facebook/rocksdb v11.8.0

on GitHub

11.8.0 (07/28/2026)

Public API Changes

• Add callback-based asynchronous read APIs, DB::GetAsync() and DB::MultiGetAsync(). The idea is that when IO is required, RocksDB can suspend its internal coroutine read path, allowing the read executor thread to do other work. When the IO is complete, RocksDB invokes the user callback. This requires filesystem support for full performance benefits. A new filesystem API FSRandomAccessFile::SubmitReadAsync() is introduced for this. Unlike ReadAsync, the filesystem is responsible for eventually calling the callback. FileSystem::GetReadExecutor() returns the IO executor whose EventBases run coroutine read processing. In the Posix filesystem, an IO-uring based event loop is used to complete the IO.
• Added FlushOptions::listener_wait (default false). When set together with FlushOptions::wait == true, DB::Flush() will not return until the registered EventListener::OnFlushCompleted callbacks for the flushed memtables have finished running. By default (false), Flush(wait=true) may return as soon as the flush result is committed, which can be before (or while) the OnFlushCompleted callbacks execute on the background flush thread. Also added the corresponding C API rocksdb_flushoptions_set_listener_wait() / rocksdb_flushoptions_get_listener_wait().
• Deprecated PinnableWideColumns::serialized_size() in favor of the new PinnableWideColumns::payload_size(), which returns the total size of the columns' names and values (for a plain value this equals the value size). Relatedly, wide-column read accounting changed subtly: read statistics for entities (BYTES_READ, BYTES_PER_READ, and the per-key byte counts for GetEntity/MultiGetEntity) and the ReadOptions::value_size_soft_limit threshold now measure entities by this payload size instead of the serialized entity size. This drops serialization framing bytes from those measurements (so reported/limited sizes for entity reads are slightly smaller than before) and makes plain-value and wide-column accounting consistent.

Behavior Changes

• ReadOptions::value_size_soft_limit now also bounds the blob values resolved from pre-flush blob direct write references during MultiGet/MultiGetEntity (previously these were resolved after the limit check and read without bound). Enforcement is "always make progress": at least one key is read even if its value alone exceeds the limit, and only once the returned size exceeds the limit do subsequent keys get Status::Aborted -- so a caller retrying the aborted keys cannot loop forever on a single value that by itself exceeds the limit.

Performance Improvements

• Reduced copying when reading wide-column entities that have blob-referenced columns, whether stored in separate blob files or embedded (same-file) as blob records in the same SST. On the point-lookup (GetEntity/MultiGetEntity) and blob-backed memtable/direct-write read paths, resolving these columns no longer re-serializes the whole entity into a fresh buffer: inline columns are referenced in place in the pinned entity and each resolved blob value is referenced in place from its fetched buffer. This is enabled by an internal change to PinnableWideColumns that lets its columns reference multiple backing buffers.