[ 
https://issues.apache.org/jira/browse/MAPREDUCE-1114?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12786265#action_12786265
 ] 

Chris Douglas commented on MAPREDUCE-1114:
------------------------------------------

bq. Comparing the 15 second payoff to the full build time isn't particular 
important to me. For me, the ability to quickly iterate on code while 
recompiling and rerunning unit tests is the big payoff

As a vi user, I got that. I haven't argued that the long build times are 
unimportant, but that a hack introducing a custom caching layer for classpaths 
is not, in my mind, a justifiable tradeoff in complexity. Maintaining black 
magic in the build is tedious and avoidable.

bq. the slowness is actually in the resolve task which generates the various 
classpath properties in ant

Aren't the classpaths named? Would there be a way to short-circuit the 
resolution if it created/checked for a file mapped to that path?

bq. 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.

As a workaround: depending on how often I'm running it, adding a {{main}} to 
the unit test is sometimes worthwhile.

> 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