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https://issues.apache.org/jira/browse/PHOENIX-3188?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15425601#comment-15425601
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Andrew Purtell commented on PHOENIX-3188:
-----------------------------------------

That sounds like a better approach than using protected member variables. 
Please let us know if you still need a blessed way to get a scanner ID. 

> Making renew leases of scanners more resilient
> ----------------------------------------------
>
>                 Key: PHOENIX-3188
>                 URL: https://issues.apache.org/jira/browse/PHOENIX-3188
>             Project: Phoenix
>          Issue Type: Improvement
>            Reporter: Samarth Jain
>         Attachments: PHOENIX-3188_hack.patch
>
>
> For renewing scanner leases, we need to perform an RPC per lease renewal. It 
> could happen that under load, these calls won't be picked up by region 
> handler threads soon enough which could cause queries to fail. There are a 
> couple of ways to solve this problem:
> 1) Issue renew lease calls at a higher priority. This essentially causes a 
> different thread pool to be used on the region servers. One such example is 
> the metadata and index updates calls we make. This would scale well unless 
> these special thread pools themselves get saturated with requests.
> 2) Batch up the the renewLease rpc calls. If HBase is able to provide us 
> scanner names and ids, then we can potentially renew leases for multiple 
> scanners by batching them up in one rpc. This would entail changes in both 
> client and server side of HBase. Client side - to expose scanner name. Server 
> side - to expose renewLease call on a scanner given a scanner name/id. 
> We still need to fix renewing leases for non-aggregate queries though. See 
> PHOENIX-1751



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