[gmx-users] GROMACS in parallel on Dual CPU Linux machine

[Anton Feenstra]

Pratul K. Agarwal wrote:
[...]
> Has anybody seen this before (the effect of temperature on 
> parallel jobs)?

2 single or one parallel jobs will (should?) give identical CPU
load, so in that case your problem is probably not heating.

One thing I could think of, is that the communication somehow is
more temperature sensitive than the calculation, meaning that given
a certain CPU temperature, calculations are still acturate but the
communication becomes flaky. Never heard this reported, though, just
something I thought of just now.

Putting your machine in a cold room is a good idea, always, but may
not be sufficient if the heat doesn't come out of your box. Be sure
to have unrestricted airflow in the box (bundle *all* cables out of
the way!), and install a fan in all the holes your box has. The
power supply fan only usually is not enough, certainly for a dual box.


-- 
Groetjes,

Anton
  _____________ _______________________________________________________
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|  _   _  ___,| K. Anton Feenstra                                     |
| / \ / \'| | | Dept. of Pharmacochem. - Vrije Universiteit Amsterdam |
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