Hi!

> > > 	I'm hammering a Linux machine by placing a high volume
> > > (1,000,000 hits/day, 500,000 CGI hits/day) web site on it.  The box can
> > > certainly handle the traffic -- it's a dual Pentium II-400
      ~~~~~~~~~
> > > machine running

Are you so sure? 2x SMP on intel means about 30% performance increase,
if you are lucky. SMP on intel can even _slow you down_ for certain
kind of loads, and web server may be exactly this kind of load.

> > PS: If you are not able to sustain rate on UP, I do not think SMP will
> > help.
> 
> 	We have single processor machines we tried moving the site onto.
> These machines couldn't handle the load.  We watched as the load climbed
> to 80...  90...  And then I was distracted for a few minutes and someone
> told me the machine had crashed.  I wasn't surprised -- it couldn't handle
> it.

Try running UP kernel on that Pentium II-400 machine. If single cpu
can not handle the load, don't expect 2 cpu's to handle loads in
stable way.

BTW it is _web server_. Why don't you do congestion control? Don't try
to handle any new requests if load is above 20. That is probably the
right way. TCP stacks will retransmit their connection requests, and
things will slow down, but machine will stay alive.

									Pavel

-- 
I'm really pavel@ucw.cz. Look at http://195.113.31.123/~pavel.          Pavel
Hi! I'm a .signature virus! Copy me into your ~/.signature to help me spread!

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