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Hi

that is typically a RAM memory w.r.t model complexity (mesh and number of DoF to large) issue.

Not much to do either by getting a bigger PC, iff v3.2 accepts to look after more RAM.
Or to update to a newer version and a newer PC,
finally by simplifying the model (fewer mesh elements)

--
Good luck
Ivar

Hi Ivar,
I have the same problem. My simulation is with RF module and 4e6 DOF. My computer has 64 gig of RAM with linux OS and I have comsol 4.3b. I tried to solve this memory issue by using out of core option of MUMPS solver. But didn't work. Could you please tell me why the out of core calculation doesn't work and what should I do?
Thanks,
Hamed

Dear Hamed,

Please see: www.comsol.com/blogs/much-memory-needed-solve-large-comsol-models/
for a rough idea of how much memory is needed to solve large models, and how to predict your memory requirements. Your problem should solve on your computer if you use the default solver settings for an RF model.

Dear Walter,

My simulation stopped running saying this error message too. However, my workstation has plenty RAMs left that is enough to run my simulation. I know this issue must be related to the RAMs but i think is something else not out of memory.
Here is more information. I have three COMSOL jobs running for about 2 weeks already and each one costs about 30GB of RAMs. (My workstation has 256GB of RAMs.) When one of my jobs stopped running and giving me the error of out of memory, I checked the total usage of memory from Task Manager showing that 64% of memory was using (about 64% X 256GB = 163GB) while the usage percentage on my account is 35% (90GB) which is actually how much my COMSOL jobs are using. It is obvious that the memory is enough to support my job but we can also see that there are about 73GB (163-90) leaking to nowhere.
Also I had this issue two months ago and this problem got be fixed by rebooting my workstation.
I have asked technicians from the vendor of my workstation and there is nothing wrong with hardware including RAMs.
Is that because I am running multiply COMSOL jobs for too long or some other things relevant to COMSOL but there is no other software is operating at the same time.

I hope I am not the only guy having this issue and if you have any thoughts, please let me know.
Any comments or suggestions would be greatly appreciated.

Best Regards,
Yi

Hello Yi,

You will want to contact our Support Team directly about this, as the description here certainly does sound like unusual behavior. It is something for which we would need to see a reproduce file for to begin our investigations. Now, if the error message that you're getting is actually this error (6192) then this would indicate you are using version 3.5a, a much earlier version of the software which is no longer supported.

For anyone still using 3.5a we do recommend that you upgrade to the latest supported version of the software, currently 5.2a. You are of course still welcome to use 3.5a if you wish, but we do encourage you to upgrade as we have put enormous effort into new features, better performance, and overall improvements in the software over the years.

More generally, about out-of-memory error messages, we now recommend that people first consult:
www.comsol.com/support/knowledgebase/1030/

Since the original message in this thread is about a version of the software that is now no longer on support, this thread will be closed for further comments, but will remain visible. If there are follow-on questions, please do feel free to open a new thread.

Best Regards,
Walter