Re: [squid-users] access to cache is very high

thanks for the advice Amos
but I've just reset all objects in my cache (thus it's empty now)
and the CPU utilization has decreased dramatically (up to 17%),
but clients still get (rarely) error that the proxy is refusing connection.

2009/03/22 13:34:42| httpAccept: FD 8: accept failure: (53) Software caused connection abort
2009/03/22 15:16:49| httpAccept: FD 8: accept failure: (53) Software caused connection abort

I'll try your advice in my testlab first before go into live server.

thanks in advance.

--- On Fri, 3/20/09, Amos Jeffries <squid3_at_treenet.co.nz> wrote:

> From: Amos Jeffries <squid3_at_treenet.co.nz>
> Subject: Re: [squid-users] access to cache is very high
> To: "nyoman karna" <balique8061_at_yahoo.com>
> Cc: squid-users_at_squid-cache.org
> Date: Friday, March 20, 2009, 10:19 PM
> nyoman karna wrote:
> > guys,
> >
> > I've been using squid for 5 years in my educational
> institution
> > (IM Telkom - Telkom Institute of Management)
> > but this is the first time i encounter this problem.
> > need your expertise.
> >
> > I'm using HP Proliant ML110 G5 with 320GB of SATA
> disk.
> >
> > I'm using squid 2.6 stable 16 (FreeBSD 6.3) with 100GB
> of squid-cache.
> > when the cache was not yet full, there's no problem
> whatsoever
> > but when the cache is full (but still 90% of the
> mountpoint),
> > squid is always busy validating its objects
> > and refusing all client connection.
> >
> > this is part of file /usr/local/etc/squid/squid.conf
> > ------------------------------------------------
> > maximum_object_size 16384 KB
> > minimum_object_size 0 KB
> > maximum_object_size_in_memory 8 KB
> > cache_replacement_policy lru
> > memory_replacement_policy lru
> > cache_dir ufs /webcache 100000 64 256
> >
> > this is the capture when the squid refusing
> connection
> > -------------- (using top)
> ----------------------------------
> > CPU states: 39.5% user, 0.0% nice, 55.3% system, 5.3%
> interrupt, 0.0% idle
> >   PID USERNAME THR PRI NICE SIZE 
> RES STATE TIME  WCPU  COMMAND
> > 77059 squid     1  123 
>   0 186M 184M  RUN  0:10 86.26% squid
> >
> > -------------- (using systat)
> ----------------------------------
> >       /0%   
> /10    /20    /30    /40 
>   /50    /60    /70
> > ad4 MB/sXXXXX
> >   
> tps|XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
> >
> > -------------- (cache.log)
> ----------------------------------
> > 2009/03/20 09:54:44| httpAccept: FD 11: accept
> failure: (53) Software caused connection abort
> >
> >
>
> UFS as the slowest IO process in Squid, is not the best for
> large caches. Since you are on FreeBSD try diskd instead. No
> change of cache is needed to alter ufs->diskd as the
> storage manager type.
>
> Average HTTP object size these days is between 64KB and 128
> KB. Your max in-memory size of 8KB is causing a lot of
> objects to be disk-saved without need.
>
> Also check the garbage collection range you have set:
> http://www.squid-cache.org/Doc/config/cache_swap_low/
> http://www.squid-cache.org/Doc/config/cache_swap_high/
>
>
> Amos
> -- Please be using
>   Current Stable Squid 2.7.STABLE6 or 3.0.STABLE13
>   Current Beta Squid 3.1.0.6
>
Received on Sun Mar 22 2009 - 09:09:21 MDT