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Duo Zhang commented on HBASE-21256: ----------------------------------- Overall LGTM. The only concerns is about the AtomicLong in Random64. > Improve IntegrationTestBigLinkedList for testing huge data > ---------------------------------------------------------- > > Key: HBASE-21256 > URL: https://issues.apache.org/jira/browse/HBASE-21256 > Project: HBase > Issue Type: Improvement > Components: integration tests > Affects Versions: 3.0.0 > Reporter: Zephyr Guo > Assignee: Zephyr Guo > Priority: Major > Fix For: 3.0.0 > > Attachments: HBASE-21256-v1.patch, HBASE-21256-v2.patch, > HBASE-21256-v3.patch, HBASE-21256-v4.patch, ITBLL-1.png, ITBLL-2.png > > > Recently, I use ITBLL to test some features in our company. I have > encountered the following problems: > > 1. Generator is too slow at the generating stage, the root cause is > SecureRandom. There is a global lock in SecureRandom( See the following > picture). I use Random instead of SecureRandom, and it could speed up this > stage(500% up with 20 mapper). SecureRandom was brought by HBASE-13382, but > speaking of generating random bytes, in my opnion, > it is the same with Random. > !ITBLL-1.png! > 2. VerifyReducer have a cpu cost of 14% on format method. This is cause by > create keyString variable. However, keyString may never be used if test > result is correct.(and that's in most cases). Just delay creating keyString > can yield huge performance boost in verifing stage. > !ITBLL-2.png! > 3.Arguments check is needed, because there's constraint between arguments. If > we broken this constraint, we can not get a correct circular list. > > 4.Let big family value size could be configured. > > 5.Avoid starting RS at backup master -- This message was sent by Atlassian JIRA (v7.6.3#76005)