[
https://issues.apache.org/jira/browse/HBASE-16205?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15376523#comment-15376523
]
binlijin commented on HBASE-16205:
----------------------------------
[~anoop.hbase], sir
With MSLAB turn on. What i am suggest is:
One case: a request with two cell: cell1=100k, cell2=100k, cell1+cell2<256K so
cell1 and cell2 copy to MSLAB.
Two case: a request with two cell: cell1=200k, cell2=100k, cell1+cell2>256K,
cell1 and cell2 do not copy to MSLAB.
Three case: a request with two cell: cell1=300k, cell2=1k, cell2>256K, cell1
and cell2 do not copy to MSLAB.
And the two and three case is what i am suggested.
> When Cells are not copied to MSLAB, deep clone it while adding to Memstore
> --------------------------------------------------------------------------
>
> Key: HBASE-16205
> URL: https://issues.apache.org/jira/browse/HBASE-16205
> Project: HBase
> Issue Type: Sub-task
> Components: regionserver
> Affects Versions: 2.0.0
> Reporter: Anoop Sam John
> Assignee: Anoop Sam John
> Priority: Critical
> Fix For: 2.0.0
>
> Attachments: HBASE-16205.patch
>
>
> This is imp after HBASE-15180 optimization. After that we the cells flowing
> in write path will be backed by the same byte[] where the RPC read the
> request into. By default we have MSLAB On and so we have a copy operation
> while adding Cells to memstore. This copy might not be there if
> 1. MSLAB is turned OFF
> 2. Cell size is more than a configurable max size. This defaults to 256 KB
> 3. If the operation is Append/Increment.
> In such cases, we should just clone the Cell into a new byte[] and then add
> to memstore. Or else we keep referring to the bigger byte[] chunk for longer
> time.
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
