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https://issues.apache.org/jira/browse/KYLIN-3905?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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Shaofeng SHI resolved KYLIN-3905.
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Resolution: Fixed
Excellent, thank you xiaoxiang!
> Enable shrunken dictionary default
> ----------------------------------
>
> Key: KYLIN-3905
> URL: https://issues.apache.org/jira/browse/KYLIN-3905
> Project: Kylin
> Issue Type: Improvement
> Components: Measure - Count Distinct
> Reporter: XiaoXiang Yu
> Assignee: XiaoXiang Yu
> Priority: Minor
> Fix For: v2.6.2
>
> Attachments: image-2019-03-25-11-26-59-198.png,
> image-2019-03-25-11-27-26-149.png, image-2019-03-25-11-27-46-175.png,
> image-2019-03-25-11-28-14-256.png, image-2019-03-25-11-29-19-383.png
>
>
> In dev mail list's discussion, I suggest to enable shrunken dictionary by
> default, and received some dev's aggrement.
> When using bitmap measure on a large cardinality column(require global
> dictionaty), build base cuboid step need frequent cache swap so it cannot
> finished within a reasonable period.
> When shrunken dictionary enabled, a new step will be added to build
> separated dictionary for each `InputSplit`, Mapper of **BuildBaseCuboid**
> step only has to fetch a smaller dictionary for itself, instead of a larger
> global dictionary. It will reduce cache swap and make **BuildBaseCuboid**
> step run as quicker as possible.
>
> http://mail-archives.apache.org/mod_mbox/kylin-dev//201903.mbox/%[email protected]%3e
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