rocksdb/util/trace_replay.h

97 lines
2.3 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 <memory>
#include <unordered_map>
#include <utility>
#include "rocksdb/env.h"
#include "rocksdb/trace_reader_writer.h"
namespace rocksdb {
class ColumnFamilyHandle;
class ColumnFamilyData;
class DB;
class DBImpl;
class Slice;
class WriteBatch;
const std::string kTraceMagic = "feedcafedeadbeef";
const unsigned int kTraceTimestampSize = 8;
const unsigned int kTraceTypeSize = 1;
const unsigned int kTracePayloadLengthSize = 4;
const unsigned int kTraceMetadataSize =
kTraceTimestampSize + kTraceTypeSize + kTracePayloadLengthSize;
enum TraceType : char {
kTraceBegin = 1,
kTraceEnd = 2,
kTraceWrite = 3,
kTraceGet = 4,
kTraceIteratorSeek = 5,
kTraceIteratorSeekForPrev = 6,
kTraceMax,
};
// TODO: This should also be made part of public interface to help users build
// custom TracerReaders and TraceWriters.
struct Trace {
uint64_t ts;
TraceType type;
std::string payload;
void reset() {
ts = 0;
type = kTraceMax;
payload.clear();
}
};
// Trace RocksDB operations using a TraceWriter.
class Tracer {
public:
Tracer(Env* env, std::unique_ptr<TraceWriter>&& trace_writer);
~Tracer();
Status Write(WriteBatch* write_batch);
Status Get(ColumnFamilyHandle* cfname, const Slice& key);
Status IteratorSeek(const uint32_t& cf_id, const Slice& key);
Status IteratorSeekForPrev(const uint32_t& cf_id, const Slice& key);
Status Close();
private:
Status WriteHeader();
Status WriteFooter();
Status WriteTrace(const Trace& trace);
Env* env_;
unique_ptr<TraceWriter> trace_writer_;
};
// Replay RocksDB operations from a trace.
class Replayer {
public:
Replayer(DB* db, const std::vector<ColumnFamilyHandle*>& handles,
std::unique_ptr<TraceReader>&& reader);
~Replayer();
Status Replay();
private:
Status ReadHeader(Trace* header);
Status ReadFooter(Trace* footer);
Status ReadTrace(Trace* trace);
DBImpl* db_;
std::unique_ptr<TraceReader> trace_reader_;
std::unordered_map<uint32_t, ColumnFamilyHandle*> cf_map_;
};
} // namespace rocksdb