8d7bc76f36
Summary: There is a race condition in DBFlushTest.SyncFail, as illustrated below. ``` time thread1 bg_flush_thread | Flush(wait=false, cfd) | refs_before=cfd->current()->TEST_refs() PickMemtable calls cfd->current()->Ref() V ``` The race condition between thread1 getting the ref count of cfd's current version and bg_flush_thread incrementing the cfd's current version makes it possible for later assertion on refs_before to fail. Therefore, we add test sync points to enforce the order and assert on the ref count before and after PickMemtable is called in bg_flush_thread. Pull Request resolved: https://github.com/facebook/rocksdb/pull/4633 Differential Revision: D12967131 Pulled By: riversand963 fbshipit-source-id: a99d2bacb7869ec5d8d03b24ef2babc0e6ae1a3b
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 specially suitable for storing multiple terabytes of data in a single database.
Start with example usage here: https://github.com/facebook/rocksdb/tree/master/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.
Design discussions are conducted in https://www.facebook.com/groups/rocksdb.dev/
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.