2f41ecfe75
Summary: MyRocks currently sets `max_write_buffer_number_to_maintain` in order to maintain enough history for transaction conflict checking. The effectiveness of this approach depends on the size of memtables. When memtables are small, it may not keep enough history; when memtables are large, this may consume too much memory. We are proposing a new way to configure memtable list history: by limiting the memory usage of immutable memtables. The new option is `max_write_buffer_size_to_maintain` and it will take precedence over the old `max_write_buffer_number_to_maintain` if they are both set to non-zero values. The new option accounts for the total memory usage of flushed immutable memtables and mutable memtable. When the total usage exceeds the limit, RocksDB may start dropping immutable memtables (which is also called trimming history), starting from the oldest one. The semantics of the old option actually works both as an upper bound and lower bound. History trimming will start if number of immutable memtables exceeds the limit, but it will never go below (limit-1) due to history trimming. In order the mimic the behavior with the new option, history trimming will stop if dropping the next immutable memtable causes the total memory usage go below the size limit. For example, assuming the size limit is set to 64MB, and there are 3 immutable memtables with sizes of 20, 30, 30. Although the total memory usage is 80MB > 64MB, dropping the oldest memtable will reduce the memory usage to 60MB < 64MB, so in this case no memtable will be dropped. Pull Request resolved: https://github.com/facebook/rocksdb/pull/5022 Differential Revision: D14394062 Pulled By: miasantreble fbshipit-source-id: 60457a509c6af89d0993f988c9b5c2aa9e45f5c5
1818 lines
67 KiB
C++
1818 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_);
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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::NUMBER_KEYS_WRITTEN, 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::BYTES_WRITTEN, 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::WRITE_DONE_BY_SELF, 1, 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::WRITE_DONE_BY_OTHER, write_done_by_other,
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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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}
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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.
|
|
versions_->SetLastSequence(last_sequence);
|
|
}
|
|
MemTableInsertStatusCheck(w.status);
|
|
write_thread_.ExitAsBatchGroupLeader(write_group, status);
|
|
}
|
|
|
|
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::NUMBER_KEYS_WRITTEN, total_count);
|
|
RecordTick(stats_, NUMBER_KEYS_WRITTEN, total_count);
|
|
stats->AddDBStats(InternalStats::BYTES_WRITTEN, 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::WRITE_DONE_BY_SELF, 1);
|
|
RecordTick(stats_, WRITE_DONE_BY_SELF, 1);
|
|
if (wal_write_group.size > 1) {
|
|
stats->AddDBStats(InternalStats::WRITE_DONE_BY_OTHER,
|
|
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*/);
|
|
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::NUMBER_KEYS_WRITTEN, 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);
|
|
|
|
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::BYTES_WRITTEN, total_byte_size,
|
|
concurrent_update);
|
|
RecordTick(stats_, BYTES_WRITTEN, total_byte_size);
|
|
stats->AddDBStats(InternalStats::WRITE_DONE_BY_SELF, 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::WRITE_DONE_BY_OTHER, 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::WAL_FILE_SYNCED, 1);
|
|
RecordTick(stats_, WAL_FILE_SYNCED);
|
|
}
|
|
stats->AddDBStats(InternalStats::WAL_FILE_BYTES, log_size);
|
|
RecordTick(stats_, WAL_FILE_BYTES, log_size);
|
|
stats->AddDBStats(InternalStats::WRITE_WITH_WAL, 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::WAL_FILE_BYTES, log_size, concurrent);
|
|
RecordTick(stats_, WAL_FILE_BYTES, log_size);
|
|
stats->AddDBStats(InternalStats::WRITE_WITH_WAL, 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);
|
|
}
|
|
for (const auto cfd : cfds) {
|
|
cfd->Ref();
|
|
status = SwitchMemtable(cfd, write_context);
|
|
cfd->Unref();
|
|
if (!status.ok()) {
|
|
break;
|
|
}
|
|
}
|
|
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);
|
|
}
|
|
|
|
for (const auto cfd : cfds) {
|
|
if (cfd->mem()->IsEmpty()) {
|
|
continue;
|
|
}
|
|
cfd->Ref();
|
|
status = SwitchMemtable(cfd, write_context);
|
|
cfd->Unref();
|
|
if (!status.ok()) {
|
|
break;
|
|
}
|
|
}
|
|
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::WRITE_STALL_MICROS,
|
|
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());
|
|
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;
|
|
for (auto& cfd : cfds) {
|
|
if (!cfd->mem()->IsEmpty()) {
|
|
status = SwitchMemtable(cfd, context);
|
|
}
|
|
if (cfd->Unref()) {
|
|
delete cfd;
|
|
cfd = nullptr;
|
|
}
|
|
if (!status.ok()) {
|
|
break;
|
|
}
|
|
}
|
|
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
|
|
Status DBImpl::SwitchMemtable(ColumnFamilyData* cfd, WriteContext* context) {
|
|
mutex_.AssertHeld();
|
|
WriteThread::Writer nonmem_w;
|
|
if (two_write_queues_) {
|
|
// SwitchMemtable is a rare event. To simply the reasoning, we make sure
|
|
// that there is no concurrent thread writing to WAL.
|
|
nonmem_write_thread_.EnterUnbatched(&nonmem_w, &mutex_);
|
|
}
|
|
|
|
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;
|
|
}
|
|
|
|
// In case of pipelined write is enabled, wait for all pending memtable
|
|
// writers.
|
|
if (immutable_db_options_.enable_pipelined_write) {
|
|
// Memtable writers may call DB::Get in case max_successive_merges > 0,
|
|
// which may lock mutex. Unlocking mutex here to avoid deadlock.
|
|
mutex_.Unlock();
|
|
write_thread_.WaitForMemTableWriters();
|
|
mutex_.Lock();
|
|
}
|
|
|
|
// 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();
|
|
|
|
if (two_write_queues_) {
|
|
nonmem_write_thread_.ExitUnbatched(&nonmem_w);
|
|
}
|
|
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
|
|
if (two_write_queues_) {
|
|
nonmem_write_thread_.ExitUnbatched(&nonmem_w);
|
|
}
|
|
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
|