A Frame-Time Analysis of P3D v3 -- Effects of CPU Affinity, Frame Lock, and HT

[Skywolf 992]

 

 

just like racing, don't "chase" the setup, wait for the track to come to you

 

Rob - I am going to use this statement for my market presentations.  It is is exactly the same in my industry too.  The way you said is perfect!!!!

 

Even I use the term setup but only difference is to change "track" to "entry".  Sounds super easy but it is all in the execution and it is super challenging.

 

Amazing!!!

[emshomar 0]

Very nice topic! I did exactly what was suggested on this thread: I added the AffinityMask tweak to 85, set the Frame Time Buffer thing to 0.01, had HyperThreatting on, set the Upper Frame Limit to 30 (although 33 seemed better) and applied the settings to the screenshots on the first post. I have an i7-4790k @4.8GHz and a GTX960 with 4GB.

 

I usually fly birds like AS A320 or PMDG B777. The difference is significantly better now, however I'm still experiencing stutters espacially during and after landing the fps goes nuts, jumping from 10 to 30. 

[Richard Sennett 2,499]

Very nice topic! I did exactly what was suggested on this thread: I added the AffinityMask tweak to 85, set the Frame Time Buffer thing to 0.01, had HyperThreatting on, set the Upper Frame Limit to 30 (although 33 seemed better) and applied the settings to the screenshots on the first post. I have an i7-4790k @4.8GHz and a GTX960 with 4GB.

 

I usually fly birds like AS A320 or PMDG B777. The difference is significantly better now, however I'm still experiencing stutters espacially during and after landing the fps goes nuts, jumping from 10 to 30. 

 

Your tweaks look good but try unlimited fps in P3D - I always run this with heavy hitters 

[GSalden 4,656]

Unlimited gave me better framerates than a locked one.

At a detailed airport with the framerate locked at 30-60 I had 17-28 fps.

With Unlimited I had 27-37 fps...

 

To get the best of both world I have set the NVI limiter to 30 and P3D to Unlimited...

 

Bear in mind that with a very detailed airport with AI traffic and lots of clouds there will always be some jitters here and there ...

[Richard Sennett 2,499]

Unlimited gave me better framerates than a locked one.

At a detailed airport with the framerate locked at 30-60 I had 17-28 fps.

 

" I have set the NVI limiter to 30 and P3D to Unlimited"

 

Funny you mention that for the first time I am trying this exact setting so far seems pretty good maybe a bit smoother when panning spot plane view - not that I have had a problem to begin with just always looking for that little extra tweak 

[GSalden 4,656]

Rich,

 

As I have 3 outside view monitors I carefully have to watch my settings.

Even with a Titan X

[godimaginedme 25]

Very nice topic! I did exactly what was suggested on this thread: I added the AffinityMask tweak to 85, set the Frame Time Buffer thing to 0.01, had HyperThreatting on, set the Upper Frame Limit to 30 (although 33 seemed better) and applied the settings to the screenshots on the first post. I have an i7-4790k @4.8GHz and a GTX960 with 4GB.

 

I usually fly birds like AS A320 or PMDG B777. The difference is significantly better now, however I'm still experiencing stutters espacially during and after landing the fps goes nuts, jumping from 10 to 30. 

 

 

Try going into the PMDG 777 settings menu in the FMC and select Sounds and have the sim preload all of the sounds. Before touchdown, the 777 can lag because it is loading the touchdown sequence sounds. That helped me.... It used to eat up a bunch of VAS, but since that's not much of a problem anymore, try it out!

[Richard Sennett 2,499]

Try going into the PMDG 777 settings menu in the FMC and select Sounds and have the sim preload all of the sounds. Before touchdown, the 777 can lag because it is loading the touchdown sequence sounds. That helped me.... It used to eat up a bunch of VAS, but since that's not much of a problem anymore, try it out!

 

Thanks for the hint

[Chocorua 112]

" I have set the NVI limiter to 30 and P3D to Unlimited"

 

Funny you mention that for the first time I am trying this exact setting so far seems pretty good maybe a bit smoother when panning spot plane view - not that I have had a problem to begin with just always looking for that little extra tweak 

I have gone to this setting as well, was quite surprised to see really stable FRs and smooth (er) performance. Like Rich, I didn't have much to complain about to start with. 

