Thomas Tauber-Marshall has posted comments on this change. Change subject: IMPALA-5167: Reduce the number of Kudu clients created (FE) ......................................................................
Patch Set 3: So the GVO failed because there's a custom cluster test that runs impala with a very short (1ms) timeout for Kudu operations and then runs two queries, each of which it expects to timeout while retrieving table metadata. Since we reuse clients now, the metadata ends up being fetched by the first query (even though the operation times out, it apparently still completes afterwards) and then the second query doesn't time out since the metadata is already preset (both tests currently touch the same table, but changing the second one to a different table doesn't seem to fix the problem, presumably the Kudu client loads more tables than explicitly requested). Some possible solutions: - Only run one of the queries. This would cause some coverage to be lost (we could replace it by adding a test that checks for timeout behavior in the BE, which I don't think currently exists, and would work since the BE and FE still use different clients) - Run both of the tests in separate custom_cluster tests. custom_cluster tests are expensive (this one runs for ~20s) so it seems like a lot of test overhead for little benefit. - Provide some way to invalidate the Kudu clients, eg. have 'invalidate metadata' clear the list of clients in KuduUtil. We may want to do something like this anyways since in the current version of the patch once a KuduClient is created for a particular Kudu master, that client will live on as long as the impalad does, and if something goes wrong (eg. the automatic token refresh that the Kudu team implemented doesn't work for some reason) you're basically screwed and won't be able to do anything with that Kudu master without restarting the impalad. -- To view, visit http://gerrit.cloudera.org:8080/6898 To unsubscribe, visit http://gerrit.cloudera.org:8080/settings Gerrit-MessageType: comment Gerrit-Change-Id: I9b0b346f37ee43f7f0eefe34a093eddbbdcf2a5e Gerrit-PatchSet: 3 Gerrit-Project: Impala-ASF Gerrit-Branch: master Gerrit-Owner: Thomas Tauber-Marshall <tmarsh...@cloudera.com> Gerrit-Reviewer: Impala Public Jenkins Gerrit-Reviewer: Marcel Kornacker <marc...@gmail.com> Gerrit-Reviewer: Matthew Jacobs <m...@cloudera.com> Gerrit-Reviewer: Thomas Tauber-Marshall <tmarsh...@cloudera.com> Gerrit-HasComments: No
