Basically, AM is worthless in P3d2. No shock there. Also, I undid the block on core 0 and that did nothing either good or bad to performance.

As I said in another post, P3D2 seems can only use three cores. When I used AM=15, I saw core 0 goes 100% and core 1-3 went down to 60-70%, so I still ended up using 75% of the total CPU. Only when P3D2 was starting a flight I saw all cores maxed out. Overall I saw no benefits of having AM=15 so I removed the AM in CFG file to let P3D2 runs on core 1-3 only.

 

This appears to be consistent with what LM said that they optimized P3D2 to run three threads, each per core.

Actually, they said that P3d2 will use as many cores as you have. If you have more than 4 cores, it will leave core 0 for use by the OS and other apps. I have 12 physical cores and P3d2 uses 11 of them by default. If I force it to also use core 0, it has no impact on performance one way or the other.

that could be true, but still when I set AM=15, I can max out core 0 but the rest of the three cores don't pick up any extra load. By default, P3D2 can max out all three cores 1-3. So it appears to me that although P3D2 can use many cores, there is still one core that works the hardest and becomes limiting when it gets maxed out, kind of defeating the purpose of having more than three cores running...

 I have 12 physical cores

 

Do you have a Opteron in your flight sim rig? 

 

Edit: Just saw your specs.. Xeon.. Same difference.. Lucky you!

that could be true, but still when I set AM=15, I can max out core 0 but the rest of the three cores don't pick up any extra load. By default, P3D2 can max out all three cores 1-3. So it appears to me that although P3D2 can use many cores, there is still one core that works the hardest and becomes limiting when it gets maxed out, kind of defeating the purpose of having more than three cores running...

 

 

I was coming to post just this, I see exactly the same behavior after testing both ways for a day or so. I really tried to do it LM's way, to see if they were right, and also to have tested thoroughly myself in case they were wrong.

 

Without an AM set, the primary core will sit at 100% utilization, This translates into behavior no different than with FSX.

 

So for me anyway, AM is just as much a requirement as it ever was. I think some guy named Dave or Dexter or something said the same 2 days ago  

Agree that there is something wonky with the AffinityMask.

 

For me, it's easily reproducible. Start in the default flight situation with the F22 on the runway. Hit the throttle, take off, and fly a pattern around the airport. If I don't add the AffinityMask setting in the config file, the textures take a while to load. They are a bit of a blurry mess.

 

If I add that setting, the textures are perfectly sharp no matter how fast or crazy I fly ("Maverick!"). Even switching views won't cause blurry textures. It's about 100x better than FSX for me.

 

It's not placebo. It really is night and day. I went through the comparison about 10 times. Of course, it's entirely possible it's an oddity specific to my system config.

Do you have a Opteron in your flight sim rig? 

 

Edit: Just saw your specs.. Xeon.. Same difference.. Lucky you!

The computer was original purchased for video editing, but I now use it for routine stuff and flight simming. P3d 1.4 would use 5 or 6 cores, but P3d2 uses them all, as long as you use Process Explorer to let it use core 0.

Agree that there is something wonky with the AffinityMask.

 

For me, it's easily reproducible. Start in the default flight situation with the F22 on the runway. Hit the throttle, take off, and fly a pattern around the airport. If I don't add the AffinityMask setting in the config file, the textures take a while to load. They are a bit of a blurry mess.

 

If I add that setting, the textures are perfectly sharp no matter how fast or crazy I fly ("Maverick!"). Even switching views won't cause blurry textures. It's about 100x better than FSX for me.

 

It's not placebo. It really is night and day. I went through the comparison about 10 times. Of course, it's entirely possible it's an oddity specific to my system config.

 

 

Same here on an I7 920 with HT disabled. Night and day. Flying or even worse slewing without the affinity mask set to 14 always ended in a blurry mess. With the affinity mask set, textures remain crisp whatever I do.

If you want to see why, have a look at your core utilization without AM set.

 

Having a core completely saturated, like the primary core will be without an AM (14 or 84) set, is definitely not a good thing. Any threads that are on the core will be contending for time, and you will without a doubt feel/see that while the simulation is running.

 

This is really no different than it was with FSX.

I want to happily report here that AM=14 did wonders to solve my texture loading problem! It's so good it's almost unbelievable. I'm really surprised by this since without adding AM the P3D2 already runs on core1-3, so adding AM=14 seems to be redundant.

 

However, things are indeed different when I actually added AM=14 into the CFG file. Under my near "maxed-out" settings, in a very autogen heavy area like San Francisco, without any AM core1 is constantly maxed at 100%, and core 2 + core 3 each runs close to 90%-100%. And I easily get slow or even stuck on loading ground textures (i.e. blurry!).

 

Setting AM=15 doesn't help the texture loading problem at all. Now core 0 runs a constant 100% and the rest three cores each runs around 60%. And I remember that Windows uses core 0 to so maxing out core 0 is a bad idea.

 

Now, with AM=14, what I have got appears to be the best distribution of core-loading: core 1 at 100%, core 2, 3 and 0 each at like 60%, 50% and 40%. I don't know why core 0 gets loaded under AM=14, but by all means my blurry ground texture problem is now completely gone! This is exactly the same results Jimmy reported couple posts above.

 

When I switch views I still can get very blurry ground textures, but instead of waiting minutes or forever for P3D2 to reload them now P3D2 reloads them in seconds or even less. I'm so happy about this.. Life with P3D2 keeps getting better!

Setting AM=14 makes a significant difference for me. I am very curious to know why since this is supposedly the default. Its as if PD3 forgets it should be doing AM=14 unless explicitly set in the config file. Any ideas?

I saw no performance difference with AF settings and saw zero difference monitoring the cores enabled or disabled. I run 2700K with HT enabled so AF=84 is my setting. P3D seems to spread the load across three cores leaving the first open by default for me making this tweak redundant. It's odd that some are noticing otherwise.   

 

I have not tried AF=252 which should use the virtual cores. I'm interested to see if this makes a difference.

I just got P3D installed and I have never tweaked FSX, so I am asking this question from a base of no tweaking knowledge.  I am looking in the Prepar3D file within the following path:

c:/Users/Owner/AppData/Roaming/Lockheed Martin/Prepar3d v2

 

I am unable to find anything stating:

[JOBSCHEDULER]
AffinityMask=n

 

Can someone please assist in helping me locate this.  Thanks.

Its not there. You must add it to the cfg