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ASF subversion and git services commented on IMPALA-6984: --------------------------------------------------------- Commit c413f9b558d51de877f497590baf14139ad5cf99 in impala's branch refs/heads/master from Joe McDonnell [ https://gitbox.apache.org/repos/asf?p=impala.git;h=c413f9b ] IMPALA-10047: Revert core piece of IMPALA-6984 Performance testing on TPC-DS found a peformance regression on short queries due to delayed exec status reports. Further testing traced this back to IMPALA-6984's behavior of cancelling backends on EOS. The coordinator log show that CancelBackends() call intermittently taking 10 seconds due to timing out in the RPC layer. As a temporary workaround, this reverts the core part of IMPALA-6984 that added that CancelBackends() call for EOS. It leaves the rest of IMPALA-6984 intact, as other code has built on top of it. Testing: - Core job - Performance tests Change-Id: Ibf00a56e91f0376eaaa552e3bb4763501bfb49e8 (cherry picked from commit b91f3c0e064d592f3cdf2a2e089ca6546133ba55) Reviewed-on: http://gerrit.cloudera.org:8080/16288 Reviewed-by: Joe McDonnell <joemcdonn...@cloudera.com> Tested-by: Impala Public Jenkins <impala-public-jenk...@cloudera.com> > Coordinator should cancel backends when returning EOS > ----------------------------------------------------- > > Key: IMPALA-6984 > URL: https://issues.apache.org/jira/browse/IMPALA-6984 > Project: IMPALA > Issue Type: Sub-task > Components: Backend > Affects Versions: Impala 3.0 > Reporter: Daniel Hecht > Assignee: Tim Armstrong > Priority: Major > Labels: query-lifecycle > Fix For: Impala 4.0 > > > Currently, the Coordinator waits for backends rather than proactively > cancelling them in the case of hitting EOS. There's a tangled mess that makes > it tricky to proactively cancel the backends related to how > {{Coordinator::ComputeQuerySummary()}} works – we can't update the summary > until the profiles are no longer changing (which also makes sense given that > we want the exec summary to be consistent with the final profile). But we > current tie together the FIS status and the profile, and cancellation of > backends causes the FIS to return CANCELLED, which then means that the > remaining FIS on that backend won't produce a final profile. > With the rework of the protocol for IMPALA-2990 we should make it possible to > sort this out such that a final profile can be requested regardless of how a > FIS ends execution. > This also relates to IMPALA-5783. -- This message was sent by Atlassian Jira (v8.3.4#803005) --------------------------------------------------------------------- To unsubscribe, e-mail: issues-all-unsubscr...@impala.apache.org For additional commands, e-mail: issues-all-h...@impala.apache.org