mirror of https://github.com/facebook/rocksdb.git
46 lines
1.6 KiB
C++
46 lines
1.6 KiB
C++
// Copyright (c) 2011-present, Facebook, Inc. All rights reserved.
|
|
// This source code is licensed under both the GPLv2 (found in the
|
|
// COPYING file in the root directory) and Apache 2.0 License
|
|
// (found in the LICENSE.Apache file in the root directory).
|
|
//
|
|
// 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 "memory/concurrent_arena.h"
|
|
|
|
#include <thread>
|
|
|
|
#include "port/port.h"
|
|
#include "util/random.h"
|
|
|
|
namespace ROCKSDB_NAMESPACE {
|
|
|
|
thread_local size_t ConcurrentArena::tls_cpuid = 0;
|
|
|
|
namespace {
|
|
// If the shard block size is too large, in the worst case, every core
|
|
// allocates a block without populate it. If the shared block size is
|
|
// 1MB, 64 cores will quickly allocate 64MB, and may quickly trigger a
|
|
// flush. Cap the size instead.
|
|
const size_t kMaxShardBlockSize = size_t{128 * 1024};
|
|
} // namespace
|
|
|
|
ConcurrentArena::ConcurrentArena(size_t block_size, AllocTracker* tracker,
|
|
size_t huge_page_size)
|
|
: shard_block_size_(std::min(kMaxShardBlockSize, block_size / 8)),
|
|
shards_(),
|
|
arena_(block_size, tracker, huge_page_size) {
|
|
Fixup();
|
|
}
|
|
|
|
ConcurrentArena::Shard* ConcurrentArena::Repick() {
|
|
auto shard_and_index = shards_.AccessElementAndIndex();
|
|
// 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();
|
|
return shard_and_index.first;
|
|
}
|
|
|
|
} // namespace ROCKSDB_NAMESPACE
|