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https://issues.apache.org/jira/browse/ASTERIXDB-1733?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15799739#comment-15799739
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ASF subversion and git services commented on ASTERIXDB-1733:
------------------------------------------------------------

Commit 8b2aceeb97c8f89f2898c0b35f38cc36d3cdda63 in asterixdb's branch 
refs/heads/master from [~wangsaeu]
[ https://git-wip-us.apache.org/repos/asf?p=asterixdb.git;h=8b2acee ]

ASTERIXDB-1556, ASTERIXDB-1733: Hash Group By and Hash Join conform to the 
memory budget

 - External Hash Group By and Hash Join now conform to the memory budget 
(compiler.groupmemory and compiler.joinmemory)
 - For Optimzed Hybrid Hash Join, we calculate the expected hash table size 
when the build phase is done and
   try to spill one or more partitions if the freespace can't afford the hash 
table size.
 - For External Hash Group By, the number of hash entries (hash table size) is 
calculated based on
   an estimation of the aggregated tuple size and possible hash values for the 
given field size in that tuple.
 - Garbage Collection feature has been added to SerializableHashTable. For 
external hash group-by,
   whenever we spill a data partition to the disk, we also check the ratio of 
garbage in the hash table.
   If it's greater than the given threshold, we conduct a GC on Hash Table.

Change-Id: I2b323e9a2141b4c1dd1652a360d2d9354d3bc3f5
Reviewed-on: https://asterix-gerrit.ics.uci.edu/1056
Tested-by: Jenkins <jenk...@fulliautomatix.ics.uci.edu>
BAD: Jenkins <jenk...@fulliautomatix.ics.uci.edu>
Integration-Tests: Jenkins <jenk...@fulliautomatix.ics.uci.edu>
Reviewed-by: Yingyi Bu <buyin...@gmail.com>


> Hash Table used by hash-join doesn't conform to the budget.
> -----------------------------------------------------------
>
>                 Key: ASTERIXDB-1733
>                 URL: https://issues.apache.org/jira/browse/ASTERIXDB-1733
>             Project: Apache AsterixDB
>          Issue Type: Bug
>            Reporter: Taewoo Kim
>            Assignee: Taewoo Kim
>
> The hash table in the hash join doesn't conform to the frame limit 
> (join.memory parameter in the configuration file). This is related to 
> ASTERIXDB-1556.



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