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https://issues.apache.org/jira/browse/HIVE-13884?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15319592#comment-15319592
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Sergio Peña commented on HIVE-13884:
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[~hagleitn] [~selinazh] I saw you added the partition limit on HIVE-6492. This
ticket is extending that limit to the metastore to avoid OOM exceptions when
fetching too many partitions. Could you help me reviewing this patch? Or do you
know any other person who understand the metastore too?
> Disallow queries fetching more than a configured number of partitions in
> PartitionPruner
> ----------------------------------------------------------------------------------------
>
> Key: HIVE-13884
> URL: https://issues.apache.org/jira/browse/HIVE-13884
> Project: Hive
> Issue Type: Improvement
> Reporter: Mohit Sabharwal
> Assignee: Sergio Peña
> Attachments: HIVE-13884.1.patch
>
>
> Currently the PartitionPruner requests either all partitions or partitions
> based on filter expression. In either scenarios, if the number of partitions
> accessed is large there can be significant memory pressure at the HMS server
> end.
> We already have a config {{hive.limit.query.max.table.partition}} that
> enforces limits on number of partitions that may be scanned per operator. But
> this check happens after the PartitionPruner has already fetched all
> partitions.
> We should add an option at PartitionPruner level to disallow queries that
> attempt to access number of partitions beyond a configurable limit.
> Note that {{hive.mapred.mode=strict}} disallow queries without a partition
> filter in PartitionPruner, but this check accepts any query with a pruning
> condition, even if partitions fetched are large. In multi-tenant
> environments, admins could use more control w.r.t. number of partitions
> allowed based on HMS memory capacity.
> One option is to have PartitionPruner first fetch the partition names
> (instead of partition specs) and throw an exception if number of partitions
> exceeds the configured value. Otherwise, fetch the partition specs.
> Looks like the existing {{listPartitionNames}} call could be used if extended
> to take partition filter expressions like {{getPartitionsByExpr}} call does.
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