Hello Bikramjeet Vig, Dan Hecht, I'd like you to reexamine a change. Please visit
http://gerrit.cloudera.org:8080/8631 to look at the new patch set (#2). Change subject: IMPALA-6227: deflake admission stress tests ...................................................................... IMPALA-6227: deflake admission stress tests The problem was that, during the initial admission decision phase, some queries were initially queued then dequeued once memory came available. All of the accounting in the test implicitly relies on queries not being dequeued until queries are later explicitly ended, so if this happened, the test broke in multiple subtle ways. This happened because the query only scanned a small number of rows, which could be all buffered on the receiver side of the exchange even before the client fetched any rows from the coordinator. This means that the reserved memory on some backends could increase then decrease during the initial admission phase, resulting in a query being queued then dequeued. The fix is to increase the number of rows returned by the query so that all fragments remain active during the initial admission phase. This increased test execution time somewhat, so I also had to bump the queue wait timeout for the admission stress tests (they assume that queries don't time out in the queue). Testing: Ran the test under debug, release and ASAN builds, i.e. impala-py.test tests/custom_cluster/test_admission_controller.py \ --workload_exploration_strategy="functional-query:exhaustive" I looped the mem_limit test for a while to confirm it didn't reproduce (it reproduced reliably every 2-3 iterations before this fix). I will try looping it a bit more under different build types concurrently with the review. Change-Id: Iafb3af0ce68f96e5d713dbb3b37dd0b50ea66bb4 --- M fe/src/test/resources/llama-site-test2.xml M tests/custom_cluster/test_admission_controller.py 2 files changed, 89 insertions(+), 47 deletions(-) git pull ssh://gerrit.cloudera.org:29418/Impala-ASF refs/changes/31/8631/2 -- To view, visit http://gerrit.cloudera.org:8080/8631 To unsubscribe, visit http://gerrit.cloudera.org:8080/settings Gerrit-Project: Impala-ASF Gerrit-Branch: master Gerrit-MessageType: newpatchset Gerrit-Change-Id: Iafb3af0ce68f96e5d713dbb3b37dd0b50ea66bb4 Gerrit-Change-Number: 8631 Gerrit-PatchSet: 2 Gerrit-Owner: Tim Armstrong <tarmstr...@cloudera.com> Gerrit-Reviewer: Bikramjeet Vig <bikramjeet....@cloudera.com> Gerrit-Reviewer: Dan Hecht <dhe...@cloudera.com>