090c78a0d7
Summary: Background activities like compaction can negatively affect latency of higher-priority tasks like request processing. To avoid this, rocksdb already lowers the IO priority of background threads on Linux systems. While this takes care of typical IO-bound systems, it does not help much when CPU (temporarily) becomes the bottleneck. This is especially likely when using more expensive compression settings. This patch adds an API to allow for lowering the CPU priority of background threads, modeled on the IO priority API. Benchmarks (see below) show significant latency and throughput improvements when CPU bound. As a result, workloads with some CPU usage bursts should benefit from lower latencies at a given utilization, or should be able to push utilization higher at a given request latency target. A useful side effect is that compaction CPU usage is now easily visible in common tools, allowing for an easier estimation of the contribution of compaction vs. request processing threads. As with IO priority, the implementation is limited to Linux, degrading to a no-op on other systems. Closes https://github.com/facebook/rocksdb/pull/3763 Differential Revision: D7740096 Pulled By: gwicke fbshipit-source-id: e5d32373e8dc403a7b0c2227023f9ce4f22b413c |
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| .. | ||
| env_basic_test.cc | ||
| env_chroot.cc | ||
| env_chroot.h | ||
| env_encryption.cc | ||
| env_hdfs.cc | ||
| env_posix.cc | ||
| env_test.cc | ||
| env.cc | ||
| io_posix.cc | ||
| io_posix.h | ||
| mock_env_test.cc | ||
| mock_env.cc | ||
| mock_env.h | ||
| posix_logger.h | ||