[ 
https://issues.apache.org/jira/browse/MAPREDUCE-1114?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12786225#action_12786225
 ] 

Doug Cutting commented on MAPREDUCE-1114:
-----------------------------------------

> I look at this as a 60% speedup in my development cycle rather than a few % 
> speedup in the full build.

I agree with this logic.  My most common development cycle is to run a single 
unit test.  For Avro this takes just a few seconds, and I'm willing to wait 
without finding a new task to work on.  With Hadoop this takes long enough that 
I switch to doing something else, lose my context, etc.  Improving this 
significantly will significantly improve many developers productivity.

I wonder if we can simply check if build/ivy/lib/Hadoop-Hdfs/{common,test} 
exist, and, if they do, assumes they're up-to-date, and only runs Ivy 
otherwise.  Might that be simpler?


> Speed up ivy resolution in builds with clever caching
> -----------------------------------------------------
>
>                 Key: MAPREDUCE-1114
>                 URL: https://issues.apache.org/jira/browse/MAPREDUCE-1114
>             Project: Hadoop Map/Reduce
>          Issue Type: Improvement
>          Components: build
>    Affects Versions: 0.22.0
>            Reporter: Todd Lipcon
>            Assignee: Todd Lipcon
>            Priority: Minor
>         Attachments: mapreduce-1114.txt, mapreduce-1114.txt, 
> mapreduce-1114.txt
>
>
> An awful lot of time is spent in the ivy:resolve parts of the build, even 
> when all of the dependencies have been fetched and cached. Profiling showed 
> this was in XML parsing. I have a sort-of-ugly hack which speeds up 
> incremental compiles (and more importantly "ant test") significantly using 
> some ant macros to cache the resolved classpaths.

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

Reply via email to