Generalize BackupEngine naming option for share_files_with_checksum SSTs and revert BackupEngine::VerifyBackup to check only file sizes by default (#7032)
Summary:
`bool BackupableDBOptions::new_naming_for_backup_files` is updated to `BackupTableNameOption BackupableDBOptions::share_files_with_checksum_naming`, where `BackupTableNameOption` is an `enum` type with two enumerators `kChecksumAndFileSize` and `kChecksumAndFileSize`. This opens up possibilities of extenting the current naming scheme for backup table files. By default, `BackupTableNameOption BackupableDBOptions::share_files_with_checksum_naming` is set to `kChecksumAndDbSessionId`.
Revert `BackupEngine::VerifyBackup` to only check file sizes by default.
Also fix the construction of the `SstFileDumper` in `GetFileDbIdentities` by setting a proper `Env` of the `Options` passed in the constructor.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/7032
Test Plan: make check
Reviewed By: ajkr
Differential Revision: D22237763
Pulled By: gg814
fbshipit-source-id: 466902a4e731babd64e30f0e82ca1aa82962e52e
main
Zitan Chen5 years agocommitted byFacebook GitHub Bot
* `DB::GetDbSessionId(std::string& session_id)` is added. `session_id` stores a unique identifier that gets reset every time the DB is opened. This DB session ID should be unique among all open DB instances on all hosts, and should be unique among re-openings of the same or other DBs. This identifier is recorded in the LOG file on the line starting with "DB Session ID:".
* `DB::OpenForReadOnly()` now returns `Status::NotFound` when the specified DB directory does not exist. Previously the error returned depended on the underlying `Env`. This change is available in all 6.11 releases as well.
* A parameter `verify_with_checksum` is added to `BackupEngine::VerifyBackup`, which is true by default. So now`BackupEngine::VerifyBackup` verifies checksums and file sizes of backup files by default. Pass `false` for `verify_with_checksum` to maintain the previous behavior and performance of `BackupEngine::VerifyBackup`, by only verifying sizes of backup files.
* A parameter `verify_with_checksum` is added to `BackupEngine::VerifyBackup`, which is false by default. If it is ture,`BackupEngine::VerifyBackup` verifies checksums and file sizes of backup files. Pass `false` for `verify_with_checksum` to maintain the previous behavior and performance of `BackupEngine::VerifyBackup`, by only verifying sizes of backup files.
### New Features
* DB identity (`db_id`) and DB session identity (`db_session_id`) are added to table properties and stored in SST files. SST files generated from SstFileWriter and Repairer have DB identity “SST Writer” and “DB Repairer”, respectively. Their DB session IDs are generated in the same way as `DB::GetDbSessionId`. The session ID for SstFileWriter (resp., Repairer) resets every time `SstFileWriter::Open` (resp., `Repairer::Run`) is called.
* Added experimental option BlockBasedTableOptions::optimize_filters_for_memory for reducing allocated memory size of Bloom filters (~10% savings with Jemalloc) while preserving the same general accuracy. To have an effect, the option requires format_version=5 and malloc_usable_size. Enabling this option is forward and backward compatible with existing format_version=5.
* `BackupableDBOptions::new_naming_for_backup_files` is added. This option is true by default. When it is true, backup table filenames are of the form `<file_number>_<crc32c>_<db_session_id>.sst` as opposed to `<file_number>_<crc32c>_<file_size>.sst`. When there is no `db_session_id` available in the table file, we use `file_size` as a fallback. Note that when this option is true, it comes into effect only when both `share_files_with_checksum` and `share_table_files` are true.
* Added compaction filter support for BlobDB non-TTL values. Same as vanilla RocksDB, user compaction filter applies to all k/v pairs of the compaction for non-TTL values. It honors `min_blob_size`, which potentially results value transitions between inlined data and stored-in-blob data when size of value is changed.
* `BackupTableNameOption BackupableDBOptions::share_files_with_checksum_naming` is added, where `BackupTableNameOption` is an `enum` type with two enumerators `kChecksumAndFileSize` and `kChecksumAndFileSize`. By default, `BackupTableNameOption BackupableDBOptions::share_files_with_checksum_naming` is set to `kChecksumAndDbSessionId`. In this default case, backup table filenames are of the form `<file_number>_<crc32c>_<db_session_id>.sst` as opposed to `<file_number>_<crc32c>_<file_size>.sst`. The new default behavior fixes the backup file name collision problem, which might be possible at large scale, but the option `kChecksumAndFileSize` is added to allow use of old naming in case it is needed. This default behavior change is not an upgrade issue, because previous versions of RocksDB can read, restore, and delete backups using new names, and it's OK for a backup directory to use a mixture of table file naming schemes. Note that `share_files_with_checksum_naming` comes into effect only when both `share_files_with_checksum` and `share_table_files` are true.
### Bug Fixes
* Fail recovery and report once hitting a physical log record checksum mismatch, while reading MANIFEST. RocksDB should not continue processing the MANIFEST any further.
Zitan Chen
5 years ago
committed by