[Richard Sennett 2,499]

I have gone to this setting as well, was quite surprised to see really stable FRs and smooth (er) performance. Like Rich, I didn't have much to complain about to start with. 

 

After more investigation better off for me - must be the monitor each one has

[Tomaz Drnovsek 440]

If we set frame rate to unlimited in P3D and limit it to 30 in NVI, do we still get those extra frames that we get with unlimited setting in P3D vs. to locked? I read that Adaptive 1/2 refresh rate kinda works but it needs locked frames (30 or 60). So, does this setup (unlimited in P3D and locked in NVI) means frames are locked or unlimited?

[Chocorua 112]

For me frame rates remain solidly (mostly) at 30 due to the NI setting, but P3D is operating as if at unlimited, which, if I understand correctly, is more 'efficient' for the sim. Somewhere at LM site I saw a post stating something like this...that is, unlimited was a better internal choice than putting a restriction into it.

 

There, I'm sure I hacked that explanation rather well. :smile:  

After more investigation better off for me - must be the monitor each one has

Hmmm, had not thought about that being a possible factor.

[SteveW 1,792]

P3D is operating as if at unlimited, which, if I understand correctly, is more 'efficient' for the sim. Somewhere at LM site I saw a post stating something like this...that is, unlimited was a better internal choice than putting a restriction into it.

Depends what you want.

 

With P3D v3, There are two basic setups to use; one, uses the Unlimited setting, can utilise the triple buffer, and will VSync against the monitor refresh rate, or against the NI fps limit, the GPU fps aims for those, and two, with the other we have the fixed fps rate which creates look ahead frames based on an identical period between frames, and we would set that to a division of the monitor refresh or the NI fps limit.

 

So for example, we have a 60 Hz monitor refresh:

 

we can set NI limit to 30fps, then in the sim display settings we can set VSync and Triple buffer on, and set Unlimited

 

or we set VSync and triple buffer off, and set Fixed 30fps (which is 1/2 of the refresh in this case).

 

The fixed setting calms down the movement of other objects, because the sim physics is worked out from an exact time period. The computation creates an image with the plane and terrain where it should be.

 

The Unlimited setting increases jitter in other objects movement, because each frame is based on the time periods between the last few frames, and the image hardly ever draws the plane and the terrain in the location it should be in when we get to see it.

 

 

The fixed setting is not less efficient, it's just more exacting, and requires better fps overhead at all times than the unlimited/VSync/NI limit setup.

[Richard Sennett 2,499]

VSync and triple buffer off - fps unlimited is what works the best on my monitor - tried other settings not so good

[SteveW 1,792]

VSync and triple buffer off - fps unlimited is what works the best on my monitor - tried other settings not so good

The setups I was comparing above are to outline the difference with the fixed setting, and not a recommendation of setup.

 

But yes, this is a perfectly acceptable setup. Vsync off means it runs past the monitor refresh rate which is also going to be a good setup because there is no aiming for an fps as in the two basic setups I mentioned above.

 

..Those two setups are both fixed fps setups. The first one with vsync triple buffer, is very similar to the FSX 1/2 refresh setup favoured by many.

 

The vsync off, triple buffer off, fps limit on the slider, the more exacting setting, requires a more powerful machine. It's often thought that we can use a fixed fps setting of, say 30fps, if we see an unlimited performance of 35fps. In fact the amount of fps we need to see is more like double or more of what we want to set the fps to. Any kind of jitter in the flow can pull look ahead frames off of the buffer and they take time to reproduce. If this is the case it all comes to nothing. For example, if we don't run HT enabled, we run the risk of any other activity on LPs running the main sim jobs will sawtooth them with poor task switching. Whereas with HT enabled the jobscheduler will target the other LP and minimise the switching overhead. This requires an appropriate AM in the first place. So any kind of weakness in the setup will reduce the fixed setting to uselessness.