12900K Affinity Mask

[Nemo 1,305]

Please, If anyone with deeper knowledge could comment on my thoughts about AffinityMask usage in P3Dv5.3 using a 12900K processor.

[JobScheduler]
AffinityMask=16777215
P3DCoreAffinityMask=16733525
MainThreadScheduler=0
RenderThreadScheduler=2
FrameWorkerThreadScheduler=4

As far as I understood, the first entry "AffinityMask" is defined by the CPU itself and only depends on BIOS settings (HT ON or OFF). The second entry "P3DCoreAffinityMask" defines the Core usage in P3D. This line is where the adjustments should be made. I have currently set this to 16733525 which  corresponds to the second calculation line (see below). That means that P3D uses every second P-Core starting with Core 0 to Core 15.  All  E-Cores (16-23) remain active. The other entries "MainThreadScheduler" "RenderThreadScheduler" "FrameWorkerThreadScheduler" should be self-explanatory. According to BIN/DEC calculations (see below) it is important to know that CPU core counting is from right to left.

 

........................................................................................................................................................

12900K - HT ON in Bios

8 P Cores = 16 Threads   +   8 E cores = 8 Threads

16 (HT) + 8 Threads

1111 1111 1111 1111 1111 1111                              AffinityMask=16777215

(E Cores)             (P Cores)

CPU counts from Right to Left (0 to23)

23222120    19181716   15141312   1110 9 8    7 6 5 4    3 2 1 0

1111 1111 1111 1111 1111 1111 P3DCoreAffinityMask=16777215

 

1111 1111 0101 0101 0101 0101 P3DCoreAffinityMask=16733525

 

xxxx xxxx 1111 1111 1111 1111 P3DCoreAffinityMask=65535

 

xxxx xxxx 0101 0101 0101 0101 P3DCoreAffinityMask=21845

Edited December 25, 2021 by Nemo

[grandfred29 180]

I let it by default 

[dragon09 2]

I use 24532 with 8 cores and 16 threads.

 

James

[psolk 3,042]

Watching this as I am trying to figure this out for a 12700.  Do you want e-cores active or just P-Cores for P3D?  

Right now I am just at default which is 255  0  2 4  

[Nemo 1,305]

58 minutes ago, psolk said:

Watching this as I am trying to figure this out for a 12700.  Do you want e-cores active or just P-Cores for P3D?  

Right now I am just at default which is 255  0  2 4  

Currently, I let E cores active. P cores only half of them, which gives me better temperatures with the same performance (fps) and very smooth.

[micstatic 4,319]

2 hours ago, psolk said:

Watching this as I am trying to figure this out for a 12700.  Do you want e-cores active or just P-Cores for P3D?  

Right now I am just at default which is 255  0  2 4  

Hey man.  I'll be monitoring your progress.  I'm about a couple weeks out from doing a 12700k build also

[psolk 3,042]

16 minutes ago, micstatic said:

Hey man.  I'll be monitoring your progress.  I'm about a couple weeks out from doing a 12700k build also

Thus far highly impressed...  I am on a DDR4 board not DDR5 coupled with a 3080ti.

[micstatic 4,319]

11 minutes ago, psolk said:

Thus far highly impressed...  I am on a DDR4 board not DDR5 coupled with a 3080ti.

I’ve decided to go ddr4 also. Just don’t want to wait for ddr5 to come out with better specs and more availability. 

[micstatic 4,319]

At this point my decision comes down to 12900k vs 12700k