[IMPALA-9584] test_analytic_fns is flaky (small fractional differences in AVG)

• Type: Bug
• Status: Resolved
• Priority: Blocker
• Resolution: Fixed
• Component/s: Backend
• Labels: broken-build flaky-test
• Target Version: Impala 4.0.0
• Epic Color: ghx-label-10
• Assignee: Csaba Ringhofer
• Reporter: Csaba Ringhofer
• Created: 31/Mar/20 15:02
• Updated: 08/Apr/20 15:39
• Resolved: 08/Apr/20 15:39

Description

The issue occurred here:
https://jenkins.impala.io/job/ubuntu-16.04-dockerised-tests/2065/testReport/query_test.test_queries/TestQueries/test_analytic_fns_protocol__hs2___exec_option____batch_size___0___num_nodes___0___disable_codegen_rows_threshold___0___disable_codegen___False___abort_on_error___1___exec_single_node_rows_threshold___0____table_format__parquet_none_/

The same test failed with all protocols.

Failing query:
https://github.com/apache/impala/blob/ebbe52b4bed944d3012e3679dc984827ce11d5a8/testdata/workloads/functional-query/queries/QueryTest/analytic-fns.test#L2

Errors are like (hs2):
2009,3,6,3.666666666666667,2009-03-01 20:12:00.475000,'0','8' != 2009,3,6,3.66666666667,2009-03-01 20:12:00.474999,'0','8'

I think that the problem is not the difference in the 4th double column, as that depends on the client used and we do not require complete match during comparison. So the problem is likely to be the timestamp in the 5th column.

Issue Links

• relates to: IMPALA-7472 Consider removing TimestampValue::FromSubsecondUnixTime