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liyang commented on KYLIN-1832: ------------------------------- I see the improvement mainly comes from the added {{biggerIndexSet}} and {{isOverThreshold}}. However I'm bit concerned about the memory footprint introduced by {{biggerIndexSet}}. > HyperLogLog speed is too slow in encode and decode > -------------------------------------------------- > > Key: KYLIN-1832 > URL: https://issues.apache.org/jira/browse/KYLIN-1832 > Project: Kylin > Issue Type: Improvement > Components: Metadata > Affects Versions: v1.3.0, v1.5.2 > Reporter: fengYu > Assignee: fengYu > Attachments: HyperLogLogPlusCounter.java > > > We have a cube with more than ten distinct count measure, and use hll15 store > the value, we found it is too slow of HyperLogLogPlusCounter, there are three > methods will called frequentlly: merge/writeRegisters/readRegisters. > I found in kylin-1.5.x add a parameter 'singleBucket' to store the only one > bucket which can optimize base cuboid. > However, in other step of cuboid building, it will slow down. I has modify > the code to speed up the speed of three operation. -- This message was sent by Atlassian JIRA (v6.3.4#6332)