Re: [squid-users] H/W requirement for Squid to run in bigger scene like ISP

On mán, 2008-07-14 at 02:25 -0700, bijayant kumar wrote:
> In my observations since Squid is a single threaded(not a multithread)
> s/w, so there is no need to use dual/quad core processor, and RAM is
> also not very important factor because somewhere i read, "10MB RAM for
> every 1 GB of cache space on disk". So RAM is also ok. I will use 4-8
> GB RAM and it should be fine. I think i am going/thinking into right
> direction. Please suggest me, what should be the H/W requirement for
> the server where you can expect 1200-1500 concurrent connection to the
> squid at a time.

I am running Squid 2.5 and I believe this is outdated information.

The usage of cpus depends on the configuration. If You configure Squid
to use just ufs cache it will not make an alternate thread. But in my
configuration I use aufs cache and that makes an alternate thread or
process just to take care of the of the disk I/O. That is an advantage
if You have a dual processor machine.

Also with regard to RAM the 10MB RAM per 1 GB disk cache, it only holds
for 32 bit machines. I have calculated that for 64 bit machines, it is
14 MB per 1 GB disk cache. Maybe somebody would confirm this.

Then there are the usual tasks on the machine like managing logs and
doing the kernel tasks (swapping, IP-firewall, etc.), and on a heavily
loaded machine, You would probably not want a bottleneck in that area.

With todays hardware, wich is often dual processor by default, there are
very little savings using only one processor. Chances are that Your
users will hate the proxy server, if it turns out to be a bottleneck
during heavy load.

The challenge is the DISK I/O, the disk configuration and how You
tune the cache file system.

I would like to stress that I am not an expert on Squid, and I would
like some critique or opinions on the above.

-- 
Kindest Regards, Anna Jonna Ármannsdóttir,       %&   A: Because people read from top to bottom.
Unix System Aministration, Computing Services,   %&   Q: Why is top posting bad?
University of Iceland.