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https://issues.apache.org/jira/browse/HBASE-18715?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16146483#comment-16146483
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Duo Zhang commented on HBASE-18715:
-----------------------------------

Though the patch seems not very large but I think this is a big feature(also a 
great feature), so mind uploading a detailed design doc first?

And I think we can do this in several stages?

Thanks.

> isolate large query
> -------------------
>
>                 Key: HBASE-18715
>                 URL: https://issues.apache.org/jira/browse/HBASE-18715
>             Project: HBase
>          Issue Type: New Feature
>            Reporter: chenxu
>            Assignee: chenxu
>         Attachments: HBASE-18715-master-v1.patch, isolate result.png
>
>
> large queries are very expensive than the general operation, and often delay 
> insensitive.
> if not isolate, Handlers may be all used by the large query,
> lead to _Put_ or _Get_ slowly, so there need be an mechanism to isolate the 
> large query.
> for example we can use a separate _RpcExecutor_ to handle this.
> for the following type of queries we can think it is a large query:
> (1) _Scan_ has no startkey or endkey
> (2) Client call _ResultScanner.next()_ more than a certain threshold
> (3) Client call custom coprocessor which involves large queries(such as 
> _AggregateService_)
> for large queries, RegionServer should meet the following requirements
> (1) dynamic configure if isolate large query is turn on
> (2) setup certain Handlers to deal with large queries only
> (3) in offpeak hours, large queries are not isolate
> (4) dynamic configure if cache Blocks is turn on if the query is a large query



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