mirror of https://github.com/facebook/rocksdb.git
3dff28cf9b
Summary: For performance purposes, the lower level routines were changed to use a SystemClock* instead of a std::shared_ptr<SystemClock>. The shared ptr has some performance degradation on certain hardware classes. For most of the system, there is no risk of the pointer being deleted/invalid because the shared_ptr will be stored elsewhere. For example, the ImmutableDBOptions stores the Env which has a std::shared_ptr<SystemClock> in it. The SystemClock* within the ImmutableDBOptions is essentially a "short cut" to gain access to this constant resource. There were a few classes (PeriodicWorkScheduler?) where the "short cut" property did not hold. In those cases, the shared pointer was preserved. Using db_bench readrandom perf_level=3 on my EC2 box, this change performed as well or better than 6.17: 6.17: readrandom : 28.046 micros/op 854902 ops/sec; 61.3 MB/s (355999 of 355999 found) 6.18: readrandom : 32.615 micros/op 735306 ops/sec; 52.7 MB/s (290999 of 290999 found) PR: readrandom : 27.500 micros/op 871909 ops/sec; 62.5 MB/s (367999 of 367999 found) (Note that the times for 6.18 are prior to revert of the SystemClock). Pull Request resolved: https://github.com/facebook/rocksdb/pull/8033 Reviewed By: pdillinger Differential Revision: D27014563 Pulled By: mrambacher fbshipit-source-id: ad0459eba03182e454391b5926bf5cdd45657b67 |
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| .. | ||
| file_read_sample.h | ||
| histogram.cc | ||
| histogram.h | ||
| histogram_test.cc | ||
| histogram_windowing.cc | ||
| histogram_windowing.h | ||
| in_memory_stats_history.cc | ||
| in_memory_stats_history.h | ||
| instrumented_mutex.cc | ||
| instrumented_mutex.h | ||
| iostats_context.cc | ||
| iostats_context_imp.h | ||
| iostats_context_test.cc | ||
| perf_context.cc | ||
| perf_context_imp.h | ||
| perf_level.cc | ||
| perf_level_imp.h | ||
| perf_step_timer.h | ||
| persistent_stats_history.cc | ||
| persistent_stats_history.h | ||
| statistics.cc | ||
| statistics.h | ||
| statistics_test.cc | ||
| stats_history_test.cc | ||
| thread_status_impl.cc | ||
| thread_status_updater.cc | ||
| thread_status_updater.h | ||
| thread_status_updater_debug.cc | ||
| thread_status_util.cc | ||
| thread_status_util.h | ||
| thread_status_util_debug.cc | ||