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https://issues.apache.org/jira/browse/PHOENIX-5069?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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Bin Shi updated PHOENIX-5069:
-----------------------------
    Description: 
The current Phoenix Stats Cache uses TTL based eviction policy. A cached entry 
will expire after a given amount of time (900s by default) passed since the 
entry's been created. This will lead to cache miss when Compiler/Optimizer 
fetches stats from cache at the next time. As you can see from the above graph, 
fetching stats from the cache is a blocking operation — when there is cache 
miss, it has a round trip over the wire to scan the SYSTEM.STATS Table and to 
get the latest stats info, rebuild the cache and finally return the stats to 
the Compiler/Optimizer. Whenever there is a cache miss, this blocking call 
causes significant performance penalty and see periodic spikes.

*This Jira suggests to use asynchronous refresh mechanism to provide a 
non-blocking cache. For details, please see the linked design document below.*

[~karanmehta93] [[email protected]] [~dbwong] [~elserj] [[email protected]] 
[~sergey soldatov] 

  was:
The current Phoenix Stats Cache uses TTL based eviction policy. A cached entry 
will expire after a given amount of time (900s by default) passed since the 
entry's been created. This will lead to cache miss when Compiler/Optimizer 
fetches stats from cache at the next time. As you can see from the above graph, 
fetching stats from the cache is a blocking operation — when there is cache 
miss, it has a round trip over the wire to scan the SYSTEM.STATS Table and to 
get the latest stats info, rebuild the cache and finally return the stats to 
the Compiler/Optimizer. Whenever there is a cache miss, this blocking call 
causes significant performance penalty and see periodic spikes.

This Jira suggests to use asynchronous refresh mechanism to provide a 
non-blocking cache. 


> Use asynchronous refresh to provide non-blocking Phoenix Stats Client Cache
> ---------------------------------------------------------------------------
>
>                 Key: PHOENIX-5069
>                 URL: https://issues.apache.org/jira/browse/PHOENIX-5069
>             Project: Phoenix
>          Issue Type: Improvement
>            Reporter: Bin Shi
>            Priority: Major
>
> The current Phoenix Stats Cache uses TTL based eviction policy. A cached 
> entry will expire after a given amount of time (900s by default) passed since 
> the entry's been created. This will lead to cache miss when 
> Compiler/Optimizer fetches stats from cache at the next time. As you can see 
> from the above graph, fetching stats from the cache is a blocking operation — 
> when there is cache miss, it has a round trip over the wire to scan the 
> SYSTEM.STATS Table and to get the latest stats info, rebuild the cache and 
> finally return the stats to the Compiler/Optimizer. Whenever there is a cache 
> miss, this blocking call causes significant performance penalty and see 
> periodic spikes.
> *This Jira suggests to use asynchronous refresh mechanism to provide a 
> non-blocking cache. For details, please see the linked design document below.*
> [~karanmehta93] [[email protected]] [~dbwong] [~elserj] [[email protected]] 
> [~sergey soldatov] 



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