Suggested affinity mask

[Jetblue291 0]

Hi guys, just curious if an affinity mask would be recommended for an 8700k with hyper threading on p3dv4.4, thanks!

[LRBS 947]

Some people use it some not.

In my case, I had issues with P3Dv4.4 and no AM worked for me. It turned out that I had a bad overclock in my setting that will give me problems related to stutters.

After I did overclock at 5.0 correctly now is smooth, no issues and no AM. Very difficult to find the correct combination for each version they come up with.

I would start with a clean config file and no overclock to see if you have any issues first. No computer is the same so is very difficult to get it correct.

[somiller 694]

I think you'll find that AF will improve performance when hyperthreading is enabled on the 8700k. The 8700k is 6 physical + 6 logical cores when HT is enabled...cores 0-11. At minimum I would mask off core 1 and core 3 so physical cores 0 and 2 are not encumbered by anything running on their logical cores. AF for that config would be 4085 which would yield 11 11 11 11 01 01 (1st core is represented by the rightmost pair). If you're running other apps along with P3D on the sim computer, you might consider masking off the last core pair, and confine those apps to that last core pair. In that case, you would use 1013 which yields 00 11 11 11 01 01. It may be that you don't have to mask the last core pair even if you run other apps, but I would certainly not allow those apps to run on the first two core pairs.

Best way I've found to test which affinity mask works best is to run FRAPS to log frametimes. The best setting for your computer will result in consistent frametimes with very few long frames (stutters)

Kind Regards,

[Jetblue291 0]

Thanks for the replies guys. My oc is stable at 5.0 with ht enabled, has been for quite some time now. I go back to the days of endless tweaks on FSX and I’m just getting back into flying with v4.4 with a 1080ti so I was curious if the (old) rules still applied.

[AnkH 2,262]

Same CPU with 5.0GHz here and since early FSX days, I always got the best results with an AM that disables the hyper-threaded cores, basically mimicking a HT off situation. Means: 010101010101 and so on. For my 3770K it was AM=85, now for my 8700K it is AM=1365.

In addition, I now use bat files that move all addons (where this method works) off from core0 to the last two cores (core4 and core5). Means: ActiveSky, REX, ProATC/X all run on those two cores only, leaving core0 entirely to P3D (and UT2).

[Axis3600 50]

Is there a tutorial to know how to put the add-on as active sky, REX etc with a BAT file?

I would like to try to see what it gives.

[GSalden 4,656]

http://www.codelegend.com/forums/viewtopic.php?f=2&t=632

[Axis3600 50]

Ok good thank you

[Nyxx 6,993]

8 hours ago, killthespam said:

Some people use it some not.

In my case, I had issues with P3Dv4.4 and no AM worked for me. It turned out that I had a bad overclock in my setting that will give me problems related to stutters.

After I did overclock at 5.0 correctly now is smooth, no issues and no AM. Very difficult to find the correct combination for each version they come up with.

I would start with a clean config file and no overclock to see if you have any issues first. No computer is the same so is very difficult to get it correct.

The perfect sum up Alex.

[Nyxx 6,993]

8 hours ago, somiller said:

I think you'll find that AF will improve performance when hyperthreading is enabled on the 8700k. The 8700k is 6 physical + 6 logical cores when HT is enabled...cores 0-11. At minimum I would mask off core 1 and core 3 so physical cores 0 and 2 are not encumbered by anything running on their logical cores. AF for that config would be 4085 which would yield 11 11 11 11 01 01 (1st core is represented by the rightmost pair). If you're running other apps along with P3D on the sim computer, you might consider masking off the last core pair, and confine those apps to that last core pair. In that case, you would use 1013 which yields 00 11 11 11 01 01. It may be that you don't have to mask the last core pair even if you run other apps, but I would certainly not allow those apps to run on the first two core pairs.

Best way I've found to test which affinity mask works best is to run FRAPS to log frametimes. The best setting for your computer will result in consistent frametimes with very few long frames (stutters)

Kind Regards,

Nice.

I use AM and let all other apps run only on 1 core pair. But just to add it's not just about FPS look for texture loading. The problem is every PC is different. It's a mind field. I suggest you look at if you start using an AM, watch what core pair P3D are using the least there the ones I now have for all other apps running on.

Edited April 9, 2019 by Nyxx

[ng0057a5 6]

AM and HT were mandatory with my old i7 3770K.

As my new i7 9700K has 8 physical cores, no need and performances are just insane 😊

Edited April 9, 2019 by ng0057a5

[AnkH 2,262]

Not really surprising as the 9700K does not even offer HT... Without HT, no AM is needed, that is nothing really new...

[Jetblue291 0]

Well just to report I’ve had a noticeable improvement with AM=1365, basically running on the physical cores, moving other apps to 9 and 11. I’m must admit I’m very surprised how good the result was considering my previous 4 core 8 thread systems never really seemed to benefit from an AM, so thanks for the tips I will continue to test to make sure it’s not my snake oiled mind playing tricks on me!!

[somiller 694]

3 hours ago, Jetblue291 said:

Well just to report I’ve had a noticeable improvement with AM=1365, basically running on the physical cores, moving other apps to 9 and 11. I’m must admit I’m very surprised how good the result was considering my previous 4 core 8 thread systems never really seemed to benefit from an AM, so thanks for the tips I will continue to test to make sure it’s not my snake oiled mind playing tricks on me!!

Good for you...again, if you're running additional apps on your sim computer and you move those off of physical cores 1 and 2 it will get even better.

Kind Regards,

[pegruder 65]

I've always had the best performance lately with just a stock p3d settings file (no AM).  I avg 20-22fps in high density areas like NYC, and 30+ everywhere else.  Most sliders to the right except special effects - found that one to be a big FPS killer so i dropped it.