write_pre_and_post_process_time);
|
|
|
|
if (!w.CallbackFailed()) {
|
|
WriteStatusCheck(status);
|
|
}
|
|
if (status.ok()) {
|
|
size_t index = 0;
|
|
for (auto* writer : write_group) {
|
|
if (!writer->CallbackFailed() && writer->pre_release_callback) {
|
|
assert(writer->sequence != kMaxSequenceNumber);
|
|
Status ws = writer->pre_release_callback->Callback(
|
|
writer->sequence, disable_memtable, writer->log_used, index++,
|
|
pre_release_callback_cnt);
|
|
if (!ws.ok()) {
|
|
status = ws;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
if (publish_last_seq == kDoPublishLastSeq) {
|
|
versions_->SetLastSequence(last_sequence + seq_inc);
|
|
// Currently we only use kDoPublishLastSeq in unordered_write
|
|
assert(immutable_db_options_.unordered_write);
|
|
}
|
|
if (immutable_db_options_.unordered_write && status.ok()) {
|
|
pending_memtable_writes_ += memtable_write_cnt;
|
|
}
|
|
write_thread->ExitAsBatchGroupLeader(write_group, status);
|
|
if (status.ok()) {
|
|
status = w.FinalStatus();
|
|
}
|
|
if (seq_used != nullptr) {
|
|
*seq_used = w.sequence;
|
|
}
|
|
return status;
|
|
}
|
|
|
|
void DBImpl::WriteStatusCheck(const Status& status) {
|
|
// Is setting bg_error_ enough here? This will at least stop
|
|
// compaction and fail any further writes.
|
|
if (immutable_db_options_.paranoid_checks && !status.ok() &&
|
|
!status.IsBusy() && !status.IsIncomplete()) {
|
|
mutex_.Lock();
|
|
error_handler_.SetBGError(status, BackgroundErrorReason::kWriteCallback);
|
|
mutex_.Unlock();
|
|
}
|
|
}
|
|
|
|
void DBImpl::MemTableInsertStatusCheck(const Status& status) {
|
|
// A non-OK status here indicates that the state implied by the
|
|
// WAL has diverged from the in-memory state. This could be
|
|
// because of a corrupt write_batch (very bad), or because the
|
|
// client specified an invalid column family and didn't specify
|
|
// ignore_missing_column_families.
|
|
if (!status.ok()) {
|
|
mutex_.Lock();
|
|
assert(!error_handler_.IsBGWorkStopped());
|
|
error_handler_.SetBGError(status, BackgroundErrorReason::kMemTable);
|
|
mutex_.Unlock();
|
|
}
|
|
}
|
|
|
|
Status DBImpl::PreprocessWrite(const WriteOptions& write_options,
|
|
bool* need_log_sync,
|
|
WriteContext* write_context) {
|
|
mutex_.AssertHeld();
|
|
assert(write_context != nullptr && need_log_sync != nullptr);
|
|
Status status;
|
|
|
|
if (error_handler_.IsDBStopped()) {
|
|
status = error_handler_.GetBGError();
|
|
}
|
|
|
|
PERF_TIMER_GUARD(write_scheduling_flushes_compactions_time);
|
|
|
|
assert(!single_column_family_mode_ ||
|
|
versions_->GetColumnFamilySet()->NumberOfColumnFamilies() == 1);
|
|
if (UNLIKELY(status.ok() && !single_column_family_mode_ &&
|
|
total_log_size_ > GetMaxTotalWalSize())) {
|
|
WaitForPendingWrites();
|
|
status = SwitchWAL(write_context);
|
|
}
|
|
|
|
if (UNLIKELY(status.ok() && write_buffer_manager_->ShouldFlush())) {
|
|
// Before a new memtable is added in SwitchMemtable(),
|
|
// write_buffer_manager_->ShouldFlush() will keep returning true. If another
|
|
// thread is writing to another DB with the same write buffer, they may also
|
|
// be flushed. We may end up with flushing much more DBs than needed. It's
|
|
// suboptimal but still correct.
|
|
WaitForPendingWrites();
|
|
status = HandleWriteBufferFull(write_context);
|
|
}
|
|
|
|
if (UNLIKELY(status.ok() && !trim_history_scheduler_.Empty())) {
|
|
status = TrimMemtableHistory(write_context);
|
|
}
|
|
|
|
if (UNLIKELY(status.ok() && !flush_scheduler_.Empty())) {
|
|
WaitForPendingWrites();
|
|
status = ScheduleFlushes(write_context);
|
|
}
|
|
|
|
PERF_TIMER_STOP(write_scheduling_flushes_compactions_time);
|
|
PERF_TIMER_GUARD(write_pre_and_post_process_time);
|
|
|
|
if (UNLIKELY(status.ok() && (write_controller_.IsStopped() ||
|
|
write_controller_.NeedsDelay()))) {
|
|
PERF_TIMER_STOP(write_pre_and_post_process_time);
|
|
PERF_TIMER_GUARD(write_delay_time);
|
|
// We don't know size of curent batch so that we always use the size
|
|
// for previous one. It might create a fairness issue that expiration
|
|
// might happen for smaller writes but larger writes can go through.
|
|
// Can optimize it if it is an issue.
|
|
status = DelayWrite(last_batch_group_size_, write_options);
|
|
PERF_TIMER_START(write_pre_and_post_process_time);
|
|
}
|
|
|
|
if (status.ok() && *need_log_sync) {
|
|
// Wait until the parallel syncs are finished. Any sync process has to sync
|
|
// the front log too so it is enough to check the status of front()
|
|
// We do a while loop since log_sync_cv_ is signalled when any sync is
|
|
// finished
|
|
// Note: there does not seem to be a reason to wait for parallel sync at
|
|
// this early step but it is not important since parallel sync (SyncWAL) and
|
|
// need_log_sync are usually not used together.
|
|
while (logs_.front().getting_synced) {
|
|
log_sync_cv_.Wait();
|
|
}
|
|
for (auto& log : logs_) {
|
|
assert(!log.getting_synced);
|
|
// This is just to prevent the logs to be synced by a parallel SyncWAL
|
|
// call. We will do the actual syncing later after we will write to the
|
|
// WAL.
