rocksdb/db/external_sst_file_ingestion_job.h
Giuseppe Ottaviano 4bfd415e34 Fix sequence number bump logic in multi-CF SST ingestion (#9005)
Summary:
The code in `IngestExternalFiles()` that bumps the DB's sequence number
depending on what seqnos were assigned to the files has 3 bugs:

1) There is an assertion that the sequence number is increased in all the
affected column families, but this is unnecessary, it is fine if some files can
stick to a lower sequence number. It is very easy to hit the assertion: it is
sufficient to insert 2 files in 2 CFs, one which overlaps the CF and one that
doesn't (for example the CF is empty). The line added in the
`IngestFilesIntoMultipleColumnFamilies_Success` test makes the assertion fail.

2) SetLastSequence() is called with the sum of all the bumps across CFs, but we
should take the maximum instead, as all CFs start with the current seqno and bump
it independently.

3) The code above is accidentally under a `#ifndef NDEBUG`, so it doesn't run in
optimized builds, so some files may be assigned seqnos from the future.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9005

Test Plan:
Added line in `IngestFilesIntoMultipleColumnFamilies_Success` that
triggers the assertion, verified that the test (and all the others) pass after
the fix.

Reviewed By: ajkr

Differential Revision: D31597892

Pulled By: ot

fbshipit-source-id: c2d3237f90290df1178736ace8653a9623f5a770
2021-10-12 20:39:52 -07:00

