lucene-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Yonik Seeley (JIRA)" <j...@apache.org>
Subject [jira] Commented: (LUCENE-753) Use NIO positional read to avoid synchronization in FSIndexInput
Date Thu, 21 Dec 2006 15:35:22 GMT
    [ http://issues.apache.org/jira/browse/LUCENE-753?page=comments#action_12460289 ] 
            
Yonik Seeley commented on LUCENE-753:
-------------------------------------

> The Javadoc says that transferTo can be more efficient because the OS can transfer bytes
> directly from the filesystem cache to the target channel without actually copying them.

Unfortunately, only for DirectByteBuffers and other FileChannels, not for HeapByteBuffers.
Sounds like we just need to do some benchmarking, but I have a bad feeling that all the checking
overhead Sun added to NIO will cause it to be slower in the single threaded case.


> Use NIO positional read to avoid synchronization in FSIndexInput
> ----------------------------------------------------------------
>
>                 Key: LUCENE-753
>                 URL: http://issues.apache.org/jira/browse/LUCENE-753
>             Project: Lucene - Java
>          Issue Type: New Feature
>          Components: Store
>            Reporter: Yonik Seeley
>         Attachments: FSIndexInput.patch, FSIndexInput.patch
>
>
> As suggested by Doug, we could use NIO pread to avoid synchronization on the underlying
file.
> This could mitigate any MT performance drop caused by reducing the number of files in
the index format.

-- 
This message is automatically generated by JIRA.
-
If you think it was sent incorrectly contact one of the administrators: http://issues.apache.org/jira/secure/Administrators.jspa
-
For more information on JIRA, see: http://www.atlassian.com/software/jira

        

---------------------------------------------------------------------
To unsubscribe, e-mail: java-dev-unsubscribe@lucene.apache.org
For additional commands, e-mail: java-dev-help@lucene.apache.org


Mime
View raw message