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https://issues.apache.org/jira/browse/KYLIN-3905?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16800379#comment-16800379
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XiaoXiang Yu commented on KYLIN-3905:
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h3. Return time statistics of global dictionary(without Shrunken Dictionary)
!image-2019-03-25-11-29-19-383.png!
> Enable shrunken dictionary default
> ----------------------------------
>
> Key: KYLIN-3905
> URL: https://issues.apache.org/jira/browse/KYLIN-3905
> Project: Kylin
> Issue Type: Improvement
> Reporter: XiaoXiang Yu
> Assignee: XiaoXiang Yu
> Priority: Minor
> 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
>
>
> 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.
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