fee2c472d0
Summary: The main purpose is to make debugging easier without sacrificing performance. Instead of using a boolean variable for `CompactionIterator::valid_`, we can extend it to an `uint8_t`, using the LSB to denote if the compaction iterator is valid and 4 additional bits to denote where the iterator is set valid inside `NextFromInput()`. Therefore, when the control flow reaches `PrepareOutput()` and hits assertion there, we can have a better idea of what has gone wrong. Pull Request resolved: https://github.com/facebook/rocksdb/pull/10505 Test Plan: make check ``` TEST_TMPDIR=/dev/shm/rocksdb time ./db_bench -compression_type=none -write_buffer_size=1073741824 -benchmarks=fillseq,flush ``` The above command has a 'flush' benchmark which uses `CompactionIterator`. I haven't observed any CPU regression or drop in throughput or latency increase. Reviewed By: ltamasi Differential Revision: D38551615 Pulled By: riversand963 fbshipit-source-id: 1250848fc118bb753d71fa9ff8ba840df999f5e0
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.