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https://issues.apache.org/jira/browse/HBASE-8338?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13645813#comment-13645813
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Nicolas Liochon commented on HBASE-8338:
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Agreed, but it can't be done without the client application: it was writing 
something and writing this something can't be done as the region is not there. 
For example, we have a callback during the put process. We call this callback 
only on success. We could call it on failure, and let the user decides:
- ignore
- stop (today's behavior)
- replace.

basically the callback would return a boolean to let the process continue or 
not.

It's quite easy to do, if that's what we want...
                
> Latency Resilience; umbrella list of issues that will help us ride over bad 
> disk, bad region, ec2, etc.
> -------------------------------------------------------------------------------------------------------
>
>                 Key: HBASE-8338
>                 URL: https://issues.apache.org/jira/browse/HBASE-8338
>             Project: HBase
>          Issue Type: Umbrella
>          Components: LatencyResilience
>            Reporter: stack
>            Priority: Critical
>
> Chatting w/ Elliott, we started listing out items to fix that would help keep 
> hbase latency approximately constant as disks went bad, were saturated by a 
> neighbour (ec2), etc.
> I must made a new LatencyResilience issue category to tag issues that 
> contribute to this project.
> I have to go at moment but when I get back I'll start to link in existing 
> issues that help this project along and I'll file new ones.
> Here is what we chatted about:
> + Multiple WALs effort will help keep write latency roughly constant.
> + Figuring how to get a new read started over dfsclient if current replica 
> read is taking too long would help keep reads about constant (maybe could 
> exploit the nkeywal hackery messing w/ replicas order).
> + There is an issue where client can currently pile up on a single region 
> because of the way we do client queues by regionserver.  This needs fixing.
> The above are few ideas worth further exploration at least.
> Idea is to try and bring down our 95percentiles and to make us more robust in 
> the face of dying disks, etc.  I see this issue rising to the fore now there 
> has been good progress on the MTTR project.

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