[lkml]   [2001]   [Nov]   [4]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
SubjectRe: [khttpd-users] khttpd vs tux
On Sun, 4 Nov 2001, Erik Mouw wrote:

> On Sat, Nov 03, 2001 at 08:18:19PM +0100, Roy Sigurd Karlsbakk wrote:
> > > Each GigE card will need its own 66MHz PCI bus. Each PCI bridge will need
> > > to be coming off a memory bus that can sustain all of these and the CPU
> > > at once.
> > >
> > > At that point it really doesnt look much like a PC.
> >
> > How much raw speed do you think I can manage to get out of a really cool
> > n-way server from Compaq? I beleive we'll go for a Compaq server, as
> > that's what's been decided some time ago.
> Not that much. Alan's point is that you're pushing the limit of the
> memory bandwidth, not the number of CPUs. This is the single reason
> that high traffic websites either use some serious non-PC hardware (IBM
> Z-series, for example) or a large number of PCs in parallel to share
> the load.
> > I read something by Linus about linux scalability, and I beleive he said
> > that 'linux [2.4] scales good up to 4 cpus, but not that good futher on
> > [to 8?]'. Can anyone fill in the holes here?
> The number of CPUs really doesn't matter in this case. With several
> GigE cards memory bandwidth and latency is your main problem.

Interesting parallel...

In the last few years there have been multiple cases where people reported
benchmarks where a dual processir gave less thruput then a single
processor. In most cases, the single processor benchmark had saturated the
memory bandwidth and a second processor didn't make much difference.

This was on "cheap" multi-processors.

john alvord

To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to
More majordomo info at
Please read the FAQ at

 \ /
  Last update: 2005-03-22 13:12    [W:0.066 / U:0.012 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site