rocksdb/db/memtable_allocator.cc
sdong 6797e6ffac Avoid updating memtable allocated bytes if write_buffer_size is not set
Summary: If options.write_buffer_size is not set, nor options.write_buffer_manager, no need to update the bytes allocated counter in MemTableAllocator, which is expensive in parallel memtable insert case. Remove it can improve parallel memtable insert throughput by 10% with write batch size 128.

Test Plan:
Run benchmarks
TEST_TMPDIR=/dev/shm/ ./db_bench --benchmarks=fillrandom -disable_auto_compactions -level0_slowdown_writes_trigger=9999 -level0_stop_writes_trigger=9999 -num=10000000 --writes=1000000 -max_background_flushes=16 -max_write_buffer_number=16 --threads=32 --batch_size=128   -allow_concurrent_memtable_write -enable_write_thread_adaptive_yield

The throughput grows 10% with the benchmark.

Reviewers: andrewkr, yiwu, IslamAbdelRahman, igor, ngbronson

Reviewed By: ngbronson

Subscribers: ngbronson, leveldb, andrewkr, dhruba

Differential Revision: https://reviews.facebook.net/D60465
2016-07-13 19:33:57 -07:00

60 lines
2.1 KiB
C++

// Copyright (c) 2011-present, Facebook, Inc. All rights reserved.
// This source code is licensed under the BSD-style license found in the
// LICENSE file in the root directory of this source tree. An additional grant
// of patent rights can be found in the PATENTS file in the same directory.
//
// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file. See the AUTHORS file for names of contributors.
#include "db/memtable_allocator.h"
#include <assert.h>
#include "rocksdb/write_buffer_manager.h"
#include "util/arena.h"
namespace rocksdb {
MemTableAllocator::MemTableAllocator(Allocator* allocator,
WriteBufferManager* write_buffer_manager)
: allocator_(allocator),
write_buffer_manager_(write_buffer_manager),
bytes_allocated_(0) {}
MemTableAllocator::~MemTableAllocator() { DoneAllocating(); }
char* MemTableAllocator::Allocate(size_t bytes) {
assert(write_buffer_manager_ != nullptr);
if (write_buffer_manager_->enabled()) {
bytes_allocated_.fetch_add(bytes, std::memory_order_relaxed);
write_buffer_manager_->ReserveMem(bytes);
}
return allocator_->Allocate(bytes);
}
char* MemTableAllocator::AllocateAligned(size_t bytes, size_t huge_page_size,
Logger* logger) {
assert(write_buffer_manager_ != nullptr);
if (write_buffer_manager_->enabled()) {
bytes_allocated_.fetch_add(bytes, std::memory_order_relaxed);
write_buffer_manager_->ReserveMem(bytes);
}
return allocator_->AllocateAligned(bytes, huge_page_size, logger);
}
void MemTableAllocator::DoneAllocating() {
if (write_buffer_manager_ != nullptr) {
if (write_buffer_manager_->enabled()) {
write_buffer_manager_->FreeMem(
bytes_allocated_.load(std::memory_order_relaxed));
} else {
assert(bytes_allocated_.load(std::memory_order_relaxed) == 0);
}
write_buffer_manager_ = nullptr;
}
}
size_t MemTableAllocator::BlockSize() const { return allocator_->BlockSize(); }
} // namespace rocksdb