rocksdb/util/concurrent_arena.cc
Siying Dong 95b0e89b5d Improve write buffer manager (and allow the size to be tracked in block cache)
Summary:
Improve write buffer manager in several ways:
1. Size is tracked when arena block is allocated, rather than every allocation, so that it can better track actual memory usage and the tracking overhead is slightly lower.
2. We start to trigger memtable flush when 7/8 of the memory cap hits, instead of 100%, and make 100% much harder to hit.
3. Allow a cache object to be passed into buffer manager and the size allocated by memtable can be costed there. This can help users have one single memory cap across block cache and memtable.
Closes https://github.com/facebook/rocksdb/pull/2350

Differential Revision: D5110648

Pulled By: siying

fbshipit-source-id: b4238113094bf22574001e446b5d88523ba00017
2017-06-02 14:26:56 -07:00

42 lines
1.4 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.
// This source code is also licensed under the GPLv2 license found in the
// COPYING file in the root directory of this source tree.
//
// 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 "util/concurrent_arena.h"
#include <thread>
#include "port/port.h"
#include "util/random.h"
namespace rocksdb {
#ifdef ROCKSDB_SUPPORT_THREAD_LOCAL
__thread size_t ConcurrentArena::tls_cpuid = 0;
#endif
ConcurrentArena::ConcurrentArena(size_t block_size, AllocTracker* tracker,
size_t huge_page_size)
: shard_block_size_(block_size / 8),
shards_(),
arena_(block_size, tracker, huge_page_size) {
Fixup();
}
ConcurrentArena::Shard* ConcurrentArena::Repick() {
auto shard_and_index = shards_.AccessElementAndIndex();
#ifdef ROCKSDB_SUPPORT_THREAD_LOCAL
// even if we are cpu 0, use a non-zero tls_cpuid so we can tell we
// have repicked
tls_cpuid = shard_and_index.second | shards_.Size();
#endif
return shard_and_index.first;
}
} // namespace rocksdb