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https://issues.apache.org/jira/browse/HBASE-29573?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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Charles Connell updated HBASE-29573:
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    Release Note: 
Each RegionServer now always caches the full contents of the hbase:quota table. 
If you have a very large quota table, this could cause excessive memory usage.

On each refresh, a RegionServer's quota cache will reset its quota usage 
tracking. This means that if a user was approaching their quota limit, that 
will be forgotten and they will get a empty quota limiter all over again. For 
quotas defined over long time intervals, this could be a meaningful difference. 
As a reminder, the default quota cache refresh interval is 12 hours.

> Fully load QuotaCache instead of reading individual rows on demand
> ------------------------------------------------------------------
>
>                 Key: HBASE-29573
>                 URL: https://issues.apache.org/jira/browse/HBASE-29573
>             Project: HBase
>          Issue Type: Improvement
>            Reporter: Charles Connell
>            Assignee: Charles Connell
>            Priority: Minor
>              Labels: pull-request-available
>
> I've found that HBASE-29479 will, in practice, increase load on the quota 
> table quite a bit. While it achieved its goal of quota correctness, this 
> increase in load is an unacceptable downside.
> In response, I'd like to find a way for QuotaCache to always serve correct 
> quotas, and also keep load on the quota table low. There is a simple way to 
> do this, which is to simply scan the entire table into memory at startup, 
> again when quotas change, plus every refresh interval. This also simplifies 
> the QuotaCache.



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