[Beowulf] Re: Beowulf Digest, Vol 43, Issue 37

[Steffen Grunewald]

On Wed, Sep 26, 2007 at 08:30:21AM -0700, David Mathog wrote:
> Tim Cutts <tjrc at sanger.ac.uk> wrote
> 
> 
> > I've heard of people making clusters out of Alphas running Linux  
> > before - can't remember where, but I did see someone had done it.
> 
> I used to have a 9 node DS10 cluster running linux.  Replaced it
> ages ago with a 20 node Athlon MP 2200+ cluster.  Each replacement
> node was faster for the sorts of code we run here (integer heavy,
> BLAST etc.) than the DS10 nodes.  And that was years ago. An
> Opteron or Core Duo would be scads faster yet.  Which is a long
> winded way of saying it probably doesn't make sense to build
> a cluster of Alpha's these days, no matter which OS you use.

Not if you can get it for free.
One should be aware that the IEEE floating point implementation on the
Alpha processors is different from that on X86 and everything that tries
to be backwards compatible, and different from the implementation on
Power processors as well. Thus a developer can gain quite a lot from
building, and running, FP applications on different platforms. And Alphas
have been one of the first affordable 64-bit platforms.

(BTW, our group started with about 10 Compaq XP1000 nodes, before moving
to Athlon MP2200+ - and this move was completely justified by the
particular app profile, and respective benchmarks.)

> That said, the one thing that was quite nice about the DS10s was that
> they held their value very well.  In fact, about half the price of
> the replacement cluster was obtained by selling the DS10s.  Now this
> was before the Alphacide, and it was a long time ago, but it may still
> be that there is a market for the pile of Alphas the original poster has
> on hand, in which case the best course is probably to sell those
> machines and buy as many modern x86 machines as possible with the proceeds.

Only a few weeks a go I received a request from a Turkish guy who got hold
of a dozen or so XP1000s, and wanted to install Debian on them (I had tried
to make FAI available for the Alpha architecture). While it's no problem 
to get a decent Linux distro, it becomes more and more difficult to have
a nice queueing system (we used to run Condor, but UW Madison has discontinued
support for Linux/Alpha quite some time ago, and even the last version isn't
available anymore) and other stuff (if it's closed source you're lost from
the very beginning, but even open source may lack architecture support)

Steffen

-- 
Steffen Grunewald * MPI Grav.Phys.(AEI) * Am Mühlenberg 1, D-14476 Potsdam
Cluster Admin * http://pandora.aei.mpg.de/merlin/ * http://www.aei.mpg.de/
* e-mail: steffen.grunewald(*)aei.mpg.de * +49-331-567-{fon:7233,fax:7298}
No Word/PPT mails - http://www.gnu.org/philosophy/no-word-attachments.html