From: Jim Weirich <jim@...>
Date: 2004-05-11T05:39:49+09:00
Subject: Re: Roundup of new RubyGems features

(cross posted to Ruby Talk and Rake-devel)

Jim Weirich wrote:
> It is more likely that the cause of a slow rake startup is the time it 
> takes to calculate any filelists used for dependency detection.  For 
> example, the filelist used for the clean target searches your entire 
> project tree looking for files that can be deleted.  An obvious 
> optimization would be to delay the creation of a filelist until we 
> really need it.
> 
> If slow startups are a problem, I'll look into some possible fixes.


Several people have indicated to me that the startup is a minor problem. 
  The following URL is for a experimental gem for rake that using 
delayed filelists.

     http://onestepback.org/software/rake/download/rake-0.3.2.2.gem

     (NOTE: don't move this to a gem server until I get some feedback on 
it, thanks)

FileLists (array-like objects that contain file names) are normally 
built at the time they are declared.  This can be quite expensive.  For 
example:

    SOURCE_FILES = FileList['**/*.rb']

will search your entire project tree and find all the ruby source files 
and add them to the SOURCE_FILES file list.  If done at the top level of 
a rakefile (and most are), this list will be done on every invocation of 
rake (even if you say "rake --help").

In the experimental gem above, the building of the FileList is actually 
delayed until the first time the data is required.  If the file list is 
used in a dependency calculation, you probably won't see any difference. 
  If the file list is only used in the body of a task (such as the CLEAN 
list, which is a major offender), then this should speed things up a bit.

For those who have noticed slow starts, give this gem a try and let me 
know if it helps or if it causes other problems.

Thanks!

Some GEM Instructions:

If you have rake installed as a gem, just download the URL above and do 
a local gem installation (e.g.   gem -Li rake-0.3.3.2.gem) and you can 
start using it immediately.  If you wish to uninstall it, then just do a 
  "gem -U rake" and select the 0.3.3.2 version.  The previous gem 
version of rake should be reestablished.

If you are not using the gem version of rake, than grab the latest CVS 
and install it normally.

-- 
-- Jim Weirich    jim@weirichhouse.org     http://onestepback.org
-----------------------------------------------------------------
"Beware of bugs in the above code; I have only proved it correct,
not tried it." -- Donald Knuth (in a memo to Peter van Emde Boas)