Summary: Pull Request resolved: https://github.com/facebook/rocksdb/pull/14947 Teaches the shared `CopyEngine` to hard-link files through its background pool: adds `WorkItemType::Link` and `CopyEngine::LinkFile(src, dst, dst_env)`, which returns the FileSystem's `NotSupported` when links are unavailable so callers can fall back to copying. This is what CheckpointEngine (next diff) needs for warm storage, where linking is supported but benefits from parallelism. No existing caller links through the engine yet (BackupEngine never hard-links), so no behavior change; the path is exercised by a new `copy_engine_test.cc` (parallel copy, parallel link, single-thread copy, per-item error reporting). Reviewed By: xingbowang Differential Revision: D111387972 fbshipit-source-id: ec0b0e9b80749a3f51e62066ceef2df21a1811d2
RocksDB: A Persistent Key-Value Store for Flash and RAM Storage
RocksDB is developed and maintained by Facebook Database Engineering Team. It is built on earlier work on LevelDB by Sanjay Ghemawat (sanjay@google.com) and Jeff Dean (jeff@google.com)
This code is a library that forms the core building block for a fast key-value server, especially suited for storing data on flash drives. It has a Log-Structured-Merge-Database (LSM) design with flexible tradeoffs between Write-Amplification-Factor (WAF), Read-Amplification-Factor (RAF) and Space-Amplification-Factor (SAF). It has multi-threaded compactions, making it especially suitable for storing multiple terabytes of data in a single database.
Start with example usage here: https://github.com/facebook/rocksdb/tree/main/examples
See the github wiki for more explanation.
The public interface is in include/. Callers should not include or
rely on the details of any other header files in this package. Those
internal APIs may be changed without warning.
Questions and discussions are welcome on the RocksDB Developers Public Facebook group and email list on Google Groups.
License
RocksDB is dual-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). You may select, at your option, one of the above-listed licenses.