[Beowulf] Home Beowulf

[Tiago Marques]

Hi,

I've run some tests with an i7 920 and OCZ DDR-1600 CAS7 and the
results were very good for bandwidth friendly benchmarks and I
definitely recommend you to stay away from the usual stock memory of
DDR3-1066 at CAS9.
About performance with CFD I have no idea. VASP liked particularly of
the extra bandwidth and yielded an extra 15% performance for RAM that
costed about the same. Other benchmarks may perform betters and others
won't care.
I'm somewhat new to this world but haven't found codes to which
latency matters. Games, as you might find on those websites, are the
main programs that benefit from reduced latency and there's only one
exception to the rule, which are UT3 based games. They heavily benefit
from bandwidth, which tells me they did some serious optimization to
benefit from it, which is the trend industry is taking as of late:
more bandwidth no matter the latency. (at least when it comes to
memory technology only).

Best regards


On 10/6/09, Dmitry Zaletnev <dzaletnev at yandex.ru> wrote:
>
>
>> > On Behalf Of Dmitry Zaletnev
>> >
>> > I just thinking about a 2-nodes Beowulf for a CFD application that
>> > reads/writes small amounts of data in random areas of RAM (non-cached
>> > translation). What would be the difference in overall performance (I
>> > suppose, due to the memory access time) between Q9650/ 8 GB DDR2-800
>> > and i7 920/ 6 GB DDR3-1866.
>> you probably mean "DDR3-1066".
> Tom, thank you for your answer, here I mean 1866 MHz, OCZ3P1866C7LV6GK kits.
> I expect their availability must grow up till the end of the winter when I'm
> going to finalize the construction of my home Beowulf. I'm slightly
> confused: the test results from the Corsair site tell about significant
> difference in performance between i7 with 1333 MHz memory and 1866 MHz
> memory, from other side Tom's hardware forum tells that the only parameter
> that matters is the latency and there's no difference between a low-latency
> 1333 MHz memory and 1600 MHz memory. But I'm afraid that chosing 1333 MHz
> memory now will eliminate the sense of future upgrade to Xeon (motherboard
> supports it) or Fermi-in-SLI.
>
> Best regards,
> Dmitry
> _______________________________________________
> Beowulf mailing list, Beowulf at beowulf.org sponsored by Penguin Computing
> To change your subscription (digest mode or unsubscribe) visit
> http://www.beowulf.org/mailman/listinfo/beowulf
>