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https://issues.apache.org/jira/browse/CASSANDRA-4718?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13986060#comment-13986060
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Jason Brown commented on CASSANDRA-4718:
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bq. translates to around 60us/up

Did you mean 60us/*op* ? Also, are these just requests from (new) cassandra 
stress? You've described the time to process each 'tiny message' but not what a 
tiny message is :). How are you measuring the time for each request (more for 
my own curiosity)? 


> More-efficient ExecutorService for improved throughput
> ------------------------------------------------------
>
>                 Key: CASSANDRA-4718
>                 URL: https://issues.apache.org/jira/browse/CASSANDRA-4718
>             Project: Cassandra
>          Issue Type: Improvement
>            Reporter: Jonathan Ellis
>            Assignee: Jason Brown
>            Priority: Minor
>              Labels: performance
>             Fix For: 2.1.0
>
>         Attachments: 4718-v1.patch, PerThreadQueue.java, baq vs trunk.png, op 
> costs of various queues.ods, stress op rate with various queues.ods, 
> v1-stress.out
>
>
> Currently all our execution stages dequeue tasks one at a time.  This can 
> result in contention between producers and consumers (although we do our best 
> to minimize this by using LinkedBlockingQueue).
> One approach to mitigating this would be to make consumer threads do more 
> work in "bulk" instead of just one task per dequeue.  (Producer threads tend 
> to be single-task oriented by nature, so I don't see an equivalent 
> opportunity there.)
> BlockingQueue has a drainTo(collection, int) method that would be perfect for 
> this.  However, no ExecutorService in the jdk supports using drainTo, nor 
> could I google one.
> What I would like to do here is create just such a beast and wire it into (at 
> least) the write and read stages.  (Other possible candidates for such an 
> optimization, such as the CommitLog and OutboundTCPConnection, are not 
> ExecutorService-based and will need to be one-offs.)
> AbstractExecutorService may be useful.  The implementations of 
> ICommitLogExecutorService may also be useful. (Despite the name these are not 
> actual ExecutorServices, although they share the most important properties of 
> one.)



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