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https://issues.apache.org/jira/browse/CASSANDRA-7438?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14228515#comment-14228515
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Ariel Weisberg commented on CASSANDRA-7438:
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+1 To what Benedict suggests.

One minor nit. Resize pauses will happen across stripes at almost exactly the 
same time. I know with say 12 stripes it's very bad. With more than that it 
might start to spread them out, but I haven't seen that in action.

We can iterate on resize pause issues later if necessary. It's a warmup issue 
which will be a problem for some, but might not cripple the feature.

> Serializing Row cache alternative (Fully off heap)
> --------------------------------------------------
>
>                 Key: CASSANDRA-7438
>                 URL: https://issues.apache.org/jira/browse/CASSANDRA-7438
>             Project: Cassandra
>          Issue Type: Improvement
>          Components: Core
>         Environment: Linux
>            Reporter: Vijay
>            Assignee: Vijay
>              Labels: performance
>             Fix For: 3.0
>
>         Attachments: 0001-CASSANDRA-7438.patch, tests.zip
>
>
> Currently SerializingCache is partially off heap, keys are still stored in 
> JVM heap as BB, 
> * There is a higher GC costs for a reasonably big cache.
> * Some users have used the row cache efficiently in production for better 
> results, but this requires careful tunning.
> * Overhead in Memory for the cache entries are relatively high.
> So the proposal for this ticket is to move the LRU cache logic completely off 
> heap and use JNI to interact with cache. We might want to ensure that the new 
> implementation match the existing API's (ICache), and the implementation 
> needs to have safe memory access, low overhead in memory and less memcpy's 
> (As much as possible).
> We might also want to make this cache configurable.



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