[jira] [Commented] (CASSANDRA-12277) Extend testing infrastructure to handle expected intermittent flaky tests - see ReplicationAwareTokenAllocatorTest.testNewCluster

["Sylvain Lebresne (JIRA)" <ji...@apache.org>]

    [ https://issues.apache.org/jira/browse/CASSANDRA-12277?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15391446#comment-15391446 ] 

Sylvain Lebresne commented on CASSANDRA-12277:
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I'll admit that at face value that seems a weird and potentially dangerous thing to do to me. I can easily see us defaulting to such mechanism every time we get a flaky test and that hiding genuine problems more often than not. I don't know the details about that specific {{ReplicationAwareTokenAllocatorTest.testNewCluster}} test, but if a test knowingly fails a number of the times, this feels to me like the test isn't precise enough and should be improved.

Note that I can buy that exceptionally a test is such that making it pass 100% of the time is too much work to be worth the trouble but the test is still nice to have, but that should be exceptional and I'd rather handle that in a case-by-case basis, with very precise comment as to why this is allowed to fail some of the times, to make it clear it's a special case.   

> Extend testing infrastructure to handle expected intermittent flaky tests - see ReplicationAwareTokenAllocatorTest.testNewCluster
> ---------------------------------------------------------------------------------------------------------------------------------
>
>                 Key: CASSANDRA-12277
>                 URL: https://issues.apache.org/jira/browse/CASSANDRA-12277
>             Project: Cassandra
>          Issue Type: Bug
>            Reporter: Joshua McKenzie
>            Assignee: Branimir Lambov
>            Priority: Minor
>              Labels: test
>
> From an offline discussion:
> bq. The ReplicationAwareTokenAllocatorTest.testNewCluster failure is a flake -- randomness will sometimes (on the order of 1/100) cause it to fail. Extending the ranges to avoid these flakes goes too far and makes the test meaningless.
> bq. How about instead of @flaky/@Ignore which currently indicates a test that intermittently fails but we do not expect it to, we instead use @tries, or @runs, or some annotation that indicates "run this thing N times, if M pass we're good". This would allow us to keep the current "we don't care about these test results (in context of green test board) because intermittent failures are not expected and the test quality needs shoring up" from "we expect this test to fail sometimes in this particular way."



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