Files
doris/be/src/runtime/mem_pool.cpp
ZHAO Chun 11eafe524f Add ChunkAllocator to accelerate chunk allocation (#1792)
I add ChunkAllocator in this CL to put unused memory chunk to a chunk
pool other than return it to system allocator. Now we only change
MemPool's chunk allocation and free to this.

And two configuration are introduduced too. 'chunk_reserved_bytes_limit'
is the limit of how many bytes this chunk pool can reserve in total and
its default value is 2147483648(2GB). 'use_mmap_allocate_chunk': if
chunk is allocated via mmap and default value is false.

And in my test case with default configuration a simple like
"select * from table limit 10", this can improve throughput from 280 QPS
to to 650 QPS. And when I config 'chunk_reserved_bytes_limit' to 0,
which means this is disabled, the throughput is the same with origin's.
2019-09-13 08:27:24 +08:00

264 lines
9.5 KiB
C++

// Licensed to the Apache Software Foundation (ASF) under one
// or more contributor license agreements. See the NOTICE file
// distributed with this work for additional information
// regarding copyright ownership. The ASF licenses this file
// to you under the Apache License, Version 2.0 (the
// "License"); you may not use this file except in compliance
// with the License. You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing,
// software distributed under the License is distributed on an
// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
// KIND, either express or implied. See the License for the
// specific language governing permissions and limitations
// under the License.
#include "runtime/memory/chunk_allocator.h"
#include "runtime/mem_pool.h"
#include "runtime/mem_tracker.h"
#include "util/bit_util.h"
#include "util/doris_metrics.h"
#include <algorithm>
#include <stdio.h>
#include <sstream>
#include "common/names.h"
namespace doris {
#define MEM_POOL_POISON (0x66aa77bb)
const int MemPool::INITIAL_CHUNK_SIZE;
const int MemPool::MAX_CHUNK_SIZE;
const char* MemPool::LLVM_CLASS_NAME = "class.doris::MemPool";
const int MemPool::DEFAULT_ALIGNMENT;
uint32_t MemPool::k_zero_length_region_ alignas(std::max_align_t) = MEM_POOL_POISON;
MemPool::ChunkInfo::ChunkInfo(const Chunk& chunk_)
: chunk(chunk_),
allocated_bytes(0) {
DorisMetrics::memory_pool_bytes_total.increment(chunk.size);
}
MemPool::~MemPool() {
int64_t total_bytes_released = 0;
for (auto& chunk : chunks_) {
total_bytes_released += chunk.chunk.size;
ChunkAllocator::instance()->free(chunk.chunk);
}
mem_tracker_->release(total_bytes_released);
DorisMetrics::memory_pool_bytes_total.increment(-total_bytes_released);
}
void MemPool::clear() {
current_chunk_idx_ = -1;
for (auto& chunk: chunks_) {
chunk.allocated_bytes = 0;
ASAN_POISON_MEMORY_REGION(chunk.chunk.data, chunk.chunk.size);
}
total_allocated_bytes_ = 0;
DCHECK(check_integrity(false));
}
void MemPool::free_all() {
int64_t total_bytes_released = 0;
for (auto& chunk: chunks_) {
total_bytes_released += chunk.chunk.size;
ChunkAllocator::instance()->free(chunk.chunk);
}
chunks_.clear();
next_chunk_size_ = INITIAL_CHUNK_SIZE;
current_chunk_idx_ = -1;
total_allocated_bytes_ = 0;
total_reserved_bytes_ = 0;
mem_tracker_->release(total_bytes_released);
DorisMetrics::memory_pool_bytes_total.increment(-total_bytes_released);
}
bool MemPool::find_chunk(size_t min_size, bool check_limits) {
// Try to allocate from a free chunk. We may have free chunks after the current chunk
// if Clear() was called. The current chunk may be free if ReturnPartialAllocation()
// was called. The first free chunk (if there is one) can therefore be either the
// current chunk or the chunk immediately after the current chunk.
int first_free_idx;
if (current_chunk_idx_ == -1) {
first_free_idx = 0;
} else {
DCHECK_GE(current_chunk_idx_, 0);
first_free_idx = current_chunk_idx_ +
(chunks_[current_chunk_idx_].allocated_bytes > 0);
}
for (int idx = current_chunk_idx_ + 1; idx < chunks_.size(); ++idx) {
// All chunks after 'current_chunk_idx_' should be free.
DCHECK_EQ(chunks_[idx].allocated_bytes, 0);
if (chunks_[idx].chunk.size >= min_size) {
// This chunk is big enough. Move it before the other free chunks.
if (idx != first_free_idx) std::swap(chunks_[idx], chunks_[first_free_idx]);
current_chunk_idx_ = first_free_idx;
DCHECK(check_integrity(true));
return true;
}
}
// Didn't find a big enough free chunk - need to allocate new chunk.
size_t chunk_size = 0;
DCHECK_LE(next_chunk_size_, MAX_CHUNK_SIZE);
if (config::disable_mem_pools) {
// Disable pooling by sizing the chunk to fit only this allocation.
// Make sure the alignment guarantees are respected.
chunk_size = std::max<size_t>(min_size, alignof(max_align_t));
} else {
DCHECK_GE(next_chunk_size_, INITIAL_CHUNK_SIZE);
