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

2008/12/17 Mark Kent <mkent_at_messagelabs.com>:

> 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.

Grab oprofile and do some digging?

Adrian

>
> 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 - 22:42:02 MST