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https://issues.apache.org/jira/browse/HBASE-16205?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15376411#comment-15376411
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Anoop Sam John commented on HBASE-16205:
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Yes when the Cell's length is big then MSLAB copy won't happen.
{code}
static final String MAX_ALLOC_KEY =
"hbase.hregion.memstore.mslab.max.allocation";
static final int MAX_ALLOC_DEFAULT = 256 * 1024; // allocs bigger than this
don't go through
// allocator
{code}
> 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.
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