From: Robert Klemme <shortcutter@...>
Date: 2012-04-05T21:14:50+09:00
Subject: Re: Not a Memory Leak but Stale Objects - clears with GC.start

On Thu, Apr 5, 2012 at 1:06 PM, Tom Moulton <lists@ruby-forum.com> wrote:
> I have a long running process.
>
> When it gets busy the memory the task uses grows from
> 300-400MB to  1.2-1.8GB
>
> So I thought I had a leak... but when I do a GC.start
> (Garbage Collection start)
> the memory usage (shown by 'top') drops back to normal.
>
> As a temporary solution I have the GC.start run once a minute and then
> I started thinking...
>
> I see a lot of threads pointing out problems with Ruby memory management
> and garbage collection, so might this solution be ok to continue to use?

Many of those threads here which deal with GC are caused by
misunderstanding of GC.  I don't see that Ruby's GC has serious
problems in recent versions of Ruby.

> There is only one main loop, the rest are periodic calls
> to Proc objects.

Closures holding on to objects for longer than necessary?

> I thought when a function returns any stale objects could be released.
> (And in fact they are when I call GC.start, so something else is
> causing GC not to start on it's own)

I faintly remember that there once GC did not free all objects it
could free but don't remember the details - not even the Ruby version.

> I am running Debian linux and have
>
> ruby 1.8.7 (2010-08-16 patchlevel 302) [i486-linux]
>
> I know there are newer versions of ruby,
> but don't want to upgrade just yet...
>
> just lazy I guess :)

Yeah, you're lazy.  Bad boy! :-)

I'd go to 1.9.3 rather sooner than later because it's also faster for
many applications and it has Oniguruma which I wouldn't want to miss
any more.

Kind regards

robert


-- 
remember.guy do |as, often| as.you_can - without end
http://blog.rubybestpractices.com/