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https://issues.apache.org/jira/browse/HIVE-7195?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14030131#comment-14030131
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Mithun Radhakrishnan commented on HIVE-7195:
--------------------------------------------

[~sershe]: I'm sorry, I've not found the time to port my patch to 13 and raise 
a JIRA. My work was primarily in the PartitionPruner code. It was to ensure 
that {{listPartitions(db, table, -1)}} isn't called (during plan optimization), 
if the call is a metadata-only query. I can post the 12-patch in a JIRA, 
whatever that's worth.

Incidentally, I've raised HIVE-7223 to discuss the idea of using 
{{PartitionSpecs}}. [~alangates] suggested that we explore if a PartitionSpec 
abstract could also represent lighter Partition-groups that share commonality 
(StorageDescs, etc.). Still thinking that through. (If only Thrift supported 
polymorphism. :])

> Improve Metastore performance
> -----------------------------
>
>                 Key: HIVE-7195
>                 URL: https://issues.apache.org/jira/browse/HIVE-7195
>             Project: Hive
>          Issue Type: Improvement
>            Reporter: Brock Noland
>            Priority: Critical
>
> Even with direct SQL, which significantly improves MS performance, some 
> operations take a considerable amount of time, when there are many partitions 
> on table. Specifically I believe the issue:
> * When a client gets all partitions we do not send them an iterator, we 
> create a collection of all data and then pass the object over the network in 
> total
> * Operations which require looking up data on the NN can still be slow since 
> there is no cache of information and it's done in a serial fashion
> * Perhaps a tangent, but our client timeout is quite dumb. The client will 
> timeout and the server has no idea the client is gone. We should use 
> deadlines, i.e. pass the timeout to the server so it can calculate that the 
> client has expired.



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