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Hive QA commented on HIVE-20983: -------------------------------- Here are the results of testing the latest attachment: https://issues.apache.org/jira/secure/attachment/12980217/HIVE-20983.3.patch {color:green}SUCCESS:{color} +1 due to 7 test(s) being added or modified. {color:red}ERROR:{color} -1 due to 1 failed/errored test(s), 16753 tests executed *Failed tests:* {noformat} org.apache.hadoop.hive.llap.cache.TestBuddyAllocator.testMTT[2] (batchId=361) {noformat} Test results: https://builds.apache.org/job/PreCommit-HIVE-Build/18593/testReport Console output: https://builds.apache.org/job/PreCommit-HIVE-Build/18593/console Test logs: http://104.198.109.242/logs/PreCommit-HIVE-Build-18593/ Messages: {noformat} Executing org.apache.hive.ptest.execution.TestCheckPhase Executing org.apache.hive.ptest.execution.PrepPhase Executing org.apache.hive.ptest.execution.YetusPhase Executing org.apache.hive.ptest.execution.ExecutionPhase Executing org.apache.hive.ptest.execution.ReportingPhase Tests exited with: TestsFailedException: 1 tests failed {noformat} This message is automatically generated. ATTACHMENT ID: 12980217 - PreCommit-HIVE-Build > Vectorization: Scale up small hashtables, when collisions are detected > ---------------------------------------------------------------------- > > Key: HIVE-20983 > URL: https://issues.apache.org/jira/browse/HIVE-20983 > Project: Hive > Issue Type: Bug > Reporter: Gopal V > Assignee: Mustafa Iman > Priority: Major > Labels: pull-request-available > Attachments: HIVE-20983.1.patch, HIVE-20983.2.patch, > HIVE-20983.3.patch > > Time Spent: 10m > Remaining Estimate: 0h > > Hive's hashtable estimates are getting better with HyperLogLog stats in > place, but an accurate estimate does not always result in a low number of > collisions. > The hashtables which contain a very small number of items tend to lose their > O(1) lookup performance where there are collisions. Since collisions are easy > to detect within the fast hashtable implementation, a rehashing to a higher > size will help these small hashtables avoid collisions and go back to O(1) > perf. -- This message was sent by Atlassian Jira (v8.3.2#803003)