chunk_size = max<size_t>(min_size, next_chunk_size_);
}
chunk_size = BitUtil::RoundUpToPowerOfTwo(chunk_size);
if (check_limits) {
if (!mem_tracker_->try_consume(chunk_size)) return false;
} else {
mem_tracker_->consume(chunk_size);
}
// Allocate a new chunk. Return early if allocate fails.
Chunk chunk;
if (!ChunkAllocator::instance()->allocate(chunk_size, &chunk)) {
mem_tracker_->release(chunk_size);
return false;
}
ASAN_POISON_MEMORY_REGION(chunk.data, chunk_size);
// Put it before the first free chunk. If no free chunks, it goes at the end.
if (first_free_idx == static_cast<int>(chunks_.size())) {
chunks_.emplace_back(chunk);
} else {
chunks_.insert(chunks_.begin() + first_free_idx, ChunkInfo(chunk));
}
current_chunk_idx_ = first_free_idx;
total_reserved_bytes_ += chunk_size;
// Don't increment the chunk size until the allocation succeeds: if an attempted
// large allocation fails we don't want to increase the chunk size further.
next_chunk_size_ = static_cast<int>(min<int64_t>(chunk_size * 2, MAX_CHUNK_SIZE));
DCHECK(check_integrity(true));
return true;
}
void MemPool::acquire_data(MemPool* src, bool keep_current) {
DCHECK(src->check_integrity(false));
int num_acquired_chunks;
if (keep_current) {
num_acquired_chunks = src->current_chunk_idx_;
} else if (src->get_free_offset() == 0) {
// nothing in the last chunk
num_acquired_chunks = src->current_chunk_idx_;
} else {
num_acquired_chunks = src->current_chunk_idx_ + 1;
}
if (num_acquired_chunks <= 0) {
if (!keep_current) src->free_all();
return;
}
auto end_chunk = src->chunks_.begin() + num_acquired_chunks;
int64_t total_transfered_bytes = 0;
for (auto i = src->chunks_.begin(); i != end_chunk; ++i) {
total_transfered_bytes += i->chunk.size;
}
src->total_reserved_bytes_ -= total_transfered_bytes;
total_reserved_bytes_ += total_transfered_bytes;
// Skip unnecessary atomic ops if the mem_trackers are the same.
if (src->mem_tracker_ != mem_tracker_) {
src->mem_tracker_->release(total_transfered_bytes);
mem_tracker_->consume(total_transfered_bytes);
}
// insert new chunks after current_chunk_idx_
auto insert_chunk = chunks_.begin() + current_chunk_idx_ + 1;
chunks_.insert(insert_chunk, src->chunks_.begin(), end_chunk);
src->chunks_.erase(src->chunks_.begin(), end_chunk);
current_chunk_idx_ += num_acquired_chunks;
if (keep_current) {
src->current_chunk_idx_ = 0;
DCHECK(src->chunks_.size() == 1 || src->chunks_[1].allocated_bytes == 0);
total_allocated_bytes_ += src->total_allocated_bytes_ - src->get_free_offset();
src->total_allocated_bytes_ = src->get_free_offset();
} else {
src->current_chunk_idx_ = -1;
total_allocated_bytes_ += src->total_allocated_bytes_;
src->total_allocated_bytes_ = 0;
}
peak_allocated_bytes_ = std::max(total_allocated_bytes_, peak_allocated_bytes_);
if (!keep_current) src->free_all();
DCHECK(src->check_integrity(false));
DCHECK(check_integrity(false));
}
void MemPool::exchange_data(MemPool* other) {
int64_t delta_size = other->total_reserved_bytes_ - total_reserved_bytes_;
std::swap(current_chunk_idx_, other->current_chunk_idx_);
std::swap(next_chunk_size_, other->next_chunk_size_);
std::swap(total_allocated_bytes_, other->total_allocated_bytes_);
std::swap(total_reserved_bytes_, other->total_reserved_bytes_);
std::swap(peak_allocated_bytes_, other->peak_allocated_bytes_);
std::swap(chunks_, other->chunks_);
// update MemTracker
mem_tracker_->consume(delta_size);
other->mem_tracker_->release(delta_size);
}
string MemPool::debug_string() {
stringstream out;
char str[16];
out << "MemPool(#chunks=" << chunks_.size() << " [";
for (int i = 0; i < chunks_.size(); ++i) {
sprintf(str, "0x%lx=", reinterpret_cast<size_t>(chunks_[i].chunk.data));
out << (i > 0 ? " " : "")
<< str
<< chunks_[i].chunk.size
<< "/" << chunks_[i].allocated_bytes;
}
out << "] current_chunk=" << current_chunk_idx_
<< " total_sizes=" << total_reserved_bytes_
<< " total_alloc=" << total_allocated_bytes_
<< ")";
return out.str();
}
bool MemPool::check_integrity(bool check_current_chunk_empty) {
DCHECK_LT(current_chunk_idx_, static_cast<int>(chunks_.size()));
// Without pooling, there are way too many chunks and this takes too long.
if (config::disable_mem_pools) return true;
// check that current_chunk_idx_ points to the last chunk with allocated data
int64_t total_allocated = 0;
for (int i = 0; i < chunks_.size(); ++i) {
DCHECK_GT(chunks_[i].chunk.size, 0);
if (i < current_chunk_idx_) {
DCHECK_GT(chunks_[i].allocated_bytes, 0);
} else if (i == current_chunk_idx_) {
DCHECK_GE(chunks_[i].allocated_bytes, 0);
if (check_current_chunk_empty) DCHECK_EQ(chunks_[i].allocated_bytes, 0);
} else {
DCHECK_EQ(chunks_[i].allocated_bytes, 0);
}
total_allocated += chunks_[i].allocated_bytes;
}
DCHECK_EQ(total_allocated, total_allocated_bytes_);
return true;
}
}