[ 
https://issues.apache.org/jira/browse/CASSANDRA-4718?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13682777#comment-13682777
 ] 

Pavel Yaskevich commented on CASSANDRA-4718:
--------------------------------------------

I think even though we aren't in the most cache friendly behavior with variable 
size RMs we can still utilize better dispatch behavior with low cost 
synchronization. We can't do anything about blocking I/O operations requiring 
separate thread but I think it's time to re-evaluate NIO async sockets vs. 
having thread per in/out connection.
                
> 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
>            Priority: Minor
>         Attachments: baq vs trunk.png, PerThreadQueue.java
>
>
> 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.)

--
This message is automatically generated by JIRA.
If you think it was sent incorrectly, please contact your JIRA administrators
For more information on JIRA, see: http://www.atlassian.com/software/jira

Reply via email to