From: ara.t.howard@...
Date: 2006-03-18T00:47:54+09:00
Subject: Re: Writing long-running daemons without memory leaks?

On Sat, 18 Mar 2006, Toby DiPasquale wrote:

> Hi all,
>
> I am in the middle of writing some code that will exist as a
> long-running process on a number of machines. I am having trouble
> keeping memory utilization down, which is important in this case,
> because other processes on these machines will have priority to use the
> majority of RAM on these boxes for other tasks. The daemon itself is
> pretty simple, just reading and writing files and keeping some small
> state, but it also needs to cache large writes from multiple clients.
> When it does this, I find that this memory is not freed.
>
> My question is, I've heard from numerous accounts that WEBrick also
> leaks memory, and I would suspect that Mongrel does, too (though I
> haven't confirmed that) for the same reason. I understand that Ruby's GC
> is conservative, but can anyone point me to documentation, reference,
> source code, anything really that will help me better understand how to
> write Ruby code that doesn't "leak" and can be sustained as a
> long-running process without an ever-increasing memory footprint?
>
> Any help would be greatly appreciated. Thanks in advance.
>
> P.S. I've read the Pickaxe's lone page on the subject (in the Duck
> Typing chapter) and I've seen Why's article about the same
> (http://whytheluckystiff.net/articles/theFullyUpturnedBin.html).
>
> P.P.S. Has Minero Aoki's Ruby book been translated to English anywhere?
> I hear that it has a whole chapter on GC...

i'm running dozens of ruby daemons, some of which are extremely (months at a
time) long lived and have not seen any gc issues.  can you post a specific
(minimal) example that you find leaks memory?

regards.

-a
-- 
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