lucene-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Raghu Angadi (JIRA)" <j...@apache.org>
Subject [jira] Commented: (LUCENE-1121) Use nio.transferTo when copying large blocks of bytes
Date Fri, 04 Apr 2008 18:15:24 GMT

    [ https://issues.apache.org/jira/browse/LUCENE-1121?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12585677#action_12585677
] 

Raghu Angadi commented on LUCENE-1121:
--------------------------------------

Only savings I would expect from transferTo() would be CPU reduction. Does the benchmark above
measure wall clock time or "cpu time"? Btw, the windows results are pretty... strange.

HADOOP-3164 shows expected CPU benefit. Still need to do more extensive tests where I max
out CPU with and without patch and compare the wall clock time. Initial test just compares
cpu reported on /proc/pid/stat with a test that is disk bound.

> Use nio.transferTo when copying large blocks of bytes
> -----------------------------------------------------
>
>                 Key: LUCENE-1121
>                 URL: https://issues.apache.org/jira/browse/LUCENE-1121
>             Project: Lucene - Java
>          Issue Type: Improvement
>          Components: Store
>            Reporter: Michael McCandless
>            Assignee: Michael McCandless
>            Priority: Minor
>         Attachments: LUCENE-1121.patch, LUCENE-1121.patch, testIO.java
>
>
> When building a CFS file, and also when merging stored fields (and
> term vectors, with LUCENE-1120), we copy large blocks of bytes at
> once.
> We currently do this with an intermediate buffer.
> But, nio.transferTo should be somewhat faster on OS's that offer low
> level IO APIs for moving blocks of bytes between files.

-- 
This message is automatically generated by JIRA.
-
You can reply to this email to add a comment to the issue online.


---------------------------------------------------------------------
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