Re: Slow responses

On Mon, 26 Jan 1998, Dancer wrote:

> We're going to be running squid up to some extremely high loads in the near f$
> (50 requests per second and higher). I'm looking on some data to pinpoint the$
> of activity levels where we should shift our monitoring services to paranoid
> data-gathering, so we can get good pictures of what squid is doing if it shou$
> start to fold up under the load.
>
> Who runs at that level of requests per second (peak)? Who runs higher than th$
> What's the highest peak request rate anyone is running?

Our peak was 120 UDP / 335 TCP per sec (enough for this exclusive circle ?
:-)).
We're also sometimes seeing the mentioned behaviour. After a restart,
everything is fine for some hours. It happens only during evening
hours which is not peak *squid* usage time but peak *line* usage time, so
I suspect it's somehow related to that (packet losses, retransmits, tcp
buffers,
whatever).
This is with Arjan's inofficial patch to make more efficient use of the
UN*X filesystem cache running on Solaris 2.6.

>
> D

Markus

> > > horrible. Pages that can be fetced directly from the webserver
> > > may take a minute or two from the cache. There is no paging going on, and
> > > neither raw disk I/O nor network I/O seems to be a problem. Of my 16 dnss$
> > > processes the last few are rarely used. CPU load rarely goes above 0.5.
> > >
> > > The only oddity I find is this line in cache.log, appearing every few sec$
> > > while the cache is busy.:
> > >
> > > 98/01/22 23:09:52| diskHandleWrite: FD 23: disk write error: (32) Broken $
> > >
> > > Is this related? Any idea what might be the problem?
> >
> > We have the same problem here, running 1.1.20 on a HP/UX 10.20 machine.
> > At times of high load even TCP_HITs take up to 50 seconds (at least the
> > logfile says so) to be delivered to the clients. Request peak at our
> > site is about 20 requests per second and usually the machine has a load
> > of 0.7 or so. Maybe it is a general problem of squid with heavy load.
> >
> > Rainer
> >