rocksdb/table/sst_file_writer_collectors.h
Islam AbdelRahman b88f8e87c5 Support SST files with Global sequence numbers [reland]
Summary:
reland https://reviews.facebook.net/D62523

- Update SstFileWriter to include a property for a global sequence number in the SST file `rocksdb.external_sst_file.global_seqno`
- Update TableProperties to be aware of the offset of each property in the file
- Update BlockBasedTableReader and Block to be able to honor the sequence number in `rocksdb.external_sst_file.global_seqno` property and use it to overwrite all sequence number in the file

Something worth mentioning is that we don't update the seqno in the index block since and when doing a binary search, the reason for that is that it's guaranteed that SST files with global seqno will have only one user_key and each key will have seqno=0 encoded in it, This mean that this key is greater than any other key with seqno> 0. That mean that we can actually keep the current logic for these blocks

Test Plan: unit tests

Reviewers: sdong, yhchiang

Subscribers: andrewkr, dhruba

Differential Revision: https://reviews.facebook.net/D65211
2016-10-18 16:59:37 -07:00

85 lines
2.8 KiB
C++

// Copyright (c) 2011-present, Facebook, Inc. All rights reserved.
// This source code is licensed under the BSD-style license found in the
// LICENSE file in the root directory of this source tree. An additional grant
// of patent rights can be found in the PATENTS file in the same directory.
#pragma once
#include <string>
#include "rocksdb/types.h"
#include "util/string_util.h"
namespace rocksdb {
// Table Properties that are specific to tables created by SstFileWriter.
struct ExternalSstFilePropertyNames {
// value of this property is a fixed uint32 number.
static const std::string kVersion;
// value of this property is a fixed uint64 number.
static const std::string kGlobalSeqno;
};
// PropertiesCollector used to add properties specific to tables
// generated by SstFileWriter
class SstFileWriterPropertiesCollector : public IntTblPropCollector {
public:
explicit SstFileWriterPropertiesCollector(int32_t version,
SequenceNumber global_seqno)
: version_(version), global_seqno_(global_seqno) {}
virtual Status InternalAdd(const Slice& key, const Slice& value,
uint64_t file_size) override {
// Intentionally left blank. Have no interest in collecting stats for
// individual key/value pairs.
return Status::OK();
}
virtual Status Finish(UserCollectedProperties* properties) override {
// File version
std::string version_val;
PutFixed32(&version_val, static_cast<uint32_t>(version_));
properties->insert({ExternalSstFilePropertyNames::kVersion, version_val});
// Global Sequence number
std::string seqno_val;
PutFixed64(&seqno_val, static_cast<uint64_t>(global_seqno_));
properties->insert({ExternalSstFilePropertyNames::kGlobalSeqno, seqno_val});
return Status::OK();
}
virtual const char* Name() const override {
return "SstFileWriterPropertiesCollector";
}
virtual UserCollectedProperties GetReadableProperties() const override {
return {{ExternalSstFilePropertyNames::kVersion, ToString(version_)}};
}
private:
int32_t version_;
SequenceNumber global_seqno_;
};
class SstFileWriterPropertiesCollectorFactory
: public IntTblPropCollectorFactory {
public:
explicit SstFileWriterPropertiesCollectorFactory(int32_t version,
SequenceNumber global_seqno)
: version_(version), global_seqno_(global_seqno) {}
virtual IntTblPropCollector* CreateIntTblPropCollector(
uint32_t column_family_id) override {
return new SstFileWriterPropertiesCollector(version_, global_seqno_);
}
virtual const char* Name() const override {
return "SstFileWriterPropertiesCollector";
}
private:
int32_t version_;
SequenceNumber global_seqno_;
};
} // namespace rocksdb