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Yongzhi Chen resolved IMPALA-7637. ---------------------------------- Fix Version/s: Impala 3.4.0 Resolution: Fixed > Include more hash table stats in profile > ---------------------------------------- > > Key: IMPALA-7637 > URL: https://issues.apache.org/jira/browse/IMPALA-7637 > Project: IMPALA > Issue Type: Improvement > Components: Backend > Reporter: Tim Armstrong > Assignee: Yongzhi Chen > Priority: Major > Labels: observability, ramp-up > Fix For: Impala 3.4.0 > > > Our hash table collects some useful stats about collisions and travel length, > but then we don't do anything to expose them: > https://github.com/apache/impala/blob/540611e863fe99b3d3ae35f8b94a745a68b9eba2/be/src/exec/hash-table.h#L989 > We should add some of them to the profile, maybe: > * the number of probes > * the average travel length per probe > * the number of hash collisions > * (optional) the number of hash table resizes. We already have the hash table > size and the resize time, which I think is sufficient to debug most problems > with resizes. -- 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