[
https://issues.apache.org/jira/browse/TRAFODION-2733?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16165052#comment-16165052
]
ASF GitHub Bot commented on TRAFODION-2733:
-------------------------------------------
Github user selvaganesang commented on a diff in the pull request:
https://github.com/apache/incubator-trafodion/pull/1228#discussion_r138695477
--- Diff: core/sql/cli/Context.h ---
@@ -505,6 +519,8 @@ class ContextCli : public ExGod {
// It points to a list of 'black box' of data allocated by user and is
returned
// back whenever this context is in use.
HashQueue * trafSElist_;
+ // memory quota allocation given back by BMOs to be used by other BMOs
+ ULng32 unusedBMOsMemoryQuota_;
--- End diff --
It is in MB.
> Provide an improved memory quota assignment for big memory operators (BMO)
> --------------------------------------------------------------------------
>
> Key: TRAFODION-2733
> URL: https://issues.apache.org/jira/browse/TRAFODION-2733
> Project: Apache Trafodion
> Issue Type: Improvement
> Components: sql-cmp, sql-exe
> Affects Versions: 2.3-incubating
> Reporter: Selvaganesan Govindarajan
> Assignee: Selvaganesan Govindarajan
> Fix For: 2.3-incubating
>
>
> The big memory operators in Trafodion are HashJoin, HashGroupBy and Sort.
> Trafodion deploys multiple executor server processes (ESPs) to execute a
> query via its data flow architecture. Each ESPs can have an instance of this
> BMO operator. Currently, each instance of this operator can potentially have
> memory quota of 800 MB assigned to do its BMO operation. However, the memory
> allocation is usually limited by the memory pressure when this BMO attempts
> to allocate memory within the assigned quota. The assignment doesn't depend
> upon the estimation of memory needed by this operation.
> Improvement needed in BMO memory assignment are:
> 1. Limit the memory quota assignment for these BMO operations per node
> 2. Memory quota assigned taking into consideration estimated memory needed
> at every operator.
> 3. Ensure that the BMO gets the minimum memory needed at least to function
> smoothly
--
This message was sent by Atlassian JIRA
(v6.4.14#64029)