|
|
// Note: there does not seem to be a reason to set this early before we
|
|
// actually write to the WAL
|
|
log.getting_synced = true;
|
|
}
|
|
} else {
|
|
*need_log_sync = false;
|
|
}
|
|
|
|
return status;
|
|
}
|
|
|
|
WriteBatch* DBImpl::MergeBatch(const WriteThread::WriteGroup& write_group,
|
|
WriteBatch* tmp_batch, size_t* write_with_wal,
|
|
WriteBatch** to_be_cached_state) {
|
|
assert(write_with_wal != nullptr);
|
|
assert(tmp_batch != nullptr);
|
|
assert(*to_be_cached_state == nullptr);
|
|
WriteBatch* merged_batch = nullptr;
|
|
*write_with_wal = 0;
|
|
auto* leader = write_group.leader;
|
|
assert(!leader->disable_wal); // Same holds for all in the batch group
|
|
if (write_group.size == 1 && !leader->CallbackFailed() &&
|
|
leader->batch->GetWalTerminationPoint().is_cleared()) {
|
|
// we simply write the first WriteBatch to WAL if the group only
|
|
// contains one batch, that batch should be written to the WAL,
|
|
// and the batch is not wanting to be truncated
|
|
merged_batch = leader->batch;
|
|
if (WriteBatchInternal::IsLatestPersistentState(merged_batch)) {
|
|
*to_be_cached_state = merged_batch;
|
|
}
|
|
*write_with_wal = 1;
|
|
} else {
|
|
// WAL needs all of the batches flattened into a single batch.
|
|
// We could avoid copying here with an iov-like AddRecord
|
|
// interface
|
|
merged_batch = tmp_batch;
|
|
for (auto writer : write_group) {
|
|
if (!writer->CallbackFailed()) {
|
|
WriteBatchInternal::Append(merged_batch, writer->batch,
|
|
/*WAL_only*/ true);
|
|
if (WriteBatchInternal::IsLatestPersistentState(writer->batch)) {
|
|
// We only need to cache the last of such write batch
|
|
*to_be_cached_state = writer->batch;
|
|
}
|
|
(*write_with_wal)++;
|
|
}
|
|
}
|
|
}
|
|
return merged_batch;
|
|
}
|
|
|
|
// When two_write_queues_ is disabled, this function is called from the only
|
|
// write thread. Otherwise this must be called holding log_write_mutex_.
|
|
Status DBImpl::WriteToWAL(const WriteBatch& merged_batch,
|
|
log::Writer* log_writer, uint64_t* log_used,
|
|
uint64_t* log_size) {
|
|
assert(log_size != nullptr);
|
|
Slice log_entry = WriteBatchInternal::Contents(&merged_batch);
|
|
*log_size = log_entry.size();
|
|
// When two_write_queues_ WriteToWAL has to be protected from concurretn calls
|
|
// from the two queues anyway and log_write_mutex_ is already held. Otherwise
|
|
// if manual_wal_flush_ is enabled we need to protect log_writer->AddRecord
|
|
// from possible concurrent calls via the FlushWAL by the application.
|
|
const bool needs_locking = manual_wal_flush_ && !two_write_queues_;
|
|
// Due to performance cocerns of missed branch prediction penalize the new
|
|
// manual_wal_flush_ feature (by UNLIKELY) instead of the more common case
|
|
// when we do not need any locking.
|
|
if (UNLIKELY(needs_locking)) {
|
|
log_write_mutex_.Lock();
|
|
}
|
|
Status status = log_writer->AddRecord(log_entry);
|
|
if (UNLIKELY(needs_locking)) {
|
|
log_write_mutex_.Unlock();
|
|
}
|
|
if (log_used != nullptr) {
|
|
*log_used = logfile_number_;
|
|
}
|
|
total_log_size_ += log_entry.size();
|
|
// TODO(myabandeh): it might be unsafe to access alive_log_files_.back() here
|
|
// since alive_log_files_ might be modified concurrently
|
|
alive_log_files_.back().AddSize(log_entry.size());
|
|
log_empty_ = false;
|
|
return status;
|
|
}
|
|
|
|
Status DBImpl::WriteToWAL(const WriteThread::WriteGroup& write_group,
|
|
log::Writer* log_writer, uint64_t* log_used,
|
|
bool need_log_sync, bool need_log_dir_sync,
|
|
SequenceNumber sequence) {
|
|
Status status;
|
|
|
|
assert(!write_group.leader->disable_wal);
|
|
// Same holds for all in the batch group
|
|
size_t write_with_wal = 0;
|
|
WriteBatch* to_be_cached_state = nullptr;
|
|
WriteBatch* merged_batch = MergeBatch(write_group, &tmp_batch_,
|
|
&write_with_wal, &to_be_cached_state);
|
|
if (merged_batch == write_group.leader->batch) {
|
|
write_group.leader->log_used = logfile_number_;
|
|
} else if (write_with_wal > 1) {
|
|
for (auto writer : write_group) {
|
|
writer->log_used = logfile_number_;
|
|
}
|
|
}
|
|
|
|
WriteBatchInternal::SetSequence(merged_batch, sequence);
|
|
|
|
uint64_t log_size;
|
|
status = WriteToWAL(*merged_batch, log_writer, log_used, &log_size);
|
|
if (to_be_cached_state) {
|
|
cached_recoverable_state_ = *to_be_cached_state;
|
|
cached_recoverable_state_empty_ = false;
|
|
}
|
|
|
|
if (status.ok() && need_log_sync) {
|
|
StopWatch sw(env_, stats_, WAL_FILE_SYNC_MICROS);
|
|
// It's safe to access logs_ with unlocked mutex_ here because:
|
|
// - we've set getting_synced=true for all logs,
|
|
// so other threads won't pop from logs_ while we're here,
|
|
// - only writer thread can push to logs_, and we're in
|
|
// writer thread, so no one will push to logs_,
|
|
// - as long as other threads don't modify it, it's safe to read
|
|
// from std::deque from multiple threads concurrently.
