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RAM allocate Under Win 7 X64 bit Due core

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My Laptope has
T5450 1.6GHZ Due core CPU, 4G RAM
Win7 64 bit

when I ran COMSOL 4.0a, such as creating a huge mesh, I use -np 2 to use both the CPU.
but the memory control seem not works well, COMSOL shows: wroking set 1.42GB, Virtual memory: 1.88GB
there is still free memory in the system which is not allocated to COMSOL.

this delayed the process dramatically, like only finish 30% over night.



is there any one know how to adjust the memory allocating under win7?

thanks



12 Replies Last Post 22.03.2012, 02:07 GMT-4
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

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Posted: 1 decade ago 04.01.2011, 04:18 GMT-5
Hi

no need to use te -np 2 in v4 its there by default

you might have an issue with the graphics RAM shearing the main RAM, typical on laptops, so perhapsonly 2-3gB are available - OS and further fixed applications.

And use the "process monitor" of www.sysinternals.com to see what's really going on in there.

Now 4Gb is not that much, I often saturate my 48Gb for my models ;) Check also what COMSOl is saying it needs (lower right frame border),

Finally if you have a maintenance programme gt hands on the v4.1 it works better than 4.0

--
Good luck
Ivar
Hi no need to use te -np 2 in v4 its there by default you might have an issue with the graphics RAM shearing the main RAM, typical on laptops, so perhapsonly 2-3gB are available - OS and further fixed applications. And use the "process monitor" of www.sysinternals.com to see what's really going on in there. Now 4Gb is not that much, I often saturate my 48Gb for my models ;) Check also what COMSOl is saying it needs (lower right frame border), Finally if you have a maintenance programme gt hands on the v4.1 it works better than 4.0 -- Good luck Ivar

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Posted: 1 decade ago 04.01.2011, 04:52 GMT-5
Hi iVar,

thanks for your reply.

My laptop has separate 256M graph card which don't share memory with the main RAM.

when comsol is running my model, I checked the task manager, it shows the physical memory only used 2.4G, the other 1.6G is free.

I do downloaded the process monitor but don't how to use it, what should I look at?

the COMSOL saying Working set 1.68G, Virtual memory 3.2G.

Do you think this is because the CPU is due core, then each core can only use 2G memory?

BTW, when the mesh first start, both cpu is 100% load, and when it goes to 29%, one cpu's load drop to like 40%, the other keep at over 80%.

thanks

Ben
Hi iVar, thanks for your reply. My laptop has separate 256M graph card which don't share memory with the main RAM. when comsol is running my model, I checked the task manager, it shows the physical memory only used 2.4G, the other 1.6G is free. I do downloaded the process monitor but don't how to use it, what should I look at? the COMSOL saying Working set 1.68G, Virtual memory 3.2G. Do you think this is because the CPU is due core, then each core can only use 2G memory? BTW, when the mesh first start, both cpu is 100% load, and when it goes to 29%, one cpu's load drop to like 40%, the other keep at over 80%. thanks Ben

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

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Posted: 1 decade ago 04.01.2011, 05:08 GMT-5
Hi

are you sure you have the COMSOl 64 bit up and that you have the 64 bit of the OS is really on ?
I find your case puzzling, I have no RAM limitations with my version

the dual core does normally not change anything, could it be that some of your other applications are blocking or fragmenting the RAM in such a way that COMSOl cannot find it's due ? I often kill all small app I do not need when I run a large model. Another way to go on and gain some RAM is to run in client server mode, see the installation maual how to

--
Good luck
Ivar
Hi are you sure you have the COMSOl 64 bit up and that you have the 64 bit of the OS is really on ? I find your case puzzling, I have no RAM limitations with my version the dual core does normally not change anything, could it be that some of your other applications are blocking or fragmenting the RAM in such a way that COMSOl cannot find it's due ? I often kill all small app I do not need when I run a large model. Another way to go on and gain some RAM is to run in client server mode, see the installation maual how to -- Good luck Ivar

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Posted: 1 decade ago 04.01.2011, 08:41 GMT-5
Hi

My OS is win7 64bit.
and when I install COMSOL, I choose
windows (32bit)
windows (64-bit support)

BTW, in the task manager, the comsol.exe doesn't shows 32 bit.

another question is what is the status in the right bottom means? the working set and the virtual memory, my COMSOL always has larger virtual memory no matter open what and no matter how much physical memory left.

in addition, my software version is classkit, is this cause it?

thanks

Ben
Hi My OS is win7 64bit. and when I install COMSOL, I choose windows (32bit) windows (64-bit support) BTW, in the task manager, the comsol.exe doesn't shows 32 bit. another question is what is the status in the right bottom means? the working set and the virtual memory, my COMSOL always has larger virtual memory no matter open what and no matter how much physical memory left. in addition, my software version is classkit, is this cause it? thanks Ben

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

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Posted: 1 decade ago 04.01.2011, 10:14 GMT-5
Hi

I'm not aware of the specificities of a "classkit" licence, a I'm a "full user". The best is to submit such cases to "support" and to check agin on the forum and the KB with a "search" to see if sombody else has reported something similar.

