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https://issues.apache.org/jira/browse/IMPALA-9317?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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Tim Armstrong resolved IMPALA-9317.
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Fix Version/s: Impala 4.0
Resolution: Fixed
This was fixed as part of IMPALA-9156 in HdfsScanNode.java
> Improve number of instances estimate for scans in planner
> ---------------------------------------------------------
>
> Key: IMPALA-9317
> URL: https://issues.apache.org/jira/browse/IMPALA-9317
> Project: IMPALA
> Issue Type: Improvement
> Components: Frontend
> Reporter: Tim Armstrong
> Assignee: Tim Armstrong
> Priority: Major
> Labels: multithreading
> Fix For: Impala 4.0
>
>
> Currently the number of instances (used for various estimates) is calculated
> as estimated # hosts * mt_dop. This is suboptimal, because in many cases
> there isn't enough input data to allow creating that many instances per host.
> The per-host estimate for scans actually already handles this correctly by
> capping the hosts estimate at the number of input splits - we should use the
> same approach for number of instance estimates.
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