|
|
for (auto& log : logs_) {
|
|
status = log.writer->file()->Sync(immutable_db_options_.use_fsync);
|
|
if (!status.ok()) {
|
|
break;
|
|
}
|
|
}
|
|
if (status.ok() && need_log_dir_sync) {
|
|
// We only sync WAL directory the first time WAL syncing is
|
|
// requested, so that in case users never turn on WAL sync,
|
|
// we can avoid the disk I/O in the write code path.
|
|
status = directories_.GetWalDir()->Fsync();
|
|
}
|
|
}
|
|
|
|
if (merged_batch == &tmp_batch_) {
|
|
tmp_batch_.Clear();
|
|
}
|
|
if (status.ok()) {
|
|
auto stats = default_cf_internal_stats_;
|
|
if (need_log_sync) {
|
|
stats->AddDBStats(InternalStats::kIntStatsWalFileSynced, 1);
|
|
RecordTick(stats_, WAL_FILE_SYNCED);
|
|
}
|
|
stats->AddDBStats(InternalStats::kIntStatsWalFileBytes, log_size);
|
|
RecordTick(stats_, WAL_FILE_BYTES, log_size);
|
|
stats->AddDBStats(InternalStats::kIntStatsWriteWithWal, write_with_wal);
|
|
RecordTick(stats_, WRITE_WITH_WAL, write_with_wal);
|
|
}
|
|
return status;
|
|
}
|
|
|
|
Status DBImpl::ConcurrentWriteToWAL(const WriteThread::WriteGroup& write_group,
|
|
uint64_t* log_used,
|
|
SequenceNumber* last_sequence,
|
|
size_t seq_inc) {
|
|
Status status;
|
|
|
|
assert(!write_group.leader->disable_wal);
|
|
// Same holds for all in the batch group
|
|
WriteBatch tmp_batch;
|
|
size_t write_with_wal = 0;
|
|
WriteBatch* to_be_cached_state = nullptr;
|
|
WriteBatch* merged_batch =
|
|
MergeBatch(write_group, &tmp_batch, &write_with_wal, &to_be_cached_state);
|
|
|
|
// We need to lock log_write_mutex_ since logs_ and alive_log_files might be
|
|
// pushed back concurrently
|
|
log_write_mutex_.Lock();
|
|
if (merged_batch == write_group.leader->batch) {
|
|
write_group.leader->log_used = logfile_number_;
|
|
} else if (write_with_wal > 1) {
|
|
for (auto writer : write_group) {
|
|
writer->log_used = logfile_number_;
|
|
}
|
|
}
|
|
*last_sequence = versions_->FetchAddLastAllocatedSequence(seq_inc);
|
|
auto sequence = *last_sequence + 1;
|
|
WriteBatchInternal::SetSequence(merged_batch, sequence);
|
|
|
|
log::Writer* log_writer = logs_.back().writer;
|
|
uint64_t log_size;
|
|
status = WriteToWAL(*merged_batch, log_writer, log_used, &log_size);
|
|
if (to_be_cached_state) {
|
|
cached_recoverable_state_ = *to_be_cached_state;
|
|
cached_recoverable_state_empty_ = false;
|
|
}
|
|
log_write_mutex_.Unlock();
|
|
|
|
if (status.ok()) {
|
|
const bool concurrent = true;
|
|
auto stats = default_cf_internal_stats_;
|
|
stats->AddDBStats(InternalStats::kIntStatsWalFileBytes, log_size,
|
|
concurrent);
|
|
RecordTick(stats_, WAL_FILE_BYTES, log_size);
|
|
stats->AddDBStats(InternalStats::kIntStatsWriteWithWal, write_with_wal,
|
|
concurrent);
|
|
RecordTick(stats_, WRITE_WITH_WAL, write_with_wal);
|
|
}
|
|
return status;
|
|
}
|
|
|
|
Status DBImpl::WriteRecoverableState() {
|
|
mutex_.AssertHeld();
|
|
if (!cached_recoverable_state_empty_) {
|
|
bool dont_care_bool;
|
|
SequenceNumber next_seq;
|
|
if (two_write_queues_) {
|
|
log_write_mutex_.Lock();
|
|
}
|
|
SequenceNumber seq;
|
|
if (two_write_queues_) {
|
|
seq = versions_->FetchAddLastAllocatedSequence(0);
|
|
} else {
|
|
seq = versions_->LastSequence();
|
|
}
|
|
WriteBatchInternal::SetSequence(&cached_recoverable_state_, seq + 1);
|
|
auto status = WriteBatchInternal::InsertInto(
|
|
&cached_recoverable_state_, column_family_memtables_.get(),
|
|
&flush_scheduler_, &trim_history_scheduler_, true,
|
|
0 /*recovery_log_number*/, this, false /* concurrent_memtable_writes */,
|
|
&next_seq, &dont_care_bool, seq_per_batch_);
|
|
auto last_seq = next_seq - 1;
|
|
if (two_write_queues_) {
|
|
versions_->FetchAddLastAllocatedSequence(last_seq - seq);
|
|
versions_->SetLastPublishedSequence(last_seq);
|
|
}
|
|
versions_->SetLastSequence(last_seq);
|
|
if (two_write_queues_) {
|
|
log_write_mutex_.Unlock();
|
|
}
|
|
if (status.ok() && recoverable_state_pre_release_callback_) {
|
|
const bool DISABLE_MEMTABLE = true;
|
|
for (uint64_t sub_batch_seq = seq + 1;
|
|
sub_batch_seq < next_seq && status.ok(); sub_batch_seq++) {
|
|
uint64_t const no_log_num = 0;
|
|
// Unlock it since the callback might end up locking mutex. e.g.,
|
|
// AddCommitted -> AdvanceMaxEvictedSeq -> GetSnapshotListFromDB
|
|
mutex_.Unlock();
|
|
status = recoverable_state_pre_release_callback_->Callback(
|
|
sub_batch_seq, !DISABLE_MEMTABLE, no_log_num, 0, 1);
|
|
mutex_.Lock();
|
|
}
|
|
}
|
|
if (status.ok()) {
|
|
cached_recoverable_state_.Clear();
|
|
cached_recoverable_state_empty_ = true;
|
|
}
|
|
return status;
|
|
}
|
|
return Status::OK();
|
|
}
|
|
|
|
void DBImpl::SelectColumnFamiliesForAtomicFlush(
|
|
autovector<ColumnFamilyData*>* cfds) {
|
|
for (ColumnFamilyData* cfd : *versions_->GetColumnFamilySet()) {
|
|
if (cfd->IsDropped()) {
|
|
continue;
|
|
}
|
|
if (cfd->imm()->NumNotFlushed() != 0 || !cfd->mem()->IsEmpty() ||
|
|
!cached_recoverable_state_empty_.load()) {
|
|
cfds->push_back(cfd);
|
|
}
|
|
}
|
|
}
|
|
|
|
// Assign sequence number for atomic flush.
