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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 Sep 13, 2010, 6:46 p.m. EDT
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

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Posted: 1 decade ago Jul 12, 2010, 11:35 a.m. EDT
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 Jul 13, 2010, 5:21 a.m. EDT
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 Sep 11, 2010, 11:14 p.m. EDT
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 Sep 12, 2010, 4:02 a.m. EDT
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 Sep 13, 2010, 6:46 p.m. EDT
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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