RE: [squid-users] Performance problems with 2.6.STABLE18

From: Mark Kent <mkent_at_messagelabs.com>
Date: Wed, 17 Dec 2008 21:57:49 -0000

Thanks, Kinkie.

The version that I'm running contains a couple of minor modifications,
so as a first pass I'd rather get the 2.6 version working, rather than
go through a repatch.

I tried running under valgrind, and it found a couple of leaks, but I'm
not sure that those are strictly the problem. If it were a "traditional"
memory leak, where memory was just wandering off, I don't quite see why
the CPU would climb along with the memory usage.

Mark.

-----Original Message-----
From: Kinkie [mailto:gkinkie_at_gmail.com]
Sent: Wednesday, December 17, 2008 4:50 PM
To: Mark Kent
Cc: squid-users_at_squid-cache.org
Subject: Re: [squid-users] Performance problems with 2.6.STABLE18

On Wed, Dec 17, 2008 at 4:24 PM, Mark Kent <mkent_at_messagelabs.com>
wrote:
>
> Hi,
>
> I'm currently having a performance issue with Squid 2.6.STABLE18
> (running on RHEL4). As I run traffic through the proxy, the memory
> grows steadily, and apparently without limit. This increase in memory
> usage is coupled with a steadily growing CPU usage, up to a point at
> which a single core is saturated (97% usage at ~400MB of RSS). At this

> point, the latency of requests increases. When the load is taken off
> the proxy, the CPU returns to minimal usage, but the memory usage
> sticks at the high water mark.

> I should point out that I'm using squid for authentication only (HTTP

> digest), not for caching. Consequently, I have maximum_object_size and

> maximum_object_size_in_memory both set to 0 in the squid config file.
> My understanding is that this should be sufficient to stop squid from
> caching.
>
> There's plenty of spare physical RAM on the machine, so it seems
> unlikely that it's a memory shortage causing the performance problem.
> My interpretation is that something has gotten too large for Squid to
> handle but, without object caching, it's not clear to me what that
> might be. I would blame the authentication cache, but there's only
> 2000 different users.
>
> Does anyone have an idea what might be going on, and how to fix it?

There may be a memory leak somewhere..
Squid 2.6 is rather old, can you try upgrading to the last 2.7 STABLE
release?

    Kinkie

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Received on Wed Dec 17 2008 - 21:58:01 MST

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