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Rajesh Balamohan resolved HIVE-24710. ------------------------------------- Fix Version/s: 4.0.0 Resolution: Fixed Thanks for the review [~ashutoshc]. Merged the PR. > Optimise PTF iteration for count(*) to reduce CPU and IO cost > ------------------------------------------------------------- > > Key: HIVE-24710 > URL: https://issues.apache.org/jira/browse/HIVE-24710 > Project: Hive > Issue Type: Improvement > Components: HiveServer2 > Reporter: Rajesh Balamohan > Priority: Major > Labels: performance, pull-request-available > Fix For: 4.0.0 > > Time Spent: 0.5h > Remaining Estimate: 0h > > E.g query > {noformat} > select x, y, count(*) over (partition by x order by y range between 86400 > PRECEDING and CURRENT ROW) r0 from foo > {noformat} > 1. In such cases, there is no need to iterate over the rowcontainers often > (internally it does O(n^2) operations taking forever when window frame is > really large). This can be optimised to reduce CPU burn and IO. > 2. BasePartitionEvaluator::calcFunctionValue need not materialize ROW when > parameters are empty. This codepath can also be optimised. -- This message was sent by Atlassian Jira (v8.3.4#803005)