Jan Van Besien created HBASE-14205:
--------------------------------------
Summary: RegionCoprocessorHost System.nanoTime() performance
bottleneck
Key: HBASE-14205
URL: https://issues.apache.org/jira/browse/HBASE-14205
Project: HBase
Issue Type: Bug
Reporter: Jan Van Besien
The tracking of execution time of coprocessor methods introduced in HBASE-11516
introduces 2 calls to System.nanoTime() per coprocessor method per coprocessor.
This is resulting in a serious performance bottleneck in certain scenarios.
For example consider the scenario where many rows are being ingested (PUT) in a
table which has multiple coprocessors (we have up to 20 coprocessors). This
results in 8 extra calls to System.nanoTime() per row (prePut, postPut,
postStartRegionOperation and postCloseRegionOperation) which has been seen to
result in a 50% increase of execution time.
I think it is generally considered bad practice to measure execution times on
such a small scale (per single operation). Also note that measurements are
taken even for coprocessors that do not even have an actual implementation for
certain operations, making the problem worse.
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