199 lines
7.4 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 <string>
#include <unordered_set>
#include <vector>
#include "db/column_family.h"
#include "db/internal_stats.h"
#include "db/snapshot_impl.h"
#include "env/file_system_tracer.h"
#include "logging/event_logger.h"
#include "options/db_options.h"
#include "rocksdb/db.h"
#include "rocksdb/file_system.h"
#include "rocksdb/sst_file_writer.h"
#include "util/autovector.h"
namespace ROCKSDB_NAMESPACE {
class Directories;
class SystemClock;
struct IngestedFileInfo {
// External file path
std::string external_file_path;
// Smallest internal key in external file
InternalKey smallest_internal_key;
// Largest internal key in external file
InternalKey largest_internal_key;
// Sequence number for keys in external file
SequenceNumber original_seqno;
// Offset of the global sequence number field in the file, will
// be zero if version is 1 (global seqno is not supported)
size_t global_seqno_offset;
// External file size
uint64_t file_size;
// total number of keys in external file
uint64_t num_entries;
// total number of range deletions in external file
uint64_t num_range_deletions;
// Id of column family this file shoule be ingested into
uint32_t cf_id;
// TableProperties read from external file
TableProperties table_properties;
// Version of external file
int version;
// FileDescriptor for the file inside the DB
FileDescriptor fd;
// file path that we picked for file inside the DB
std::string internal_file_path;
// Global sequence number that we picked for the file inside the DB
SequenceNumber assigned_seqno = 0;
// Level inside the DB we picked for the external file.
int picked_level = 0;
// Whether to copy or link the external sst file. copy_file will be set to
// false if ingestion_options.move_files is true and underlying FS
// supports link operation. Need to provide a default value to make the
// undefined-behavior sanity check of llvm happy. Since
// ingestion_options.move_files is false by default, thus copy_file is true
// by default.
bool copy_file = true;
// The checksum of ingested file
std::string file_checksum;
// The name of checksum function that generate the checksum
std::string file_checksum_func_name;
// The temperature of the file to be ingested
Temperature file_temperature = Temperature::kUnknown;
};
class ExternalSstFileIngestionJob {
public:
ExternalSstFileIngestionJob(
VersionSet* versions, ColumnFamilyData* cfd,
const ImmutableDBOptions& db_options, const EnvOptions& env_options,
SnapshotList* db_snapshots,
const IngestExternalFileOptions& ingestion_options,
Directories* directories, EventLogger* event_logger,
const std::shared_ptr<IOTracer>& io_tracer)
: clock_(db_options.clock),
fs_(db_options.fs, io_tracer),
versions_(versions),
cfd_(cfd),
db_options_(db_options),
env_options_(env_options),
db_snapshots_(db_snapshots),
ingestion_options_(ingestion_options),
directories_(directories),
event_logger_(event_logger),
job_start_time_(clock_->NowMicros()),
consumed_seqno_count_(0),
io_tracer_(io_tracer) {
assert(directories != nullptr);
}
// Prepare the job by copying external files into the DB.
Status Prepare(const std::vector<std::string>& external_files_paths,
const std::vector<std::string>& files_checksums,
const std::vector<std::string>& files_checksum_func_names,
const Temperature& file_temperature, uint64_t next_file_number,
SuperVersion* sv);
// Check if we need to flush the memtable before running the ingestion job
// This will be true if the files we are ingesting are overlapping with any
// key range in the memtable.
//
// @param super_version A referenced SuperVersion that will be held for the
// duration of this function.
//
// Thread-safe
Status NeedsFlush(bool* flush_needed, SuperVersion* super_version);
// Will execute the ingestion job and prepare edit() to be applied.
// REQUIRES: Mutex held
Status Run();
// Update column family stats.
// REQUIRES: Mutex held
void UpdateStats();
// Cleanup after successful/failed job
void Cleanup(const Status& status);
VersionEdit* edit() { return &edit_; }
const autovector<IngestedFileInfo>& files_to_ingest() const {
return files_to_ingest_;
}
// How many sequence numbers did we consume as part of the ingest job?
int ConsumedSequenceNumbersCount() const { return consumed_seqno_count_; }
private:
// Open the external file and populate `file_to_ingest` with all the
// external information we need to ingest this file.
Status GetIngestedFileInfo(const std::string& external_file,
IngestedFileInfo* file_to_ingest,
SuperVersion* sv);
// Assign `file_to_ingest` the appropriate sequence number and the lowest
// possible level that it can be ingested to according to compaction_style.
// REQUIRES: Mutex held
Status AssignLevelAndSeqnoForIngestedFile(SuperVersion* sv,
bool force_global_seqno,
CompactionStyle compaction_style,
SequenceNumber last_seqno,
IngestedFileInfo* file_to_ingest,
SequenceNumber* assigned_seqno);
// File that we want to ingest behind always goes to the lowest level;
// we just check that it fits in the level, that DB allows ingest_behind,
// and that we don't have 0 seqnums at the upper levels.
// REQUIRES: Mutex held
Status CheckLevelForIngestedBehindFile(IngestedFileInfo* file_to_ingest);
// Set the file global sequence number to `seqno`
Status AssignGlobalSeqnoForIngestedFile(IngestedFileInfo* file_to_ingest,
SequenceNumber seqno);
// Generate the file checksum and store in the IngestedFileInfo
IOStatus GenerateChecksumForIngestedFile(IngestedFileInfo* file_to_ingest);
// Check if `file_to_ingest` can fit in level `level`
// REQUIRES: Mutex held
bool IngestedFileFitInLevel(const IngestedFileInfo* file_to_ingest,
int level);
// Helper method to sync given file.
template <typename TWritableFile>
Status SyncIngestedFile(TWritableFile* file);
SystemClock* clock_;
FileSystemPtr fs_;
VersionSet* versions_;
ColumnFamilyData* cfd_;
const ImmutableDBOptions& db_options_;
const EnvOptions& env_options_;
SnapshotList* db_snapshots_;
autovector<IngestedFileInfo> files_to_ingest_;
const IngestExternalFileOptions& ingestion_options_;
Directories* directories_;
EventLogger* event_logger_;
VersionEdit edit_;
uint64_t job_start_time_;
int consumed_seqno_count_;
// Set in ExternalSstFileIngestionJob::Prepare(), if true all files are
// ingested in L0
bool files_overlap_{false};
// Set in ExternalSstFileIngestionJob::Prepare(), if true and DB
// file_checksum_gen_factory is set, DB will generate checksum each file.
bool need_generate_file_checksum_{true};
std::shared_ptr<IOTracer> io_tracer_;
};
} // namespace ROCKSDB_NAMESPACE