[
https://issues.apache.org/jira/browse/HBASE-10278?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13934926#comment-13934926
]
Jean-Marc Spaggiari commented on HBASE-10278:
---------------------------------------------
Is there any metrics to say "we have switched" that number of times, "we have
waiting an average of" before switching, in "total operation took x ms", and
"in total it will have taken x ms" (based on the duration of the first thread)?
Or we do not record that for now?
> Provide better write predictability
> -----------------------------------
>
> Key: HBASE-10278
> URL: https://issues.apache.org/jira/browse/HBASE-10278
> Project: HBase
> Issue Type: New Feature
> Reporter: Himanshu Vashishtha
> Assignee: Himanshu Vashishtha
> Attachments: 10278-wip-1.1.patch, Multiwaldesigndoc.pdf,
> SwitchWriterFlow.pptx
>
>
> Currently, HBase has one WAL per region server.
> Whenever there is any latency in the write pipeline (due to whatever reasons
> such as n/w blip, a node in the pipeline having a bad disk, etc), the overall
> write latency suffers.
> Jonathan Hsieh and I analyzed various approaches to tackle this issue. We
> also looked at HBASE-5699, which talks about adding concurrent multi WALs.
> Along with performance numbers, we also focussed on design simplicity,
> minimum impact on MTTR & Replication, and compatibility with 0.96 and 0.98.
> Considering all these parameters, we propose a new HLog implementation with
> WAL Switching functionality.
> Please find attached the design doc for the same. It introduces the WAL
> Switching feature, and experiments/results of a prototype implementation,
> showing the benefits of this feature.
> The second goal of this work is to serve as a building block for concurrent
> multiple WALs feature.
> Please review the doc.
--
This message was sent by Atlassian JIRA
(v6.2#6252)