|
|
void DBImpl::AssignAtomicFlushSeq(const autovector<ColumnFamilyData*>& cfds) {
|
|
assert(immutable_db_options_.atomic_flush);
|
|
auto seq = versions_->LastSequence();
|
|
for (auto cfd : cfds) {
|
|
cfd->imm()->AssignAtomicFlushSeq(seq);
|
|
}
|
|
}
|
|
|
|
Status DBImpl::SwitchWAL(WriteContext* write_context) {
|
|
mutex_.AssertHeld();
|
|
assert(write_context != nullptr);
|
|
Status status;
|
|
|
|
if (alive_log_files_.begin()->getting_flushed) {
|
|
return status;
|
|
}
|
|
|
|
auto oldest_alive_log = alive_log_files_.begin()->number;
|
|
bool flush_wont_release_oldest_log = false;
|
|
if (allow_2pc()) {
|
|
auto oldest_log_with_uncommitted_prep =
|
|
logs_with_prep_tracker_.FindMinLogContainingOutstandingPrep();
|
|
|
|
assert(oldest_log_with_uncommitted_prep == 0 ||
|
|
oldest_log_with_uncommitted_prep >= oldest_alive_log);
|
|
if (oldest_log_with_uncommitted_prep > 0 &&
|
|
oldest_log_with_uncommitted_prep == oldest_alive_log) {
|
|
if (unable_to_release_oldest_log_) {
|
|
// we already attempted to flush all column families dependent on
|
|
// the oldest alive log but the log still contained uncommitted
|
|
// transactions so there is still nothing that we can do.
|
|
return status;
|
|
} else {
|
|
ROCKS_LOG_WARN(
|
|
immutable_db_options_.info_log,
|
|
"Unable to release oldest log due to uncommitted transaction");
|
|
unable_to_release_oldest_log_ = true;
|
|
flush_wont_release_oldest_log = true;
|
|
}
|
|
}
|
|
}
|
|
if (!flush_wont_release_oldest_log) {
|
|
// we only mark this log as getting flushed if we have successfully
|
|
// flushed all data in this log. If this log contains outstanding prepared
|
|
// transactions then we cannot flush this log until those transactions are
|
|
// commited.
|
|
unable_to_release_oldest_log_ = false;
|
|
alive_log_files_.begin()->getting_flushed = true;
|
|
}
|
|
|
|
ROCKS_LOG_INFO(
|
|
immutable_db_options_.info_log,
|
|
"Flushing all column families with data in WAL number %" PRIu64
|
|
". Total log size is %" PRIu64 " while max_total_wal_size is %" PRIu64,
|
|
oldest_alive_log, total_log_size_.load(), GetMaxTotalWalSize());
|
|
// no need to refcount because drop is happening in write thread, so can't
|
|
// happen while we're in the write thread
|
|
autovector<ColumnFamilyData*> cfds;
|
|
if (immutable_db_options_.atomic_flush) {
|
|
SelectColumnFamiliesForAtomicFlush(&cfds);
|
|
} else {
|
|
for (auto cfd : *versions_->GetColumnFamilySet()) {
|
|
if (cfd->IsDropped()) {
|
|
continue;
|
|
}
|
|
if (cfd->OldestLogToKeep() <= oldest_alive_log) {
|
|
cfds.push_back(cfd);
|
|
}
|
|
}
|
|
MaybeFlushStatsCF(&cfds);
|
|
}
|
|
WriteThread::Writer nonmem_w;
|
|
if (two_write_queues_) {
|
|
nonmem_write_thread_.EnterUnbatched(&nonmem_w, &mutex_);
|
|
}
|
|
|
|
for (const auto cfd : cfds) {
|
|
cfd->Ref();
|
|
status = SwitchMemtable(cfd, write_context);
|
|
cfd->Unref();
|
|
if (!status.ok()) {
|
|
break;
|
|
}
|
|
}
|
|
if (two_write_queues_) {
|
|
nonmem_write_thread_.ExitUnbatched(&nonmem_w);
|
|
}
|
|
|
|
if (status.ok()) {
|
|
if (immutable_db_options_.atomic_flush) {
|
|
AssignAtomicFlushSeq(cfds);
|
|
}
|
|
for (auto cfd : cfds) {
|
|
cfd->imm()->FlushRequested();
|
|
}
|
|
FlushRequest flush_req;
|
|
GenerateFlushRequest(cfds, &flush_req);
|
|
SchedulePendingFlush(flush_req, FlushReason::kWriteBufferManager);
|
|
MaybeScheduleFlushOrCompaction();
|
|
}
|
|
return status;
|
|
}
|
|
|
|
Status DBImpl::HandleWriteBufferFull(WriteContext* write_context) {
|
|
mutex_.AssertHeld();
|
|
assert(write_context != nullptr);
|
|
Status status;
|
|
|
|
// Before a new memtable is added in SwitchMemtable(),
|
|
// write_buffer_manager_->ShouldFlush() will keep returning true. If another
|
|
// thread is writing to another DB with the same write buffer, they may also
|
|
// be flushed. We may end up with flushing much more DBs than needed. It's
|
|
// suboptimal but still correct.
