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https://issues.apache.org/jira/browse/HBASE-18128?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16036458#comment-16036458
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Jingyun Tian commented on HBASE-18128:
--------------------------------------

[~anoop.hbase] Thanks for comment, I think solve this in a generic way is a 
good idea, I will update the patch this work.
Only compaction marker need this treatment right now. Because when you replay a 
recovered edit, server will check if it is compaction marker, if it is, server 
will delete the old files before opening region. Currently there are no other 
meta cells have special treatment.



> 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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