46516778dd
Summary: The DecreaseNumBgThreads test keeps failing on Windows in AppVeyor. It fails because it depends on a timed wait for the tasks to be dequeued from the threadpool's internal queue, but within the specified time, the task might have not been scheduled onto the newly created threads. https://github.com/facebook/rocksdb/pull/6232 tries to fix this by waiting for longer time to let the threads scheduled. This PR tries to fix this by replacing the timed wait with a synchronization on the task's internal conditional variable. When the number of threads increases, instead of guessing the time needed for the task to be scheduled, it directly blocks on the conditional variable until the task starts running. But when thread number is reduced, it still does a timed wait, but this does not lead to the flakiness now, will try to remove these timed waits in a future PR. Pull Request resolved: https://github.com/facebook/rocksdb/pull/6393 Test Plan: Wait to see whether AppVeyor tests pass. Differential Revision: D19890928 Pulled By: cheng-chang fbshipit-source-id: 4e56e4addf625c98c0876e62d9d57a6f0a156f76
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/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.