|
|
ROCKS_LOG_INFO(
|
|
immutable_db_options_.info_log,
|
|
"Flushing column family with largest mem table size. Write buffer is "
|
|
"using %" ROCKSDB_PRIszt " bytes out of a total of %" ROCKSDB_PRIszt ".",
|
|
write_buffer_manager_->memory_usage(),
|
|
write_buffer_manager_->buffer_size());
|
|
// no need to refcount because drop is happening in write thread, so can't
|
|
// happen while we're in the write thread
|
|
autovector<ColumnFamilyData*> cfds;
|
|
if (immutable_db_options_.atomic_flush) {
|
|
SelectColumnFamiliesForAtomicFlush(&cfds);
|
|
} else {
|
|
ColumnFamilyData* cfd_picked = nullptr;
|
|
SequenceNumber seq_num_for_cf_picked = kMaxSequenceNumber;
|
|
|
|
for (auto cfd : *versions_->GetColumnFamilySet()) {
|
|
if (cfd->IsDropped()) {
|
|
continue;
|
|
}
|
|
if (!cfd->mem()->IsEmpty()) {
|
|
// We only consider active mem table, hoping immutable memtable is
|
|
// already in the process of flushing.
|
|
uint64_t seq = cfd->mem()->GetCreationSeq();
|
|
if (cfd_picked == nullptr || seq < seq_num_for_cf_picked) {
|
|
cfd_picked = cfd;
|
|
seq_num_for_cf_picked = seq;
|
|
}
|
|
}
|
|
}
|
|
if (cfd_picked != nullptr) {
|
|
cfds.push_back(cfd_picked);
|
|
}
|
|
MaybeFlushStatsCF(&cfds);
|
|
}
|
|
|
|
WriteThread::Writer nonmem_w;
|
|
if (two_write_queues_) {
|
|
nonmem_write_thread_.EnterUnbatched(&nonmem_w, &mutex_);
|
|
}
|
|
for (const auto cfd : cfds) {
|
|
if (cfd->mem()->IsEmpty()) {
|
|
continue;
|
|
}
|
|
cfd->Ref();
|
|
status = SwitchMemtable(cfd, write_context);
|
|
cfd->Unref();
|
|
if (!status.ok()) {
|
|
break;
|
|
}
|
|
}
|
|
if (two_write_queues_) {
|
|
nonmem_write_thread_.ExitUnbatched(&nonmem_w);
|
|
}
|
|
|
|
if (status.ok()) {
|
|
if (immutable_db_options_.atomic_flush) {
|
|
AssignAtomicFlushSeq(cfds);
|
|
}
|
|
for (const auto cfd : cfds) {
|
|
cfd->imm()->FlushRequested();
|
|
}
|
|
FlushRequest flush_req;
|
|
GenerateFlushRequest(cfds, &flush_req);
|
|
SchedulePendingFlush(flush_req, FlushReason::kWriteBufferFull);
|
|
MaybeScheduleFlushOrCompaction();
|
|
}
|
|
return status;
|
|
}
|
|
|
|
uint64_t DBImpl::GetMaxTotalWalSize() const {
|
|
mutex_.AssertHeld();
|
|
return mutable_db_options_.max_total_wal_size == 0
|
|
? 4 * max_total_in_memory_state_
|
|
: mutable_db_options_.max_total_wal_size;
|
|
}
|
|
|
|
// REQUIRES: mutex_ is held
|
|
// REQUIRES: this thread is currently at the front of the writer queue
|
|
Status DBImpl::DelayWrite(uint64_t num_bytes,
|
|
const WriteOptions& write_options) {
|
|
uint64_t time_delayed = 0;
|
|
bool delayed = false;
|
|
{
|
|
StopWatch sw(env_, stats_, WRITE_STALL, &time_delayed);
|
|
uint64_t delay = write_controller_.GetDelay(env_, num_bytes);
|
|
if (delay > 0) {
|
|
if (write_options.no_slowdown) {
|
|
return Status::Incomplete("Write stall");
|
|
}
|
|
TEST_SYNC_POINT("DBImpl::DelayWrite:Sleep");
|
|
|
|
// Notify write_thread_ about the stall so it can setup a barrier and
|
|
// fail any pending writers with no_slowdown
|
|
write_thread_.BeginWriteStall();
|
|
TEST_SYNC_POINT("DBImpl::DelayWrite:BeginWriteStallDone");
|
|
mutex_.Unlock();
|
|
// We will delay the write until we have slept for delay ms or
|
|
// we don't need a delay anymore
|
|
const uint64_t kDelayInterval = 1000;
|
|
uint64_t stall_end = sw.start_time() + delay;
|
|
while (write_controller_.NeedsDelay()) {
|
|
if (env_->NowMicros() >= stall_end) {
|
|
// We already delayed this write `delay` microseconds
|
|
break;
|
|
}
|
|
|
|
delayed = true;
|
|
// Sleep for 0.001 seconds
|
|
env_->SleepForMicroseconds(kDelayInterval);
|
|
}
|
|
mutex_.Lock();
|
|
write_thread_.EndWriteStall();
|
|
}
|
|
|
|
// Don't wait if there's a background error, even if its a soft error. We
|
|
// might wait here indefinitely as the background compaction may never
|
|
// finish successfully, resulting in the stall condition lasting
|
|
// indefinitely
|
|
while (error_handler_.GetBGError().ok() && write_controller_.IsStopped()) {
|
|
if (write_options.no_slowdown) {
|
|
return Status::Incomplete("Write stall");
|
|
}
|
|
delayed = true;
|
|
|
|
// Notify write_thread_ about the stall so it can setup a barrier and
|
|
// fail any pending writers with no_slowdown
|
|
write_thread_.BeginWriteStall();
|
|
TEST_SYNC_POINT("DBImpl::DelayWrite:Wait");
|
|
bg_cv_.Wait();
|
|
write_thread_.EndWriteStall();
|
|
}
|
|
}
|
|
assert(!delayed || !write_options.no_slowdown);
|
|
if (delayed) {
|
|
default_cf_internal_stats_->AddDBStats(
|
|
InternalStats::kIntStatsWriteStallMicros, time_delayed);
|
|
RecordTick(stats_, STALL_MICROS, time_delayed);
|
|
}
|
|
|
|
// If DB is not in read-only mode and write_controller is not stopping
|
|
// writes, we can ignore any background errors and allow the write to
|
|
// proceed
|
|
Status s;
|
|
if (write_controller_.IsStopped()) {
|
|
// If writes are still stopped, it means we bailed due to a background
|
|
// error
|
|
s = Status::Incomplete(error_handler_.GetBGError().ToString());
|
|
}
|
|
if (error_handler_.IsDBStopped()) {
|
|
s = error_handler_.GetBGError();
|
|
}
|
|
return s;
|
|
}
|
|
|
|
Status DBImpl::ThrottleLowPriWritesIfNeeded(const WriteOptions& write_options,
|
|
WriteBatch* my_batch) {
|
|
assert(write_options.low_pri);
|
|
// This is called outside the DB mutex. Although it is safe to make the call,
|
|
// the consistency condition is not guaranteed to hold. It's OK to live with
|
|
// it in this case.
