RE: [myrinet] Re: RE: PCI bus speed

Hi Francesco,

I would agree at this point that Compaq Alpha based systems will have lower
Interconnect (Myrinet) performance than Intel-X86 based 64/66 systems.  You
may think I am being very specific and I am.  As we all know, the
Interconnect is only one piece of the overall system and your application
performance may not be affected depending on your app's compute versus
communication needs.  

As for Sparc based systems from Sun.  They do not have 64/66MHz systems
until you reach into the Ultra 60 workstation class or higher (As far as I
know).  

Note: If this comment is not correct, PLEASE correct me for the benefit of
this list.  I would not and will not intentionally make a false statement
about a fellow system vendor's product line.

I would argue/agree that these systems just like the upcoming Alpha 64/66
system are not traditional Beowulf machines.

tim

-----Original Message-----
From: Francesco Lovergine [mailto:[email protected]]
Sent: Thursday, August 30, 2001 3:06 AM
To: [email protected]
Subject: [myrinet] Re: RE: PCI bus speed


On Wed, Aug 29, 2001 at 03:40:01PM -0400, Tenhave, Tim wrote:
> Hi Keith,
> 
> The AlphaServer 4100 and all it flavors (4000, 4100, 4100LP) only offers
> 33MHz PCI.  All Alpha based products to date (August 2001) have either
been
> 32bit/33MHz or 64bit/33MHz or a combination of those two.
> 
> Compaq will not be shipping an Alpha processor based 64bit/66MHz PCI bus
> system until later this year.
> 
> I cannot comment on Alpha clones.
> 

So, we should comment that at this moment alpha-based beowulf clusters
are inherently worse as intel/sparc based, for throughput.
This is not true I think for high-end servers (but they are not used
as beowful PU :) generally). 
But for clones of course.

-- 
Francesco P. Lovergine