Learning Forum

[AndyJP]

I can not believe my eyes. All the past year I was struggling with Driven Modal solver never using more than 2 cores at 100%, regardless of available 4+4 HPC licenses. I.e., I could get normal performance only in frequency Sweeps. Both in EDT2020R1, and in EDT2021R1.

The answer is: we had BASIC license, without optimetrics and other candies.

[manny]

Is this a question or a rant? Sounds like a rant to me.

[AndyJP]

That is an active disagreement with your policy. If you sell the product, sell it transparently please, without hidden limitations for second-sort customers.

[AndyJP]

//If it is a bug of license management, that it should be fixed ASAP in my opinion.

[manny]

Hi Andy All the cores that you specify are always used during the simulation and this is independent of enabling the Pro Pre Ent licensing option setting.Regardless of whether you set that option or not, if you check use automatic settings within HPC, and specify the desired number of cores to say 4, HFSS will use all of those 4 cores during adaptive meshing and also for the frequency sweep.Core usage information is also explicitly written out in the HFSS simulation profile.
Best Manny

[AndyJP]

I know how it is in theory and how it was starting from ver 15.
Earlier, I usually was setting 8 cores and 2 tasks; because in earlier versions 4 cores were giving out optimal performance. Anyway, during initial solution, before the sweep, only one task is used (no domain distribution).
As you see above, I had serious problems with CPU load distribution, where only 2 cores of 8 were loaded, and other 6 were idle almost all the time, except results copy/fetch phase, where OS distributes many small disk IO operations.
The day we upgraded to Premium, I finally got a uniform full load for all the CPU cores, and the corresponding performance.
So I have a natural suspicion that you updated DrivenModal solver operates differently under different types of license, regardless of available HPCs number.