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https://issues.apache.org/jira/browse/HBASE-18128?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16036835#comment-16036835
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Anoop Sam John commented on HBASE-18128:
----------------------------------------

Agree to the point of replay with out considering the seqId (vs Last flushed 
seqId).  
I mean one WALEdit entry can have more than one cell in it.  So any chance of 
this kind of a meta cell is clubbed together with some other non meta cells 
within one WALEdit.  Here by the patch, we make it that none of the Cells in 
this WALEdit will be honoring the seqId then.. But I think there is no 
possibility of this clubbing.. Just asked so that u can have a look. U clear 
now?

> compaction marker could be skipped 
> -----------------------------------
>
>                 Key: HBASE-18128
>                 URL: https://issues.apache.org/jira/browse/HBASE-18128
>             Project: HBase
>          Issue Type: Improvement
>          Components: Compaction, regionserver
>            Reporter: Jingyun Tian
>            Assignee: Jingyun Tian
>         Attachments: HBASE-18128.patch
>
>
> The sequence for a compaction are as follows:
> 1. Compaction writes new files under region/.tmp directory (compaction output)
> 2. Compaction atomically moves the temporary file under region directory
> 3. Compaction appends a WAL edit containing the compaction input and output 
> files. Forces sync on WAL.
> 4. Compaction deletes the input files from the region directory.
> But if a flush happened between 3 and 4, then the regionserver crushed. The 
> compaction marker will be skipped when splitting log because the sequence id 
> of compaction marker is smaller than lastFlushedSequenceId.
> {code}
>         if (lastFlushedSequenceId >= entry.getKey().getLogSeqNum()) {
>           editsSkipped++;
>           continue;
>         }
> {code}



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