|
|
// If we need to speed compaction, it means the compaction is left behind
|
|
// and we start to limit low pri writes to a limit.
|
|
if (write_controller_.NeedSpeedupCompaction()) {
|
|
if (allow_2pc() && (my_batch->HasCommit() || my_batch->HasRollback())) {
|
|
// For 2PC, we only rate limit prepare, not commit.
|
|
return Status::OK();
|
|
}
|
|
if (write_options.no_slowdown) {
|
|
return Status::Incomplete();
|
|
} else {
|
|
assert(my_batch != nullptr);
|
|
// Rate limit those writes. The reason that we don't completely wait
|
|
// is that in case the write is heavy, low pri writes may never have
|
|
// a chance to run. Now we guarantee we are still slowly making
|
|
// progress.
|
|
PERF_TIMER_GUARD(write_delay_time);
|
|
write_controller_.low_pri_rate_limiter()->Request(
|
|
my_batch->GetDataSize(), Env::IO_HIGH, nullptr /* stats */,
|
|
RateLimiter::OpType::kWrite);
|
|
}
|
|
}
|
|
return Status::OK();
|
|
}
|
|
|
|
void DBImpl::MaybeFlushStatsCF(autovector<ColumnFamilyData*>* cfds) {
|
|
assert(cfds != nullptr);
|
|
if (!cfds->empty() && immutable_db_options_.persist_stats_to_disk) {
|
|
ColumnFamilyData* cfd_stats =
|
|
versions_->GetColumnFamilySet()->GetColumnFamily(
|
|
kPersistentStatsColumnFamilyName);
|
|
if (cfd_stats != nullptr && !cfd_stats->mem()->IsEmpty()) {
|
|
for (ColumnFamilyData* cfd : *cfds) {
|
|
if (cfd == cfd_stats) {
|
|
// stats CF already included in cfds
|
|
return;
|
|
}
|
|
}
|
|
// force flush stats CF when its log number is less than all other CF's
|
|
// log numbers
|
|
bool force_flush_stats_cf = true;
|
|
for (auto* loop_cfd : *versions_->GetColumnFamilySet()) {
|
|
if (loop_cfd == cfd_stats) {
|
|
continue;
|
|
}
|
|
if (loop_cfd->GetLogNumber() <= cfd_stats->GetLogNumber()) {
|
|
force_flush_stats_cf = false;
|
|
}
|
|
}
|
|
if (force_flush_stats_cf) {
|
|
cfds->push_back(cfd_stats);
|
|
ROCKS_LOG_INFO(immutable_db_options_.info_log,
|
|
"Force flushing stats CF with automated flush "
|
|
"to avoid holding old logs");
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
Status DBImpl::TrimMemtableHistory(WriteContext* context) {
|
|
autovector<ColumnFamilyData*> cfds;
|
|
ColumnFamilyData* tmp_cfd;
|
|
while ((tmp_cfd = trim_history_scheduler_.TakeNextColumnFamily()) !=
|
|
nullptr) {
|
|
cfds.push_back(tmp_cfd);
|
|
}
|
|
for (auto& cfd : cfds) {
|
|
autovector<MemTable*> to_delete;
|
|
cfd->imm()->TrimHistory(&to_delete, cfd->mem()->ApproximateMemoryUsage());
|
|
if (!to_delete.empty()) {
|
|
for (auto m : to_delete) {
|
|
delete m;
|
|
}
|
|
context->superversion_context.NewSuperVersion();
|
|
assert(context->superversion_context.new_superversion.get() != nullptr);
|
|
cfd->InstallSuperVersion(&context->superversion_context, &mutex_);
|
|
}
|
|
|
|
if (cfd->Unref()) {
|
|
delete cfd;
|
|
cfd = nullptr;
|
|
}
|
|
}
|
|
return Status::OK();
|
|
}
|
|
|
|
Status DBImpl::ScheduleFlushes(WriteContext* context) {
|
|
autovector<ColumnFamilyData*> cfds;
|
|
if (immutable_db_options_.atomic_flush) {
|
|
SelectColumnFamiliesForAtomicFlush(&cfds);
|
|
for (auto cfd : cfds) {
|
|
cfd->Ref();
|
|
}
|
|
flush_scheduler_.Clear();
|
|
} else {
|
|
ColumnFamilyData* tmp_cfd;
|
|
while ((tmp_cfd = flush_scheduler_.TakeNextColumnFamily()) != nullptr) {
|
|
cfds.push_back(tmp_cfd);
|
|
}
|
|
MaybeFlushStatsCF(&cfds);
|
|
}
|
|
Status status;
|
|
WriteThread::Writer nonmem_w;
|
|
if (two_write_queues_) {
|
|
nonmem_write_thread_.EnterUnbatched(&nonmem_w, &mutex_);
|
|
}
|
|
|
|
for (auto& cfd : cfds) {
|
|
if (!cfd->mem()->IsEmpty()) {
|
|
status = SwitchMemtable(cfd, context);
|
|
}
|
|
if (cfd->Unref()) {
|
|
delete cfd;
|
|
cfd = nullptr;
|
|
}
|
|
if (!status.ok()) {
|
|
break;
|
|
}
|
|
}
|
|
|
|
if (two_write_queues_) {
|
|
nonmem_write_thread_.ExitUnbatched(&nonmem_w);
|
|
}
|
|
|
|
if (status.ok()) {
|
|
if (immutable_db_options_.atomic_flush) {
|
|
AssignAtomicFlushSeq(cfds);
|
|
}
|
|
FlushRequest flush_req;
|
|
GenerateFlushRequest(cfds, &flush_req);
|
|
SchedulePendingFlush(flush_req, FlushReason::kWriteBufferFull);
|
|
MaybeScheduleFlushOrCompaction();
|
|
}
|
|
return status;
|
|
}
|
|
|
|
#ifndef ROCKSDB_LITE
|
|
void DBImpl::NotifyOnMemTableSealed(ColumnFamilyData* /*cfd*/,
|
|
const MemTableInfo& mem_table_info) {
|
|
if (immutable_db_options_.listeners.size() == 0U) {
|
|
return;
|
|
}
|
|
if (shutting_down_.load(std::memory_order_acquire)) {
|
|
return;
|
|
}
|
|
|
|
for (auto listener : immutable_db_options_.listeners) {
|
|
listener->OnMemTableSealed(mem_table_info);
|
|
}
|
|
}
|
|
#endif // ROCKSDB_LITE
|
|
|
|
// REQUIRES: mutex_ is held
|
|
// REQUIRES: this thread is currently at the front of the writer queue
|
|
// REQUIRES: this thread is currently at the front of the 2nd writer queue if
|
|
// two_write_queues_ is true (This is to simplify the reasoning.)
