rocksdb/db/blob/blob_file_reader.h
Gang Liao 056e08d6c4 Enable blob caching for MultiGetBlob in RocksDB (#10272)
Summary:
- [x] Enabled blob caching for MultiGetBlob in RocksDB
- [x] Refactored MultiGetBlob logic and interface in RocksDB
- [x] Cleaned up Version::MultiGetBlob() and moved 'blob'-related code snippets into BlobSource
- [x] Add End-to-end test cases in db_blob_basic_test and also add unit tests in blob_source_test

This task is a part of https://github.com/facebook/rocksdb/issues/10156

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10272

Reviewed By: ltamasi

Differential Revision: D37558112

Pulled By: gangliao

fbshipit-source-id: a73a6a94ffdee0024d5b2a39e6d1c1a7d38664db
2022-06-30 13:24:35 -07:00

106 lines
4 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).
#pragma once
#include <cinttypes>
#include <memory>
#include "db/blob/blob_read_request.h"
#include "file/random_access_file_reader.h"
#include "rocksdb/compression_type.h"
#include "rocksdb/rocksdb_namespace.h"
#include "util/autovector.h"
namespace ROCKSDB_NAMESPACE {
class Status;
struct ImmutableOptions;
struct FileOptions;
class HistogramImpl;
struct ReadOptions;
class Slice;
class FilePrefetchBuffer;
class PinnableSlice;
class Statistics;
class BlobFileReader {
public:
static Status Create(const ImmutableOptions& immutable_options,
const FileOptions& file_options,
uint32_t column_family_id,
HistogramImpl* blob_file_read_hist,
uint64_t blob_file_number,
const std::shared_ptr<IOTracer>& io_tracer,
std::unique_ptr<BlobFileReader>* reader);
BlobFileReader(const BlobFileReader&) = delete;
BlobFileReader& operator=(const BlobFileReader&) = delete;
~BlobFileReader();
Status GetBlob(const ReadOptions& read_options, const Slice& user_key,
uint64_t offset, uint64_t value_size,
CompressionType compression_type,
FilePrefetchBuffer* prefetch_buffer, PinnableSlice* value,
uint64_t* bytes_read) const;
// offsets must be sorted in ascending order by caller.
void MultiGetBlob(const ReadOptions& read_options,
autovector<BlobReadRequest*>& blob_reqs,
uint64_t* bytes_read) const;
CompressionType GetCompressionType() const { return compression_type_; }
uint64_t GetFileSize() const { return file_size_; }
private:
BlobFileReader(std::unique_ptr<RandomAccessFileReader>&& file_reader,
uint64_t file_size, CompressionType compression_type,
SystemClock* clock, Statistics* statistics);
static Status OpenFile(const ImmutableOptions& immutable_options,
const FileOptions& file_opts,
HistogramImpl* blob_file_read_hist,
uint64_t blob_file_number,
const std::shared_ptr<IOTracer>& io_tracer,
uint64_t* file_size,
std::unique_ptr<RandomAccessFileReader>* file_reader);
static Status ReadHeader(const RandomAccessFileReader* file_reader,
uint32_t column_family_id, Statistics* statistics,
CompressionType* compression_type);
static Status ReadFooter(const RandomAccessFileReader* file_reader,
uint64_t file_size, Statistics* statistics);
using Buffer = std::unique_ptr<char[]>;
static Status ReadFromFile(const RandomAccessFileReader* file_reader,
uint64_t read_offset, size_t read_size,
Statistics* statistics, Slice* slice, Buffer* buf,
AlignedBuf* aligned_buf,
Env::IOPriority rate_limiter_priority);
static Status VerifyBlob(const Slice& record_slice, const Slice& user_key,
uint64_t value_size);
static Status UncompressBlobIfNeeded(const Slice& value_slice,
CompressionType compression_type,
SystemClock* clock,
Statistics* statistics,
PinnableSlice* value);
static void SaveValue(const Slice& src, PinnableSlice* dst);
std::unique_ptr<RandomAccessFileReader> file_reader_;
uint64_t file_size_;
CompressionType compression_type_;
SystemClock* clock_;
Statistics* statistics_;
};
} // namespace ROCKSDB_NAMESPACE