CFD Online Discussion Forums

CFD Online Discussion Forums (
-   Hardware (
-   -   How to max the CPU usage? (

Christoph_84 May 3, 2011 05:48

How to max the CPU usage?

Iím using Fluent 13 (Academic License, no parallel Licenses!). On my old Workstation (win Vista) I got a CPU usage of 90% on all 4 cores. Now I got a new Workstation (i7 970 on openSUSE) there are 4 cores of the six are working (like it should be) but only with an average CUP usage of about 30%. How can I max this?


Patrick H June 7, 2011 18:55

the i7 970 is a six core, twelve thread processor so you're actually only using four out of twelve 'cores,' hence the ~30%. I don't think it will make any difference in processing speed/power but you can go into the BIOS and disable hyper-treading and then you should start seeing double the cpu usage because only the six physical cores will be used.

By the way, I also use an academic licence and I was wondering if you could shed some light on the maximum number of parallel processes (local machine) which is possible with this licence. Currently I have only be able to run a maximum of parallel four, which sounds like your limit as well, but would like to increase that to parallel six or greater if possible. Do you know of any Academic FLUENT licences which allow for greater then parallel 4 or should I just build a computer around that limitation?


RobertB June 8, 2011 15:45

The version of openSUSE we use isn't very smart about whether it is using real cores or virtual cores (i.e. it can assign two processes to the same physical core and leave others free). I would suggest you turn off hyperthreading. You may be OK if you are only using 4 of 6 cores but the hypertreading will buy you nothing anyway for this workload.

All times are GMT -4. The time now is 23:24.