hbase-issues mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Anoop Sam John (JIRA)" <j...@apache.org>
Subject [jira] [Commented] (HBASE-16438) Create a cell type so that chunk id is embedded in it
Date Thu, 20 Oct 2016 08:53:58 GMT

    [ https://issues.apache.org/jira/browse/HBASE-16438?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15591255#comment-15591255

Anoop Sam John commented on HBASE-16438:

It might be better if this is a new Cell type with a new interface implemented. 
This is needed in another place as well.
When we upsert cell into Memstore, we will remove the cells which is newly added cells mask
out.  And as part of that we will adjust the memstore size (region level as well as global).
 Here we just reduce the size of the removed cell now.  But we cannot do that blindly.  When
this removed cell is having its data bytes in MSLAB, we are not really freeing up those MSLAB
chunk bytes.  Means the cell data size part is still not reduced!  We just got rid of one
Java object. So only that object's overhead part got reduced.  Right now there is no way to
make this diff.  When the cell can be removed, we can not know whether it is having its data
in MSLAB chunk or not.   Once this jira is solved, we can do that also.

> Create a cell type so that chunk id is embedded in it
> -----------------------------------------------------
>                 Key: HBASE-16438
>                 URL: https://issues.apache.org/jira/browse/HBASE-16438
>             Project: HBase
>          Issue Type: Sub-task
>    Affects Versions: 2.0.0
>            Reporter: ramkrishna.s.vasudevan
>            Assignee: ramkrishna.s.vasudevan
> For CellChunkMap we may need a cell such that the chunk out of which it was created,
the id of the chunk be embedded in it so that when doing flattening we can use the chunk id
as a meta data. More details will follow once the initial tasks are completed. 

This message was sent by Atlassian JIRA

View raw message