FFPS:FFTF question

[paulwain 24]

Is there a video or anything to show this in action?

[Pete Dowson 558]

On 3/17/2018 at 5:59 PM, RALF9636 said:

That does not happen to me as long as my frame rates do not drop below my monitors refresh rate (with VSync on).

I cannot say for sure that other systems might not perform differently of course.

I have a three screen system with three projectors driving the scenery view on a 210 FOV curved screen. To do this I need 3 P3D windows. That severely affects frame rates. 

At a dense airport sich as EGLL or EHAM I have to reduce many settings just to get up near 20 fps. If I set either a frame rate limit or VSYNC it can't even manage that -- both settings reduce frame rates further when they cannot be easily achieved. So on the ground I need FFTF 0.01, and with that and some settings (like AI Traffic in particular) much lower than I'd really like, I can make it usable.

However, when flying, whether through clouds or not, I get up to 40-60 fps quite often, depending on the scenery below. And if I keep the FFTF that low I most certainly get "blurries", so much s that I prefer cloudy weather so i don't see too much terrain. And it is usually okay (less noticeable) at cruise altitudes of 30-40,000.

So, yes, the FFTF program will be useful. And there are bound to be others like me, with either very demanding needs or systems with less power than you.

Pete

 

[SteveW 1,792]

Adjusting FFTF shows no change to fps because it is simply apportioning time between collecting and exchanging. The bigger the FFTF the less time there is for exchanging (let's call it linkage) so the fps can rise a little that way as you select a larger fps (by showing a less complex scene) since it is making less linkage and hence in come's the stutter.

The faster the fps the less time for linkage and in a similar way to utilising the frame per frame event, the faster the fps of the system the more work the FFTF altering app does in stopping the sim to poke the new FFTF values.

Adding cores until we see no faster scenario loading or using high fps (over 30) would not suit the technique.

 

 

[SteveW 1,792]

If you notice I say "select a larger fps (by showing a less complex scene) " - more objects and bigger textures = less fps.

The GPU runs at the pace it always does Unlimited or locked on the slider the GPU get's on and draws the next frame as soon as the last is over at the pace it can. With Locked it's keeping a look ahead buffer, and with Unlimited the frames above the monitor refresh are lost. Adding in Vsync isn't a limit it simply instructs the DX engine to draw that frame for the approximate time the frame would represent, then draws another. What we can do is interrupt that process to increase the frame to frame time. During then background tasks continue as they always did (that is if the system is set correctly).

Changing FFTF does not mean we get more or less time to build frames. Adding in accoutrements like autogen, cklouds and special buildings decreases fps because it takes longer to draw the frame.

 

 

[RALF9636 1,998]

58 minutes ago, Pete Dowson said:

I have a three screen system with three projectors driving the scenery view on a 210 FOV curved screen. To do this I need 3 P3D windows. That severely affects frame rates. 

At a dense airport sich as EGLL or EHAM I have to reduce many settings just to get up near 20 fps. If I set either a frame rate limit or VSYNC it can't even manage that -- both settings reduce frame rates further when they cannot be easily achieved. So on the ground I need FFTF 0.01, and with that and some settings (like AI Traffic in particular) much lower than I'd really like, I can make it usable.

However, when flying, whether through clouds or not, I get up to 40-60 fps quite often, depending on the scenery below. And if I keep the FFTF that low I most certainly get "blurries", so much s that I prefer cloudy weather so i don't see too much terrain. And it is usually okay (less noticeable) at cruise altitudes of 30-40,000.

So, yes, the FFTF program will be useful. And there are bound to be others like me, with either very demanding needs or systems with less power than you.

Pete

 

Thanks for reporting.

I will keep this app in mind in case I should ever encounter blurries with my static FFTF=0.01 setting.

 

[GSalden 4,700]

2 hours ago, RALF9636 said:

Thanks for reporting.

I will keep this app in mind in case I should ever encounter blurries with my static FFTF=0.01 setting.

