Stuck on E-cores for CPU workload on 12th gen Core i7, W11 22H2

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bikeaddict
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Re: Stuck on E-cores for CPU workload on 12th gen Core i7, W11 22H2

Post by bikeaddict »

meltz511 wrote: Wed Dec 13, 2023 3:32 pm I'd like to bump this thread.
I have a i9-14900kf, which is 16 E threads, and 16 performance threads. My advanced priority setting is set to higher.
No matter what, even if I tell it to use 32 threads; it will only use 16 threads of efficiency cores and not touch the performance cores.
I have used other applications which were able to use all the cores, so I know its possible.
The FahCore process is run at idle priority to limit the performance impact to the system while in use, so the OS probably decides to run the threads on the e-cores. You actually don't want to run 32 threads on an Intel hybrid CPU due to the way the GROMACS library works. All the threads will run only as fast as the slowest, so they should be run only on the p-cores.

Use FahControl and configure the slot to use 16 threads or less. Then use a utility like Process Lasso (https://bitsum.com/) to set the affinity of the FahCore_a8 process to run just on p-cores.
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