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Time estimation and dual+ cores
Posted Aug 16, 2011, 4:13 a.m. EDT Studies & Solvers Version 4.0 2 Replies
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Hi again,
I wondered if there is any way to have COMSOL estimate the time of computation before/during running it. My model was run yesterday at around 2 pm here, and now it's 11 am and it's still running; I did refine the mesh, but the time of calculation has increased dramatically. In the progress bar it shows,
Nonlinear solver 0%
FMGRES 51%, 6.57 convergence, iteration parameter and value of 8511 and rising. Just about now another row has been added but it's all full of minuses..So I don't know if I want to wait for it to finish computing and do other work meanwhile, or cancel and make my mesh coarser, and run again.
My next question is this - in the bar at the bottom of the screen, where it shows memory use, it says
Physical memory 1.4 GB, Virtual memory 4.93 GB. My question is, will the program be able to divide its work between cores, for example If I run the same simulation in a quadruple-core computer, will it run faster?
It should be mentioned that I'm using version 4.0.0.937 on this computer.
Thanks for your time!
Shoval
I wondered if there is any way to have COMSOL estimate the time of computation before/during running it. My model was run yesterday at around 2 pm here, and now it's 11 am and it's still running; I did refine the mesh, but the time of calculation has increased dramatically. In the progress bar it shows,
Nonlinear solver 0%
FMGRES 51%, 6.57 convergence, iteration parameter and value of 8511 and rising. Just about now another row has been added but it's all full of minuses..So I don't know if I want to wait for it to finish computing and do other work meanwhile, or cancel and make my mesh coarser, and run again.
My next question is this - in the bar at the bottom of the screen, where it shows memory use, it says
Physical memory 1.4 GB, Virtual memory 4.93 GB. My question is, will the program be able to divide its work between cores, for example If I run the same simulation in a quadruple-core computer, will it run faster?
It should be mentioned that I'm using version 4.0.0.937 on this computer.
Thanks for your time!
Shoval
2 Replies Last Post Dec 29, 2014, 8:43 p.m. EST
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Posted:
1 decade ago
I think the virtual memory usage (OS has to swap the contents in between memory and HDD). You can take a look at the CPU usage and Disk Activity on Task Manager when commit memory is beyond the maximun physical memory.
Increase CPU power does help but NOT A LOT. Instead, increase physical memory size that can handle the simulation case without Virtual Memory activities during the simulation will speed up dramaticaly.
Also if your case has a larger in number of degrees of freedom (calculation points) and your PC has to use virtual memory, you can install a some solid-state HDD as virtual memory (entire HDD space). You should be get your case run much faster. Just based on my experiences.
Increase CPU power does help but NOT A LOT. Instead, increase physical memory size that can handle the simulation case without Virtual Memory activities during the simulation will speed up dramaticaly.
Also if your case has a larger in number of degrees of freedom (calculation points) and your PC has to use virtual memory, you can install a some solid-state HDD as virtual memory (entire HDD space). You should be get your case run much faster. Just based on my experiences.
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Posted:
10 years ago
Hi Zhao
Could you please tell me how to increase increase the physical memory size?
I am able to change the virtual memory allocation manually in config file which is just the limit for swapping the contents in between memory and HDD.
Could you please tell me how to increase increase the physical memory size?
I am able to change the virtual memory allocation manually in config file which is just the limit for swapping the contents in between memory and HDD.