Hui Xiao
24952ff088
Summary: **Context/Summary:** For users who are interested in knowing how efficient their compaction in reducing L0 files or how bad their long-running compaction in "locking" L0 files, they now have a reference point "L0 files in the CF pre compaction" for their input compaction files. - Compared to the existing stats or exposing in some other way, exposing this info in CompactionJobInfo allows users to compare it with other compaction data (e.g, compaction input num, compaction reason) of within **one** compaction (of per-compaction granularity). - If this number is high while their "short-running" compaction has little L0 files input, then those compaction may have a room for improvement. Similar for those long-running compaction. This PR is to add a new field `CompactionJobInfo::num_l0_files_pre_compaction` for that. Pull Request resolved: https://github.com/facebook/rocksdb/pull/13462 Test Plan: - Piggyback on an existing test Reviewed By: jaykorean Differential Revision: D71124938 Pulled By: hx235 fbshipit-source-id: aa47c9c86c62d9425771b320f5636e50671fd289
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.