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Yerui Sun resolved KYLIN-1379. ------------------------------ Resolution: Fixed Fix Version/s: v1.5.3 > More stable and functional precise count distinct implements after KYLIN-1186 > ----------------------------------------------------------------------------- > > Key: KYLIN-1379 > URL: https://issues.apache.org/jira/browse/KYLIN-1379 > Project: Kylin > Issue Type: Improvement > Components: Job Engine > Affects Versions: v1.5.0, v1.3.0 > Reporter: Yerui Sun > Assignee: Yerui Sun > Fix For: v1.5.3 > > > After KYLIN-1186, we've gained the ability to count distinct Int type columns > precisely. > However, the implements of KYLIN-1186 is not stable, especially in > 2.x-staging branch. > The reason is that the measure's maxlength is used to allocate memory in 2.x > version, and the BitmapMeasure is hardcoded to 8MB in KYLIN-1186, causing OOM > when cube building. > To resolve this problem, we have introduce precision on the bitmap measure, > such as bitmap(100), bitmap(10000), bitmap(1000000), meaning the measure > could accept 100/10000/1M cardinality at most. This solution should be fine, > considering the reality, if the count value over 1000000, the hyperloglog > measure which produce approx. result should be acceptable. -- This message was sent by Atlassian JIRA (v6.3.4#6332)