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Old   May 12, 2011, 11:57
Smile Slow calculation
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Tom Janda
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Hi, I have one question.

My computer is have: 2 cores (Pentium i3, 8gb ram). Now I count the calculation with 1 200 000 cells. One iteration takes 1 minute, but all the calculation takes 3 days. I compute with settings Run mode: Serial. CPU usage is 30%, 60% of RAM. I using as a client Windows 7 and version Star CCm 4.04 64bit. My teacher say me that I have change settings from bios: Hypertreading turn off. It seems to me that both cores are not loaded at full power. Thanks for your answer.


Regards Tom
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Old   May 16, 2011, 02:25
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Matthias Fitl
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Good Morning,

Quote:
Originally Posted by tom.j.87 View Post
Hi, I have one question.

My computer is have: 2 cores (Pentium i3, 8gb ram). Now I count the calculation with 1 200 000 cells. One iteration takes 1 minute, but all the calculation takes 3 days. I compute with settings Run mode: Serial. CPU usage is 30%, 60% of RAM. I using as a client Windows 7 and version Star CCm 4.04 64bit. My teacher say me that I have change settings from bios: Hypertreading turn off. It seems to me that both cores are not loaded at full power. Thanks for your answer.


Regards Tom
  1. You need to start the paralell mode to use more than one core. You need either a HPC license or a second starccm+ license to do so.
  2. It is recomended to use n-1 cores for performance reasons. (n = number of cores available on computer)
  3. wit more the 1e6 cells and only 8GB RAM you will run into swaping leading to very poor performance, especially on Windows.
Conclusion: Setup a 4-8Core (!Licenses for starccm+) 16-32GB Ram fast harddisk system. If you or someone in your next to you is familar with Linux I would prefere to use this at leats for the server procves, but this is only a little bit more than personal experience. And I do not want to start a Linux-is-better-than-windows-or-the-other-way-around-war, defenetly.

CU,
Matthias
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