[Mongrel] leaking weirdness

Luis Lavena luislavena at gmail.com
Mon Apr 28 16:24:50 EDT 2008

On Mon, Apr 28, 2008 at 5:14 PM, Roger Pack <lists at ruby-forum.com> wrote:
> Previously posted on ruby talk.  Response...silence :)

Didn't saw that post, sorry.

>  ......
>  Perhaps someone out there can help give me a clue about the following
>  situation:
>  My mongrel processes seemed to be leaking.
>  As an example of this, if I added this code to the bottom of
>  environment.rb
>  Thread.new {loop do; print 'w'; end}
>  it didn't affect memory.  At first.  However after the web server got
>  its
>  first hit its memory consumption would sky-rocket.  [i.e. it would
>  monotonically grow by about 50MB/s]
>  Then I ran the same scenario using webrick, instead of mongrel [1.1.3].
>  No leak.
>  Then I'm thinking 'hmm maybe it's mongrel and the mongrel guys have
>  fixed this.'
>  Update my gem to 1.1.4 from 1.1.3.
>  Using mongrel this time.
>  No leak! Yea!
>  Now this is the weird part.
>  Attempted to recreate the bug.
>  Uninstalled mongrel 1.1.4, reinstalled 1.1.3
>  uninstalled daemons [its dependency] 1.0.10, reinstalled 1.0.9 [what I
>  had before].
>  Ran it with Mongrel again [which is where it used to leak].
>  No leak.
>  I am so confused!
>  Perhaps rubygems was updated and so it "compiled it right this time"?
>  Note that there don't appear to be significant code changes in mongrel
>  from 1.1.3 to 1.1.4, though there could be, I'm not sure.  It's probably
>  not even a mongrel problem.
>  Maybe if somebody else who 'suspects' a memory leak could try my code
>  and see if it leaks theirs, that would be well appreciated.
>  The good news is that "maybe" updating rubygems and recompiling mongrel
>  helps with memory leaks in rails apps.
>  Thoughts?
>  -R
>  OS X PPC patchlevel 111

Did you upgraded rubygems at the time you updated mongrel from 1.1.3 to 1.1.4?

Also, did you hit the same request/url during testing and recreating
this bug? (just to be sure).

I've seen lot of complains about "my mongrel is eating my memory", but
as Erza commented in his Rack Rails [1], it seems lot of stuff at
Rails needs attention and lot of fixes, since they eat memory like a
hungry baby... and is not directly fault of Mongrel.

Could be Ruby, rubygems, some plugin you're using, even Rails :-P

If you cannot revert back to the version of rubygems you was using to
test the exact same environment, there is nothing more we can do
except: thank god you got that solved! :-P

Maybe you can see bleakhouse [2] and give it a whirl?

[1] http://brainspl.at/articles/2008/04/25/hey-rails-nice-rack
[2] http://blog.evanweaver.com/articles/2008/04/06/bleakhouse-4/
Luis Lavena
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