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https://issues.apache.org/jira/browse/HIVE-12847?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15105603#comment-15105603
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Sergey Shelukhin commented on HIVE-12847:
-----------------------------------------

That is what HBase metastore cache stores right now. I think there are even the 
comments wondering about uniting representation. So that would make sense.

> ORC file footer cache should be memory sensitive
> ------------------------------------------------
>
>                 Key: HIVE-12847
>                 URL: https://issues.apache.org/jira/browse/HIVE-12847
>             Project: Hive
>          Issue Type: Improvement
>          Components: File Formats, ORC
>    Affects Versions: 1.2.1
>            Reporter: Nemon Lou
>            Assignee: Nemon Lou
>         Attachments: HIVE-12847.patch
>
>
> The size based footer cache can not control memory usage properly.
> Having seen a HiveServer2 hang (full GC all the time) due to ORC file footer 
> cache taking up too much heap memory.
> A simple query like "select * from orc_table limit 1" can make HiveServer2 
> hang.
> The input table has about 1000 ORC files and each ORC file owns about 2500 
> stripes.
> {noformat}
>  num     #instances         #bytes  class name
> ----------------------------------------------
>    1:     214653601    25758432120  
> org.apache.hadoop.hive.ql.io.orc.OrcProto$ColumnStatistics
>    3:     122233301     8800797672  
> org.apache.hadoop.hive.ql.io.orc.OrcProto$StringStatistics
>    5:      89439001     6439608072  
> org.apache.hadoop.hive.ql.io.orc.OrcProto$IntegerStatistics
>    7:       2981300      262354400  
> org.apache.hadoop.hive.ql.io.orc.OrcProto$StripeInformation
>    9:       2981300      143102400  
> org.apache.hadoop.hive.ql.io.orc.OrcProto$StripeStatistics
>   12:       2983691       71608584  
> org.apache.hadoop.hive.ql.io.orc.ReaderImpl$StripeInformationImpl
>   15:         80929        7121752  
> org.apache.hadoop.hive.ql.io.orc.OrcProto$Type
>   17:        103282        5783792  
> org.apache.hadoop.mapreduce.lib.input.FileSplit
>   20:         51641        3305024  
> org.apache.hadoop.hive.ql.exec.FetchOperator$FetchInputFormatSplit
>   21:         51641        3305024  org.apache.hadoop.hive.ql.io.orc.OrcSplit
>   31:             1         413152  
> [Lorg.apache.hadoop.hive.ql.exec.FetchOperator$FetchInputFormatSplit;  
>  100:          1122          26928  org.apache.hadoop.hive.ql.io.orc.Metadata 
>  
> {noformat}



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