RE: [squid-users] Slow Squid

From: Sturgis, Grant <Grant.Sturgis@dont-contact.us>
Date: Tue, 16 Nov 2004 12:32:24 -0700

>
> On 15.11 12:23, Sturgis, Grant wrote:
> > I am writing for ideas on how I can increase the performance of my
> > squid cache.
> >
> > I am running:
> >
> > cache_dir aufs on ext2
> [...]
>
> > The hardware is:
> >
> > Dell PE 1650
> > 2-Intel PIII 1133 MHz
> > 4 GB RAM
> >
> > The symptom is that during our peak utilization periods, when HTTP
> > requests get over about 750/min, the response time gets very slow,
> > over 800 ms or so. I understand that squid is single
> threaded, but we
> > are running a number of the redirector processes and it
> seems that the
> > CPU workload is distributed fairly well. This is determined by
> > examining /proc/stat with MRTG. Neither CPU seems to reach
> above 55%
> > utilization so I do not think the system is CPU bound.
>
> 55% is already quite much, however that is probably not the problem.
>
>
> > One thing that is concerning:
> >
> > [root@proxy squid]# free -m
> > total used free shared buffers
> > cached
> > Mem: 3778 3756 22 0 472
> > 2154
> > -/+ buffers/cache: 1129 2649
> ^^^^
> this says you only use a bit more than 1GB of memory.

Another shot from today:

[root@proxy01bldr root]# free -m
             total used free shared buffers
cached
Mem: 3778 3758 20 0 497
2194
-/+ buffers/cache: 1065 2713
Swap: 8997 807 8190

Doesn't this say 807 MB of swap being used? Certainly that cannot be
good.

>
> > Also, I do understand that reiserfs is a recommended file
> system over
> > ext2; do you think it will make a large difference to change this?
>
> yes, there is high probability that changing to
> xfs/jfs/reiserfs would help you.
>
> > Any suggestions for things I can do to determine why my
> cache is slow
> > or how to make improvements in performance?
>
> try to see how disks are loaded using 'iostat -d 1'

I don't have that command, but I will load that package (sar I believe)
this afternoon.

>

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Received on Tue Nov 16 2004 - 12:31:44 MST

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