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rs October 18, 2007 02:40

RAM memory torun 2 million case
 
Hi,

I have to run a 2 million case on my machine. The machine is 32 bit with 4GB RAM but I could not able to run this case.

Even though we have 4Gb ram why we were not able to run a two million case?

Do we have any settings in the solver or the OS (windows XP SP2) which makes this run possible?

Your help is greatly apreciated.

Thanks

Harry October 18, 2007 14:14

Re: RAM memory torun 2 million case
 
On Windows you are limited to 3 gb per cpu so if the case needs more than that then you will need to run parallel. Also you need to watch for what physics you are using, the more the solver has to solve for the more memory it needs. If you are using STAR-CCM+ or V4 the number of faces in your model will be a consideration, especially if you are using a polyhedral mesh which contains significantly more faces than a hexa or tet mesh.


Anton Lyaskin October 19, 2007 04:31

Re: RAM memory torun 2 million case
 
Look for /3GB and /userva=xxx boot parameters at Microsoft internet site - this can help to free more memory for applications and allow an application to use more than 2Gb. Also stop all unnecessary services (do you really need Windows Update or NetMeeting or Print spooler while running a case?). 4Gb should be more than enough for 2 million cells, even if it's turbulent compressible. The only case can be if you have lot's of boundaries, like 1 million or more.

murash-v October 25, 2007 06:23

Re: RAM memory torun 2 million case
 
RAM size equal 4 GB is enough for 3.5 million cells with VOF.

azmir November 17, 2007 12:53

Re: RAM memory torun 2 million case
 
I'm not so sure... but the 32-bit windows could render your 4Gb RAM to a max of 3Gb effectively. You might have to change to 64-bit to be able to fully utilize the 4Gb.

Airfoil November 27, 2007 04:33

Re: RAM memory torun 2 million case
 
Try to compress all. I mean compress cell number, boundary and etc. You find this function in the tool menu. Hope this will help. Otherwise, as Azmir said, use XP 64 bit. I encourage you to use Linux 64bit.


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