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rocksdb/cache/lru_secondary_cache.cc

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6.0 KiB

// 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).
#include "cache/lru_secondary_cache.h"
#include <memory>
#include "memory/memory_allocator.h"
#include "util/compression.h"
#include "util/string_util.h"
namespace ROCKSDB_NAMESPACE {
namespace {
void DeletionCallback(const Slice& /*key*/, void* obj) {
delete reinterpret_cast<CacheAllocationPtr*>(obj);
obj = nullptr;
}
} // namespace
LRUSecondaryCache::LRUSecondaryCache(
size_t capacity, int num_shard_bits, bool strict_capacity_limit,
double high_pri_pool_ratio,
std::shared_ptr<MemoryAllocator> memory_allocator, bool use_adaptive_mutex,
CacheMetadataChargePolicy metadata_charge_policy,
CompressionType compression_type, uint32_t compress_format_version)
: cache_options_(capacity, num_shard_bits, strict_capacity_limit,
high_pri_pool_ratio, memory_allocator, use_adaptive_mutex,
metadata_charge_policy, compression_type,
compress_format_version) {
cache_ = NewLRUCache(capacity, num_shard_bits, strict_capacity_limit,
high_pri_pool_ratio, memory_allocator,
use_adaptive_mutex, metadata_charge_policy);
}
LRUSecondaryCache::~LRUSecondaryCache() { cache_.reset(); }
std::unique_ptr<SecondaryCacheResultHandle> LRUSecondaryCache::Lookup(
const Slice& key, const Cache::CreateCallback& create_cb, bool /*wait*/) {
std::unique_ptr<SecondaryCacheResultHandle> handle;
Cache::Handle* lru_handle = cache_->Lookup(key);
if (lru_handle == nullptr) {
return handle;
}
CacheAllocationPtr* ptr =
reinterpret_cast<CacheAllocationPtr*>(cache_->Value(lru_handle));
void* value = nullptr;
size_t charge = 0;
Status s;
if (cache_options_.compression_type == kNoCompression) {
s = create_cb(ptr->get(), cache_->GetCharge(lru_handle), &value, &charge);
} else {
UncompressionContext uncompression_context(cache_options_.compression_type);
UncompressionInfo uncompression_info(uncompression_context,
UncompressionDict::GetEmptyDict(),
cache_options_.compression_type);
size_t uncompressed_size = 0;
CacheAllocationPtr uncompressed;
uncompressed = UncompressData(
uncompression_info, (char*)ptr->get(), cache_->GetCharge(lru_handle),
&uncompressed_size, cache_options_.compress_format_version,
cache_options_.memory_allocator.get());
if (!uncompressed) {
cache_->Release(lru_handle, true);
return handle;
}
s = create_cb(uncompressed.get(), uncompressed_size, &value, &charge);
}
if (!s.ok()) {
cache_->Release(lru_handle, true);
return handle;
}
handle.reset(new LRUSecondaryCacheResultHandle(value, charge));
cache_->Release(lru_handle);
return handle;
}
Status LRUSecondaryCache::Insert(const Slice& key, void* value,
const Cache::CacheItemHelper* helper) {
size_t size = (*helper->size_cb)(value);
CacheAllocationPtr ptr =
AllocateBlock(size, cache_options_.memory_allocator.get());
Status s = (*helper->saveto_cb)(value, 0, size, ptr.get());
if (!s.ok()) {
return s;
}
Slice val(ptr.get(), size);
std::string compressed_val;
if (cache_options_.compression_type != kNoCompression) {
CompressionOptions compression_opts;
CompressionContext compression_context(cache_options_.compression_type);
uint64_t sample_for_compression = 0;
CompressionInfo compression_info(
compression_opts, compression_context, CompressionDict::GetEmptyDict(),
cache_options_.compression_type, sample_for_compression);
bool success =
CompressData(val, compression_info,
cache_options_.compress_format_version, &compressed_val);
if (!success) {
return Status::Corruption("Error compressing value.");
}
val = Slice(compressed_val);
size = compressed_val.size();
ptr = AllocateBlock(size, cache_options_.memory_allocator.get());
memcpy(ptr.get(), compressed_val.data(), size);
}
CacheAllocationPtr* buf = new CacheAllocationPtr(std::move(ptr));
return cache_->Insert(key, buf, size, DeletionCallback);
}
void LRUSecondaryCache::Erase(const Slice& key) { cache_->Erase(key); }
std::string LRUSecondaryCache::GetPrintableOptions() const {
std::string ret;
ret.reserve(20000);
const int kBufferSize = 200;
char buffer[kBufferSize];
ret.append(cache_->GetPrintableOptions());
snprintf(buffer, kBufferSize, " compression_type : %s\n",
CompressionTypeToString(cache_options_.compression_type).c_str());
ret.append(buffer);
snprintf(buffer, kBufferSize, " compression_type : %d\n",
cache_options_.compress_format_version);
ret.append(buffer);
return ret;
}
std::shared_ptr<SecondaryCache> NewLRUSecondaryCache(
size_t capacity, int num_shard_bits, bool strict_capacity_limit,
double high_pri_pool_ratio,
std::shared_ptr<MemoryAllocator> memory_allocator, bool use_adaptive_mutex,
CacheMetadataChargePolicy metadata_charge_policy,
CompressionType compression_type, uint32_t compress_format_version) {
return std::make_shared<LRUSecondaryCache>(
capacity, num_shard_bits, strict_capacity_limit, high_pri_pool_ratio,
memory_allocator, use_adaptive_mutex, metadata_charge_policy,
compression_type, compress_format_version);
}
std::shared_ptr<SecondaryCache> NewLRUSecondaryCache(
const LRUSecondaryCacheOptions& opts) {
// The secondary_cache is disabled for this LRUCache instance.
assert(opts.secondary_cache == nullptr);
return NewLRUSecondaryCache(
opts.capacity, opts.num_shard_bits, opts.strict_capacity_limit,
opts.high_pri_pool_ratio, opts.memory_allocator, opts.use_adaptive_mutex,
opts.metadata_charge_policy, opts.compression_type,
opts.compress_format_version);
}
} // namespace ROCKSDB_NAMESPACE