RE: [squid-users] High Utilization

> -----Original Message-----
> From: Jorgen Rosink [mailto:jrosink@gmail.com]
> Sent: Thursday, March 17, 2005 7:31 AM
> To: squid-users@squid-cache.org
> Subject: [squid-users] High Utilization
>
>
> Hi,
>
> I'm using 2.5.STABLE8 from Debian Sarge and experiencing very high
> utilization and random stalls client side at peek time. Did upgrade to
> 2.5.STABLE9 from Debian Unstable, but no difference so far. I'm almost
> sure I misconfigured some (or all ;-)) things, but totally out of
> options.
>
> To see some performance:
>
> http://rosink.op.het.net/squid/day_stats.png
>

You are seeing peaks of over 20 Mb/sec traffic, from 2500 clients. That's
quite a bit for one box to be handling. What kind of requests per second
does that translate out to? (Cache Utilization in the cache manager will
divulge this information). You might just be hitting the limits of one
squid server.

> http://rosink.op.het.net/squid/week_stats.png
>
> http://rosink.op.het.net/squid/info.txt
>

Requests seem to be serviced in a timely manner. Even misses are taking
just 1/10th of a second to complete.

> Box is a Xeon 2.4Ghz with 1GB ram and three dedicated 9GB SCSI cache

Info.txt shows pretty low hit ratios, so perhaps you could use more disk
space, and Squid can easily use more than a GB of RAM (especially if you
have lots of disk cache).

> volumes. Connections are coming from several (50 max) child proxies,
> mostly BorderManager and ISA, used by about 2500 workstations. I'm
> using the following configuration:
>
> http://rosink.op.het.net/squid/squid.conf
>

From what I've read, you probably don't want to set the cache_dir to take up
all of the formatted space on the drive. Aside from that, you might want to
change your DO_NOT_CACHE acls to include a period in from of the domain
(i.e. acl DO_NOT_CACHE dstdomain .zadkinezorg.nl) so it matches subdomains.
For clarity you might put all of the child proxy ips in a commented text
file, and just reference that file with a single acl, and a single
http_access allow statement. You might want to turn buffered_logs on
(though the Squid Conf Manual says that it's not likely going to be much of
a problem). You are creating cache digests, but are any of the child
proxies using it? Are any of the child proxies capable of bypassing this
Squid server (if not, I'm not sure of the utility of advertising what this
cache holds).

> I'm aware of the extreme number of squidguard redirectors (32), but
> that's the only way to make the log messages about blocking
> redirectors disappear.
>
> Could anyone see what's happening ?
>
> Thanks,
>
> Jorgen Rosink
Received on Thu Mar 17 2005 - 16:00:10 MST