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Hive QA commented on HIVE-17979: -------------------------------- Here are the results of testing the latest attachment: https://issues.apache.org/jira/secure/attachment/12936170/HIVE-17979.3.patch {color:red}ERROR:{color} -1 due to build exiting with an error Test results: https://builds.apache.org/job/PreCommit-HIVE-Build/13334/testReport Console output: https://builds.apache.org/job/PreCommit-HIVE-Build/13334/console Test logs: http://104.198.109.242/logs/PreCommit-HIVE-Build-13334/ Messages: {noformat} Executing org.apache.hive.ptest.execution.TestCheckPhase Tests exited with: Exception: Patch URL https://issues.apache.org/jira/secure/attachment/12936170/HIVE-17979.3.patch was found in seen patch url's cache and a test was probably run already on it. Aborting... {noformat} This message is automatically generated. ATTACHMENT ID: 12936170 - PreCommit-HIVE-Build > Tez: Improve ReduceRecordSource passDownKey copying > --------------------------------------------------- > > Key: HIVE-17979 > URL: https://issues.apache.org/jira/browse/HIVE-17979 > Project: Hive > Issue Type: Improvement > Affects Versions: 3.0.0 > Reporter: Gopal V > Assignee: Gopal V > Priority: Major > Attachments: HIVE-17979.1.patch, HIVE-17979.2.patch, > HIVE-17979.3.patch > > > Tez does not use a single Key stream for both sides of the join, so each > input gets its own ReduceRecordSource > {code} > sources[tag] = new ReduceRecordSource(); > {code} > And this means for each input stream, there's a deserialized key (because the > tag is not part of the Key byte stream), this means for a 2-table join there > are 2 ReduceRecordSource objects. > This means that the passDownKey is only an optimization when the Key, > List<Value> has more than 1 value in it. Otherwise the copy is entirely > wasted CPU cycles, because it deserializes the entire row to extract the key > and discards the row. -- This message was sent by Atlassian JIRA (v7.6.3#76005)