|
|
Status DBImpl::SwitchMemtable(ColumnFamilyData* cfd, WriteContext* context) {
|
|
mutex_.AssertHeld();
|
|
WriteThread::Writer nonmem_w;
|
|
std::unique_ptr<WritableFile> lfile;
|
|
log::Writer* new_log = nullptr;
|
|
MemTable* new_mem = nullptr;
|
|
|
|
// Recoverable state is persisted in WAL. After memtable switch, WAL might
|
|
// be deleted, so we write the state to memtable to be persisted as well.
|
|
Status s = WriteRecoverableState();
|
|
if (!s.ok()) {
|
|
return s;
|
|
}
|
|
|
|
// Attempt to switch to a new memtable and trigger flush of old.
|
|
// Do this without holding the dbmutex lock.
|
|
assert(versions_->prev_log_number() == 0);
|
|
if (two_write_queues_) {
|
|
log_write_mutex_.Lock();
|
|
}
|
|
bool creating_new_log = !log_empty_;
|
|
if (two_write_queues_) {
|
|
log_write_mutex_.Unlock();
|
|
}
|
|
uint64_t recycle_log_number = 0;
|
|
if (creating_new_log && immutable_db_options_.recycle_log_file_num &&
|
|
!log_recycle_files_.empty()) {
|
|
recycle_log_number = log_recycle_files_.front();
|
|
log_recycle_files_.pop_front();
|
|
}
|
|
uint64_t new_log_number =
|
|
creating_new_log ? versions_->NewFileNumber() : logfile_number_;
|
|
const MutableCFOptions mutable_cf_options = *cfd->GetLatestMutableCFOptions();
|
|
|
|
// Set memtable_info for memtable sealed callback
|
|
#ifndef ROCKSDB_LITE
|
|
MemTableInfo memtable_info;
|
|
memtable_info.cf_name = cfd->GetName();
|
|
memtable_info.first_seqno = cfd->mem()->GetFirstSequenceNumber();
|
|
memtable_info.earliest_seqno = cfd->mem()->GetEarliestSequenceNumber();
|
|
memtable_info.num_entries = cfd->mem()->num_entries();
|
|
memtable_info.num_deletes = cfd->mem()->num_deletes();
|
|
#endif // ROCKSDB_LITE
|
|
// Log this later after lock release. It may be outdated, e.g., if background
|
|
// flush happens before logging, but that should be ok.
|
|
int num_imm_unflushed = cfd->imm()->NumNotFlushed();
|
|
const auto preallocate_block_size =
|
|
GetWalPreallocateBlockSize(mutable_cf_options.write_buffer_size);
|
|
mutex_.Unlock();
|
|
if (creating_new_log) {
|
|
// TODO: Write buffer size passed in should be max of all CF's instead
|
|
// of mutable_cf_options.write_buffer_size.
|
|
s = CreateWAL(new_log_number, recycle_log_number, preallocate_block_size,
|
|
&new_log);
|
|
}
|
|
if (s.ok()) {
|
|
SequenceNumber seq = versions_->LastSequence();
|
|
new_mem = cfd->ConstructNewMemtable(mutable_cf_options, seq);
|
|
context->superversion_context.NewSuperVersion();
|
|
}
|
|
ROCKS_LOG_INFO(immutable_db_options_.info_log,
|
|
"[%s] New memtable created with log file: #%" PRIu64
|
|
". Immutable memtables: %d.\n",
|
|
cfd->GetName().c_str(), new_log_number, num_imm_unflushed);
|
|
mutex_.Lock();
|
|
if (s.ok() && creating_new_log) {
|
|
log_write_mutex_.Lock();
|
|
assert(new_log != nullptr);
|
|
if (!logs_.empty()) {
|
|
// Alway flush the buffer of the last log before switching to a new one
|
|
log::Writer* cur_log_writer = logs_.back().writer;
|
|
s = cur_log_writer->WriteBuffer();
|
|
if (!s.ok()) {
|
|
ROCKS_LOG_WARN(immutable_db_options_.info_log,
|
|
"[%s] Failed to switch from #%" PRIu64 " to #%" PRIu64
|
|
" WAL file\n",
|
|
cfd->GetName().c_str(), cur_log_writer->get_log_number(),
|
|
new_log_number);
|
|
}
|
|
}
|
|
if (s.ok()) {
|
|
logfile_number_ = new_log_number;
|
|
log_empty_ = true;
|
|
log_dir_synced_ = false;
|
|
logs_.emplace_back(logfile_number_, new_log);
|
|
alive_log_files_.push_back(LogFileNumberSize(logfile_number_));
|
|
}
|
|
log_write_mutex_.Unlock();
|
|
}
|
|
|
|
if (!s.ok()) {
|
|
// how do we fail if we're not creating new log?
