lack of swapspace

Kay Diederichs dikay at
Tue Oct 17 03:57:56 EST 1995

romao at wrote:
: Dear Xplorers
: I have a problem when trying to calculate maps of a 907 aa protein, with high
: resolution data. The machine I am using for the calculations is a SG Extreme,
: processor R4600, and has 64 MB memory.
: What happens is that when trying to calculate maps with the standard grid of
: 0.3 the process is killed due to lack of swapspace. However, even increasing 
: the total swapspace available to 155 MB, I can only calculate maps with a 
: larger grid of 0.4 (with the best data to 2.0A).
: I thought about buying a memory extension, but I would like to know if it will
: solve the problem, or if there might be another way .

Did you try to add virtual swap space?

Another way to solve the problem is to re-compile X-PLOR in single precision
This will approximately half the memory requirement for the FFT.
However, the SGI distribution uses SGI-specific FFT subroutines which do not
tolerate the transition to single precision (I  think), so you have
to use the HP distribution - it should build nicely on SGI machines (it
does under Linux).

Hope that helps, 
Kay Diederichs  		email: dikay at 
Universitaet Freiburg, Institut fuer Biophysik, Albertstr. 23 
D-79104 Freiburg, Germany   Tel. +49/(0)761/2035391 FAX +49/(0)761/2035016
and: Universitaet Konstanz, Fakuletaet fuer Biologie, Postfach 5560, M656
D-78434 Konstanz, Germany   Tel. +49/(0)7531/884049 FAX +49/(0)7531/883183

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