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Java heap space during parameter sweep

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Hello all,
I'm currently trying to run a parameter sweep on a model, and I keep having a "Java heap space" error.
I have 5 parameters that have 2 to 4 possible values each, making 216 combinations, hence 216 runs to perform with Comsol.
Is it too much ? Has anyone already encountered such issue ?
Thanks in advance
Y.

5 Replies Last Post 2010年9月13日 GMT-4 18:46
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

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Posted: 1 decade ago 2010年7月12日 GMT-4 11:35
Hi

there are a few dscussions about setting the java heap for heavy calculations, there are also info in the installation guide, and I blieve on the "Knowledge base", another way is to run COMSOL in server Client mode, this frees some RAM for the solver, as the client = pre-postprocessor can better be swapped out of RAM (usefull on laptop PC's)

Good luck
Ivar
Hi there are a few dscussions about setting the java heap for heavy calculations, there are also info in the installation guide, and I blieve on the "Knowledge base", another way is to run COMSOL in server Client mode, this frees some RAM for the solver, as the client = pre-postprocessor can better be swapped out of RAM (usefull on laptop PC's) Good luck Ivar

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Posted: 1 decade ago 2010年7月13日 GMT-4 05:21
Hi
Thanks for the answer Ivar.
I've read the references you mention, and I've tuned the size of the Java heap space, but it does not seem to work.
I've attached the error displayed by Comsol, does anyone know if it is a problem of memory while post-processing or during the calculation itself ?
Hi Thanks for the answer Ivar. I've read the references you mention, and I've tuned the size of the Java heap space, but it does not seem to work. I've attached the error displayed by Comsol, does anyone know if it is a problem of memory while post-processing or during the calculation itself ?


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Posted: 1 decade ago 2010年9月11日 GMT-4 23:14
I encountered the same question druing the parameter sweep. and I can not find the comsol.opt in comsol4.0a, so I want to ask you how can you fix it?

Thanks a bunch!
I encountered the same question druing the parameter sweep. and I can not find the comsol.opt in comsol4.0a, so I want to ask you how can you fix it? Thanks a bunch!

Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

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Posted: 1 decade ago 2010年9月12日 GMT-4 04:02
Hi

well I suppose "support" is the best place to get help then, as for the COMSOL code I do not have any other insider info than any other COMSOL user ;)

--
Good luck
Ivar
Hi well I suppose "support" is the best place to get help then, as for the COMSOL code I do not have any other insider info than any other COMSOL user ;) -- Good luck Ivar

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Posted: 1 decade ago 2010年9月13日 GMT-4 18:46
There is no comsol.opt file anymore for version 4.0. However, under \COMSOL40a\bin\win32 or \COMSOL40a\bin\win64 there are the files comsol.ini and comsolserver.ini. The maximum Java heap size is defined as the numeric value after -Xmx. The default is -Xmx1024m or 1024 megabytes.

There are other configuration options here which are specified in \COMSOL40a\java\win64\jre\bin\server\Xusage.txt or \COMSOL40a\java\win32\jre\bin\client\Xusage.txt.
There is no comsol.opt file anymore for version 4.0. However, under \COMSOL40a\bin\win32 or \COMSOL40a\bin\win64 there are the files comsol.ini and comsolserver.ini. The maximum Java heap size is defined as the numeric value after -Xmx. The default is -Xmx1024m or 1024 megabytes. There are other configuration options here which are specified in \COMSOL40a\java\win64\jre\bin\server\Xusage.txt or \COMSOL40a\java\win32\jre\bin\client\Xusage.txt.

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