|
|
assert(creating_new_log);
|
|
if (new_mem) {
|
|
delete new_mem;
|
|
}
|
|
if (new_log) {
|
|
delete new_log;
|
|
}
|
|
SuperVersion* new_superversion =
|
|
context->superversion_context.new_superversion.release();
|
|
if (new_superversion != nullptr) {
|
|
delete new_superversion;
|
|
}
|
|
// We may have lost data from the WritableFileBuffer in-memory buffer for
|
|
// the current log, so treat it as a fatal error and set bg_error
|
|
error_handler_.SetBGError(s, BackgroundErrorReason::kMemTable);
|
|
// Read back bg_error in order to get the right severity
|
|
s = error_handler_.GetBGError();
|
|
return s;
|
|
}
|
|
|
|
for (auto loop_cfd : *versions_->GetColumnFamilySet()) {
|
|
// all this is just optimization to delete logs that
|
|
// are no longer needed -- if CF is empty, that means it
|
|
// doesn't need that particular log to stay alive, so we just
|
|
// advance the log number. no need to persist this in the manifest
|
|
if (loop_cfd->mem()->GetFirstSequenceNumber() == 0 &&
|
|
loop_cfd->imm()->NumNotFlushed() == 0) {
|
|
if (creating_new_log) {
|
|
loop_cfd->SetLogNumber(logfile_number_);
|
|
}
|
|
loop_cfd->mem()->SetCreationSeq(versions_->LastSequence());
|
|
}
|
|
}
|
|
|
|
cfd->mem()->SetNextLogNumber(logfile_number_);
|
|
cfd->imm()->Add(cfd->mem(), &context->memtables_to_free_);
|
|
new_mem->Ref();
|
|
cfd->SetMemtable(new_mem);
|
|
InstallSuperVersionAndScheduleWork(cfd, &context->superversion_context,
|
|
mutable_cf_options);
|
|
#ifndef ROCKSDB_LITE
|
|
mutex_.Unlock();
|
|
// Notify client that memtable is sealed, now that we have successfully
|
|
// installed a new memtable
|
|
NotifyOnMemTableSealed(cfd, memtable_info);
|
|
mutex_.Lock();
|
|
#endif // ROCKSDB_LITE
|
|
return s;
|
|
}
|
|
|
|
size_t DBImpl::GetWalPreallocateBlockSize(uint64_t write_buffer_size) const {
|
|
mutex_.AssertHeld();
|
|
size_t bsize =
|
|
static_cast<size_t>(write_buffer_size / 10 + write_buffer_size);
|
|
// Some users might set very high write_buffer_size and rely on
|
|
// max_total_wal_size or other parameters to control the WAL size.
|
|
if (mutable_db_options_.max_total_wal_size > 0) {
|
|
bsize = std::min<size_t>(
|
|
bsize, static_cast<size_t>(mutable_db_options_.max_total_wal_size));
|
|
}
|
|
if (immutable_db_options_.db_write_buffer_size > 0) {
|
|
bsize = std::min<size_t>(bsize, immutable_db_options_.db_write_buffer_size);
|
|
}
|
|
if (immutable_db_options_.write_buffer_manager &&
|
|
immutable_db_options_.write_buffer_manager->enabled()) {
|
|
bsize = std::min<size_t>(
|
|
bsize, immutable_db_options_.write_buffer_manager->buffer_size());
|
|
}
|
|
|
|
return bsize;
|
|
}
|
|
|
|
// Default implementations of convenience methods that subclasses of DB
|
|
// can call if they wish
|
|
Status DB::Put(const WriteOptions& opt, ColumnFamilyHandle* column_family,
|
|
const Slice& key, const Slice& value) {
|
|
if (nullptr == opt.timestamp) {
|
|
// Pre-allocate size of write batch conservatively.
|
|
// 8 bytes are taken by header, 4 bytes for count, 1 byte for type,
|
|
// and we allocate 11 extra bytes for key length, as well as value length.
|
|
WriteBatch batch(key.size() + value.size() + 24);
|
|
Status s = batch.Put(column_family, key, value);
|
|
if (!s.ok()) {
|
|
return s;
|
|
}
|
|
return Write(opt, &batch);
|
|
}
|
|
const Slice* ts = opt.timestamp;
|
|
assert(nullptr != ts);
|
|
size_t ts_sz = ts->size();
|
|
WriteBatch batch(key.size() + ts_sz + value.size() + 24, /*max_bytes=*/0,
|
|
ts_sz);
|
|
Status s = batch.Put(column_family, key, value);
|
|
if (!s.ok()) {
|
|
return s;
|
|
}
|
|
s = batch.AssignTimestamp(*ts);
|
|
if (!s.ok()) {
|
|
return s;
|
|
}
|
|
return Write(opt, &batch);
|
|
}
|
|
|
|
Status DB::Delete(const WriteOptions& opt, ColumnFamilyHandle* column_family,
|
|
const Slice& key) {
|
|
WriteBatch batch;
|
|
batch.Delete(column_family, key);
|
|
return Write(opt, &batch);
|
|
}
|
|
|
|
Status DB::SingleDelete(const WriteOptions& opt,
|
|
ColumnFamilyHandle* column_family, const Slice& key) {
|
|
WriteBatch batch;
|
|
batch.SingleDelete(column_family, key);
|
|
return Write(opt, &batch);
|
|
}
|
|
|
|
Status DB::DeleteRange(const WriteOptions& opt,
|
|
ColumnFamilyHandle* column_family,
|
|
const Slice& begin_key, const Slice& end_key) {
|
|
WriteBatch batch;
|
|
batch.DeleteRange(column_family, begin_key, end_key);
|
|
return Write(opt, &batch);
|
|
}
|
|
|
|
Status DB::Merge(const WriteOptions& opt, ColumnFamilyHandle* column_family,
|
|
const Slice& key, const Slice& value) {
|
|
WriteBatch batch;
|
|
Status s = batch.Merge(column_family, key, value);
|
|
if (!s.ok()) {
|
|
return s;
|
|
}
|
|
return Write(opt, &batch);
|
|
}
|
|
} // namespace rocksdb
|