[Beowulf] Re: Beowulf Digest, Vol 53, Issue 1

[Mark Kosmowski]

At some point there a cost-benefit analysis needs to be performed.  If
my cluster at peak usage only uses 4 Gb RAM per CPU (I live in
single-core land still and do not yet differentiate between CPU and
core) and my nodes all have 16 Gb per CPU then I am wasting RAM
resources and would be better off buying new machines and physically
transferring the RAM to and from them or running more jobs each
distributed across fewer CPUs.  Or saving on my electricity bill and
powering down some nodes.

As heretical as this last sounds, I'm tempted to throw in the towel on
my PhD studies because I can no longer afford the power to run my
three node cluster at home.  Energy costs may end up being the straw
that breaks this camel's back.

Mark E. Kosmowski

> From: "Jon Aquilina" <eagles051387 at gmail.com>

>
> not sure if this applies to all kinds of senarios that clusters are used in
> but isnt the more ram you have the better?
>
> On 6/30/08, Vincent Diepeveen <diep at xs4all.nl> wrote:
> >
> > Toon,
> >
> > Can you drop a line on how important RAM is for weather forecasting in
> > latest type of calculations you're performing?
> >
> > Thanks,
> > Vincent
> >
> >
> > On Jun 30, 2008, at 8:20 PM, Toon Moene wrote:
> >
> > Jim Lux wrote:
> >>
> >> Yep.  And for good reason.  Even a big DoD job is still tiny in Nvidia's
> >>> scale of operations. We face this all the time with NASA work.
> >>>  Semiconductor manufacturers have no real reason to produce special purpose
> >>> or customized versions of their products for space use, because they can
> >>> sell all they can make to the consumer market. More than once, I've had a
> >>> phone call along the lines of this:
> >>> "Jim: I'm interested in your new ABC321 part."
> >>> "Rep: Great. I'll just send the NDA over and we can talk about it."
> >>> "Jim: Great, you have my email and my fax # is..."
> >>> "Rep: By the way, what sort of volume are you going to be using?"
> >>> "Jim: Oh, 10-12.."
> >>> "Rep: thousand per week, excellent..."
> >>> "Jim: No, a dozen pieces, total, lifetime buy, or at best maybe every
> >>> year."
> >>> "Rep: Oh...<dial tone>"
> >>> {Well, to be fair, it's not that bad, they don't hang up on you..
> >>>
> >>
> >> Since about a year, it's been clear to me that weather forecasting (i.e.,
> >> running a more or less sophisticated atmospheric model to provide weather
> >> predictions) is going to be "mainstream" in the sense that every business
> >> that needs such forecasts for its operations can simply run them in-house.
> >>
> >> Case in point:  I bought a $1100 HP box (the obvious target group being
> >> teenage downloaders) which performs the HIRLAM limited area model *on the
> >> grid that we used until October 2006* in December last year.
> >>
> >> It's about twice as slow as our then-operational 50-CPU Sun Fire 15K.
> >>
> >> I wonder what effect this will have on CPU developments ...
> >>
> >> --
> >> Toon Moene - e-mail: toon at moene.indiv.nluug.nl - phone: +31 346 214290
> >> Saturnushof 14, 3738 XG  Maartensdijk, The Netherlands
> >> At home: http://moene.indiv.nluug.nl/~toon/
> >> Progress of GNU Fortran: http://gcc.gnu.org/ml/gcc/2008-01/msg00009.html
> >>
> >
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>
>
>
> --
> Jonathan Aquilina