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https://issues.apache.org/jira/browse/HBASE-5954?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13760865#comment-13760865
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Luke Lu commented on HBASE-5954:
--------------------------------

As you've found out, the fsync performance is very sensitive to the disk 
controller and its settings. You need a SATA/SAS controller (RAID or not) with 
battery or (recently) flash (FBWC in HP cards, nvcache in Dell cards) backed 
write cache to get good and safe sync performance on HDFS as the additional 
seek to sync the checksum file is really expensive without a write cache to 
queue the writes, which calls for HDFS-2699, which I think should be an per 
file option.
                
> Allow proper fsync support for HBase
> ------------------------------------
>
>                 Key: HBASE-5954
>                 URL: https://issues.apache.org/jira/browse/HBASE-5954
>             Project: HBase
>          Issue Type: Improvement
>            Reporter: Lars Hofhansl
>            Assignee: Lars Hofhansl
>            Priority: Critical
>             Fix For: 0.98.0
>
>         Attachments: 5954-trunk-hdfs-trunk.txt, 5954-trunk-hdfs-trunk-v2.txt, 
> 5954-trunk-hdfs-trunk-v3.txt, 5954-trunk-hdfs-trunk-v4.txt, 
> 5954-trunk-hdfs-trunk-v5.txt, 5954-trunk-hdfs-trunk-v6.txt, hbase-hdfs-744.txt
>
>
> At least get recommendation into 0.96 doc and some numbers running w/ this 
> hdfs feature enabled.

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