[Beowulf] single machine with 500 GB of RAM

[Jörg Saßmannshausen]

Dear all,

Happy New Year!

I was wondering whether people on the list here have some first hand 
experiences with this. I have been asked to purchase a single machine with 
around 500 GB of RAM. We would not need more than 8 cores here. The job simply 
needs that much of memory (and even then it is running for 14 days). 

Now, with that amount of memory used by a single core, I would have thought 
that I need a fast memory interconnect, i.e. a high memory bandwidth. I was 
thinking of getting an Intel Sandybridge CPU (maybe a  E5-2650) for that 
machine and get a motherboard with can cope with that amount of memory. Does 
anybody happen to have some recommendations here or knows of potential 
pitfalls?

Also, in a related problem, how would I set the kernel.shmmni, kernel.shmall 
and kernel.shmmax values so I am not running out of memory handles here. I am 
still confused by that.

Any kind of advice here is much appreciated. Given it is an expensive piece of 
hardware we want to purchase I want to get it right.

All the best from a grey London

Jörg

-- 
*************************************************************
Jörg Saßmannshausen
University College London
Department of Chemistry
Gordon Street
London
WC1H 0AJ 

email: j.sassmannshausen at ucl.ac.uk
web: http://sassy.formativ.net

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