DragonFly users List (threaded) for 2005-03
Re: Differences between AMD and Intel CPUs [was: Re: Dragonfly andHyperthreading....]
<EM1897@xxxxxxx> wrote in message news:02FB1A9B.3D7CFFE9.000424FF@xxxxxxxxxx
I'd much rather hear why you don't think that the bus
speed of the network adapter is a worthy criteria for
hardware selection than your opinion on my conduct.
Your reasoning is what gives you credibility; not your
name. It seems implausible that you don't understand
what a bottleneck a standard PCI bus is.
Just as a sidenote, I've been able to get 12.3MiBps each out of two standard
3c905ctx-m over a single PCI bus, with concurrent disk access (the
controller where network data was flowing to was also on the same bus, old
peecee). It just pays to investigate the options the hardware has for you,
and busmastering PCI with DMA certainly ups the average attained speed on
the 'slow' PCI bus. Of course, for Gigabit you are limited even by the
theoretical maximum transfer rate, but there's PCI-X out there, as you
mentioned, to alleviate that. When it comes to PCI-X, *all* boards are
relatively expensive, not just the AMD-powered ones. For instance, take a
look at the Tyan catalogue, it gives you a fairly good impression of server
mainboard price differences accross the three (four including the Athlon MP)
x86 server platforms.
Knowing that, it sounds ridiculous to claim that you can get a 3.2GHz P4
with a motherboard with PCI-X for under 300$. Unless it's a special deal
ofcourse, but special deals are not to be relied on when making proper cost
On the point of MP performance, everyone knows that only multithreaded
applications can really take advantage of it, and network stacks aren't
usually MP compatible. Knowing that high traffic means lots of interrupts,
it's also easy to see why an MP machine with non-MP-compatible network stack
performs worse than a UP machine.
Of course, to the 'dumb' manager who needs to get a set amount of
performance, this all doesn't matter as long as he gets it for a reasonable
price. Maybe it's here where we're shifting: the bulk of the list users tend
to go for the best solution, whereas said manager goes for the solution that
solves his problems the quickest at the lowest cost.
Now as a personal note to 'EM1897', please fix your client to properly
support message threads :).
-- Thomas E. Spanjaard