PCI-64: how to find
Velocet
math at velocet.ca
Mon Feb 25 12:05:25 PST 2002
On Mon, Feb 25, 2002 at 02:11:03PM -0500, Patrick Geoffray's all...
> Velocet wrote:
>
> > 6.5us for Myrinet vs 32/33 pci being 8? Doesnt seem like the win that
> > it usually seems to be spec'd at. Are these #s accurate? ('out of the blue'
> > warning notwithstanding ;)
>
> Euh, yes, I think they are: 6.5 us with a 64/66 PCI, 8 us with a 32/33
> PCI (Lanai9 at 200 MHz). The main difference here is the PCI clock, the
> latency with a 64/33 MHz is between 7.5 and 8 us.
with what size packets? Wouldnt the latency reduce for a several hundred
byte packet just because the bus is that much wider? and twice the effect
for 66/64 pci? Is the cost of 64 gigabit cards vs 32 worth it for things
sensitive to latency?
/kc
>
> Patrick
>
> ----------------------------------------------------------
> | Patrick Geoffray, Ph.D. patrick at myri.com
> | Myricom, Inc. http://www.myri.com
> | Cell: 865-389-8852 685 Emory Valley Rd (B)
> | Phone: 865-425-0978 Oak Ridge, TN 37830
> ----------------------------------------------------------
>
--
Ken Chase, math at velocet.ca * Velocet Communications Inc. * Toronto, CANADA
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