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https://issues.apache.org/jira/browse/DERBY-2911?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel#action_12523256
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Daniel John Debrunner commented on DERBY-2911:
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I'd say option 2 is best.

> Implement a buffer manager using java.util.concurrent classes
> -------------------------------------------------------------
>
>                 Key: DERBY-2911
>                 URL: https://issues.apache.org/jira/browse/DERBY-2911
>             Project: Derby
>          Issue Type: Improvement
>          Components: Performance, Services
>    Affects Versions: 10.4.0.0
>            Reporter: Knut Anders Hatlen
>            Assignee: Knut Anders Hatlen
>            Priority: Minor
>
> There are indications that the buffer manager is a bottleneck for some types 
> of multi-user load. For instance, Anders Morken wrote this in a comment on 
> DERBY-1704: "With a separate table and index for each thread (to remove latch 
> contention and lock waits from the equation) we (...) found that 
> org.apache.derby.impl.services.cache.Clock.find()/release() caused about 5 
> times more contention than the synchronization in LockSet.lockObject() and 
> LockSet.unlock(). That might be an indicator of where to apply the next push".
> It would be interesting to see the scalability and performance of a buffer 
> manager which exploits the concurrency utilities added in Java SE 5.

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