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https://issues.apache.org/jira/browse/HBASE-16438?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15942903#comment-15942903
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Anoop Sam John commented on HBASE-16438:
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I dont think Soft ref can be used. Once the CSLM is converted to CellChunkMap,
we dont have any hard refs to Chunks from any where (Cells are gone). Now the
ChunkMap contain chunkId and offset , length info. Now assume a GC picked and
removed these chunks (Ya there are no hard refs to it), and after a read comes
and we want to read back that Cell, what to do? !!!!
Ok if u also think CellChunkMap should be better used by off heap usage, can we
say CellChunkMap to be used along with off heap MSLAB pool usage only? In case
of off heap MSLAB all chunks will get pooled. There wont be any on demand chunk
creation. So we will keep this id vs chunk info in map iff CellChunkMap is in
place and so off heap MSLAB pool in place?
Any way the above mentioned use case ideally should not use MSLAB pool at all.
> 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
> Attachments: HBASE-16438_1.patch,
> HBASE-16438_3_ChunkCreatorwrappingChunkPool.patch,
> HBASE-16438_4_ChunkCreatorwrappingChunkPool.patch, HBASE-16438.patch,
> MemstoreChunkCell_memstoreChunkCreator_oldversion.patch,
> MemstoreChunkCell_trunk.patch
>
>
> 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.
> Why we need to embed the chunkid in the Cell is described by [~anastas] in
> this remark over in parent issue
> https://issues.apache.org/jira/browse/HBASE-14921?focusedCommentId=15244119&page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel#comment-15244119
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