--
Good luck
Ivar
Hi I'm not aware of the specificities of a "classkit" licence, a I'm a "full user". The best is to submit such cases to "support" and to check agin on the forum and the KB with a "search" to see if sombody else has reported something similar. -- Good luck Ivar

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Posted: 1 decade ago 20.03.2012, 12:26 GMT-4
Ivar,

How do you use 48 GB for a single model? My files seem to use a maximum of 10 GB even when I am heavily meshing. I have 64 GB of RAM available, and would much rather have COMSOL use the available RAM than access my much slower hard drive via virtual memory.

Is there a setting within COMSOL that allows it to use more memory or change the ratio of virtual to physical memory used?

Regards,
Azer
Ivar, How do you use 48 GB for a single model? My files seem to use a maximum of 10 GB even when I am heavily meshing. I have 64 GB of RAM available, and would much rather have COMSOL use the available RAM than access my much slower hard drive via virtual memory. Is there a setting within COMSOL that allows it to use more memory or change the ratio of virtual to physical memory used? Regards, Azer

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

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Posted: 1 decade ago 20.03.2012, 12:46 GMT-4
Hi

from what I know COMSOL uses all RAM available, if needed,
It's not that often I hit the 48Gb limit , mostly Im around 4-28 GB, but its easy to mesh very fine and get above ;)

--
Good luck
Ivar
Hi from what I know COMSOL uses all RAM available, if needed, It's not that often I hit the 48Gb limit , mostly Im around 4-28 GB, but its easy to mesh very fine and get above ;) -- Good luck Ivar

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Posted: 1 decade ago 20.03.2012, 17:15 GMT-4
COMSOL uses virtual memory instead of RAM. In the lower left hand corner, it claims that the working set is 2 GB, virtual memory is 2.2 GB, and my task manager confirms the working set of 2 GB.

I am running windows x64 and my COMSOL installation was 32 bit with 64 bit support. (I assume that this means it can use 64 bit capabilities and is not limited to 2 GB due to a 32 bit program).

Is there any way to tell COMSOL not to use virtual memory when all of that extra RAM is available?
COMSOL uses virtual memory instead of RAM. In the lower left hand corner, it claims that the working set is 2 GB, virtual memory is 2.2 GB, and my task manager confirms the working set of 2 GB. I am running windows x64 and my COMSOL installation was 32 bit with 64 bit support. (I assume that this means it can use 64 bit capabilities and is not limited to 2 GB due to a 32 bit program). Is there any way to tell COMSOL not to use virtual memory when all of that extra RAM is available?

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

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Posted: 1 decade ago 21.03.2012, 02:10 GMT-4
Hi

Well on my side I have a normal Win7-64 with a normal COMSOL 64 installation (all default) and while I run large Gb models my disk IO is hardly moving (process explorer details) so virtual RAM or not, I do not believe the OS is swapping that often, at least not for me ;)

But I'm in 4.2a that might be a difference

--
Good luck
Ivar
Hi Well on my side I have a normal Win7-64 with a normal COMSOL 64 installation (all default) and while I run large Gb models my disk IO is hardly moving (process explorer details) so virtual RAM or not, I do not believe the OS is swapping that often, at least not for me ;) But I'm in 4.2a that might be a difference -- Good luck Ivar

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Posted: 1 decade ago 21.03.2012, 11:30 GMT-4
Ivar,

I also have 4.2a. My version number is 4.2.0.228.

Do you know if the 64 bit version and the 32 bit version come on the same disk?
I suspect that my 32 bit version with 64 bit support is not the same as the 64 bit version.

~Azer
Ivar, I also have 4.2a. My version number is 4.2.0.228. Do you know if the 64 bit version and the 32 bit version come on the same disk? I suspect that my 32 bit version with 64 bit support is not the same as the 64 bit version. ~Azer

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

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Posted: 1 decade ago 21.03.2012, 13:47 GMT-4
Hi
everything was on the same disk for me, the best is to contact "support" for those issues. There is an update on the main site too

--
Good luck
Ivar
Hi everything was on the same disk for me, the best is to contact "support" for those issues. There is an update on the main site too -- Good luck Ivar

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Posted: 1 decade ago 22.03.2012, 02:07 GMT-4
Hi, All,
just some of my experience, when you run "comsol", try to choose the .exe file in folder: "COMSOL4xx\bin\win64"; this runs the 64bit version. it seems when you click the desktop icon , it opens 32bit comsol by default . at least, this helps us to ramps up our memory use from 2GB to 7GB.

regards,
Hi, All, just some of my experience, when you run "comsol", try to choose the .exe file in folder: "COMSOL4xx\bin\win64"; this runs the 64bit version. it seems when you click the desktop icon , it opens 32bit comsol by default . at least, this helps us to ramps up our memory use from 2GB to 7GB. regards,

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