Dan Hollis wrote:
>
> On Sat, 15 Jul 2000, Marc Mutz wrote:
> > Look, you are an the _very_ wrong track! You may have 6 or 7 PCI
> > _slots_, but you have only _one_ bus, i.e. only 133MB/sec bandwidth for
> > _all_ 6 or 7 devices. You will not get 90MB/sec real throughput with a
> > bus bandwidth of 133MB/sec! And the x86 architecture's memory bandwidth
> > is _tiny_ (BX chipset does one or two _dozen_ MB/sec random access, ie.
> > 12-24 MB/sec).
>
> No. BX does 180mbyte/sec (measured).
> K7 with Via KX133 does 262mbyte/sec (measured).
>
Read more carefully. I said _random_ access, not sequential.
> I'd like to get numbers for real alphas. The only alpha I was able to
> measure was Alphastation 200 4/233. A measly 71mbyte/sec on that piece of
> shit.
>
How old is that "shit" and what were the numbers then on x86?
> > > The alphas we have here have the same number of slots.
> > But not only one bus. They typically have 3 slots/bus.
>
> There are multiple pci bus x86 motherboards. Generally found on systems
> with >6 slots. I have seen x86 motherboards with 3 PCI buses, <interrupted>
I'd like to see how the x86 memory subsystem can saturate three (or only
two) 533MB/sec 64/66 PCI busses and still have the bandwidth to compute
a 90MB/sec stream of data.
> but the most
> ive seen on alpha or sparc is 2.
>
> -Dan
I never denied that such beasts exist. I just wanted to point out that a
x86 machine with those mobos would come close in price to the alpha
solution.
I simply can't imagine that there are no alpha boxen with more than 2
PCI busses. If I had a faster internet connection now, I'd check the web
site of alpha-processor Inc.
Marc
--
Marc Mutz <[EMAIL PROTECTED]> http://marc.mutz.com/Encryption-HOWTO/
University of Bielefeld, Dep. of Mathematics / Dep. of Physics
PGP-keyID's: 0xd46ce9ab (RSA), 0x7ae55b9e (DSS/DH)
