06b37eef7b
Summary: **Summary**: Set defaults for high-pri and low-pri thread pools in regression test script. **Reason for this change**: With #2680 , high-pri and low-pri thread pools get different numbers than before if `num_high_pri_threads` and `num_low_pri_threads` options are not explicitly passed to db_bench in regression test script ... leading to a false-positive regression. **Test Plan**: REMOTE_HOST=udb1671.prn3 TEST_MODE=1 FBSOURCE=~/fbsource ~/fbsource/fbcode/rocks/tools/debug_regression_test.sh viewstate (with very minor changes to the internals). Observe P50 and P99 which showed up as regressions in our graphs. Stats with the commit prior to #2680 , ie. 4f81ab3 : seekrandomwhilewriting : 75.096 micros/op 13316 ops/sec; 168.6 MB/s (7499074 of 7500000 found) Microseconds per seek: Count: 120000000 Average: 1197.7254 StdDev: 33.35 Min: 187 Median: 980.5292 Max: 1816424 Percentiles: **P50: 980.53** P75: 1494.57 **P99: 4185.64** P99.9: 7800.11 P99.99: 15039.64 Stats at #2680, ie. at commit dce6d5a (false-positive regression): seekrandomwhilewriting : 85.330 micros/op 11719 ops/sec; 148.4 MB/s (7499073 of 7500000 found) Microseconds per seek: Count: 120000000 Average: 1362.3261 StdDev: 27.86 Min: 185 Median: 1088.1915 Max: 652760 Percentiles: **P50: 1088.19** P75: 1658.12 **P99: 5361.15** P99.9: 7997.95 P99.99: 11730.07 Stats with the current change on top of dce6d5a : seekrandomwhilewriting : 77.780 micros/op 12856 ops/sec; 162.8 MB/s (7499102 of 7500000 found) Microseconds per seek: Count: 120000000 Average: 1226.6744 StdDev: 17.16 Min: 185 Median: 994.2956 Max: 2553530 Percentiles: **P50: 994.30** P75: 1513.68 **P99: 4284.30** P99.9: 9338.64 P99.99: 23008.86 Closes https://github.com/facebook/rocksdb/pull/2801 Differential Revision: D5742338 Pulled By: sagar0 fbshipit-source-id: cc5d727c1a131f2a7070d1bb892efbe929b976ff
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/