Release RocksDB 6.23.3 · facebook/rocksdb

6.23.3 (2021-08-09)

Removed a call to RenameFile() on a non-existent info log file ("LOG") when opening a new DB. Such a call was guaranteed to fail though did not impact applications since we swallowed the error. Now we also stopped swallowing errors in renaming "LOG" file.
Fixed a bug affecting the batched MultiGet API when used with keys spanning multiple column families and sorted_input == false.

Fixed a race related to the destruction of ColumnFamilyData objects. The earlier logic unlocked the DB mutex before destroying the thread-local SuperVersion pointers, which could result in a process crash if another thread managed to get a reference to the ColumnFamilyData object.
Fixed an issue where OnFlushCompleted was not called for atomic flush.

Obsolete keys in the bottommost level that were preserved for a snapshot will now be cleaned upon snapshot release in all cases. This form of compaction (snapshot release triggered compaction) previously had an artificial limitation that multiple tombstones needed to be present.

Blob file checksums are now printed in hexadecimal format when using the manifest_dump ldb command.
GetLiveFilesMetaData() now populates the temperature, oldest_ancester_time, and file_creation_time fields of its LiveFileMetaData results when the information is available. Previously these fields always contained zero indicating unknown.
Fix mismatches of OnCompaction{Begin,Completed} in case of DisableManualCompaction().
Fix continuous logging of an existing background error on every user write
Fix a bug that Get() return Status::OK() and an empty value for non-existent key when read_options.read_tier = kBlockCacheTier.
Fix a bug that stat in get_context didn't accumulate to statistics when query is failed.

ldb has a new feature, list_live_files_metadata, that shows the live SST files, as well as their LSM storage level and the column family they belong to.
The new BlobDB implementation now tracks the amount of garbage in each blob file in the MANIFEST.
Integrated BlobDB now supports Merge with base values (Put/Delete etc.).
RemoteCompaction supports sub-compaction, the job_id in the user interface is changed from int to uint64_t to support sub-compaction id.
Expose statistics option in RemoteCompaction worker.

Added APIs to the Customizable class to allow developers to create their own Customizable classes. Created the utilities/customizable_util.h file to contain helper methods for developing new Customizable classes.
Change signature of SecondaryCache::Name(). Make SecondaryCache customizable and add SecondaryCache::CreateFromString method.