Re: [squid-users] performance: max. # of parallel users

On Wed, Jun 06, 2001 at 01:44:22PM +0200, Winfried Fromm wrote:
> I have a performance related question.
> If I build a *transparent* squid proxy with *no* cache enabled(!) -> how many
> parallel users with "normal surfing behaviour" will be able to use that proxy
> without tearing the performance down to much? (roughly estimated!)
>
> The Configuration:
>
> - Sun Netra T1
> - 1 x 440 MHz CPU
> - 512 MB RAM
> - 100 MBit uplink
> - OS: Sun Solaris 7
> - Squid 2.4 transparent, no cache
>
> How many real users will be able to use this machine, presuming that they
> will behave as a normal surfer (downloding a page - reading for a few
> seconds - downloading the next page - reading - downloading a bigger file
> .....)
 
We currently have a couple of cacheless proxy servers acting as "overflow"
machines in our proxy farm (behind a L4 switch), although they are shortly
to be replaced. These are Sun Ultra 10s, 440MHz, 512MB RAM, Solaris 8.
I find in our situation that performance suffers noticeably beyond 60
requests per second, and cannot be pushed much beyond 80.

This is slightly better than we can do if we use cache disks on similar
machines (my suspicion is that we are let down by disk performance). I've
found a test PC (admittedly with rather faster processor) to be capable of
almost double the throughput in cacheless mode.

"Number of users" depends considerably on usage patterns - yours may well
be very different to those of a large university such as ourselves.

> I think the performance will probably be restricted just by the uplink
> bandwith, but I never really tried it...

This is clearly not the case in my experience - filling a 100Mbit uplink
would generally require many hundreds of requests per second.

        Robin

-- 
--------------- Robin Stevens  <robin.stevens@oucs.ox.ac.uk> -----------------
Oxford University Computing Services ----------- Web: http://www.cynic.org.uk/
------- (+44)(0)1865: 273212 (work) 273275 (fax)  Mobile: 07776 235326 -------