 

Good to read.

I did not try it but when flying perhaps the LOD radius could be set 1 notch higher when using a higher FFTF value.

regards

Gerard

[nealmac 260]

Quick question. I'm running P3Dv4 on a pretty old laptop right now. It doesn't have a good processor (an i5 2.8GHz or something like that) so as you can imagine I need to setting quite low in order to achieve a usable frame rate. Will this tool allow me to use higher settings without sacrificing my frame rate? I don't want to buy it if it's not going to help me. I'm kinda guessing this tool is more for PCs with a decent spec but if it would help me out then I'd definitely buy it.

[SteveW 1,792]

6 minutes ago, nealmac said:

Will this tool allow me to use higher settings without sacrificing my frame rate?

That's a great way of putting it.

In the end we see on the screen what we set so whatever settings we use we get the scene completed after so many frames.

More objects = lower fps, altering the ratio of FFTF and the LOD distance alters the amount of scene to be drawn with more detail which is altering fps.

So we ultimately can only gain fps by drawing less stuff at once. If we could gain fps without losing  something that would be like having a perpetual motion machine.

[SteveW 1,792]

If we turn on HT P3D will intensify use of the cores running the background tasks by two. With HT disabled the one task on that core might not be able to maximize its use. Having many cores means we don't need to worry so much but with few cores it could make the difference.

So rather than dividing up your cake in different ways you always have the same amount of cake. First, ensure you have the biggest cake to start with. From repeatable results on a specially programmed test harness I can see we need more cores up to an optimum to do more work. Too many cores introduces work lost to simple heat dissipation. Adding another process into the already creaking-under-the-load system to introduce settings into the running sim would be best on low fps and few cores.

Stands to reason - two guys digging a hole complete it quicker than one guy.

[GSalden 4,700]

1 hour ago, nealmac said:

Quick question. I'm running P3Dv4 on a pretty old laptop right now. It doesn't have a good processor (an i5 2.8GHz or something like that) so as you can imagine I need to setting quite low in order to achieve a usable frame rate. Will this tool allow me to use higher settings without sacrificing my frame rate? I don't want to buy it if it's not going to help me. I'm kinda guessing this tool is more for PCs with a decent spec but if it would help me out then I'd definitely buy it.

If I were you I first would OC the cpu to 4.0. This will give you extra fps.

The idea of this tool is maximum framerate on the ground ( detailed major airports )

Wheh flying most of us have enough fps room , but because of the low FFTF value very little cpu time is used for terrain loading. By using a higher FFTF value when flying we use that breathing space for more cpu terrain loafing time. Very simple and no rocker sience...

[newtie 540]

1 hour ago, SteveW said:

Stands to reason - two guys digging a hole complete it quicker than one guy.

Unless one has to wait while the other takes his turn 

[SteveW 1,792]

Haha. Precisely! I was careful not to say halves the time simply because no matter how big the hole they will get in each other's way inevitably at some stage. Whatever happens the main process of rendering is being interrupted by those shovellers - and the more there are the more they get in the way. Good one. So be careful not to have too many LPs and choose a responsible amount of sim objects for the hardware.

Edited March 21, 2018 by SteveW

[joepoway 241]

3 hours ago, GSalden said:

If I were you I first would OC the cpu to 4.0. This will give you extra fps.

The idea of this tool is maximum framerate on the ground ( detailed major airports )

Wheh flying most of us have enough fps room , but because of the low FFTF value very little cpu time is used for terrain loading. By using a higher FFTF value when flying we use that breathing space for more cpu terrain loafing time. Very simple and no rocker sience...

So if I understood this correctly on the ground at a busy airport by using FFTF = 0.01 it allots minimum time to terrain loading and maximizes CPU resources for everything it needs to do to maintain say 30 FPS smoothly on the ground. Now as you take off and gain altitude more and more scenery wants to come into your field of view (how much and how dense depends on slider settings) and now the minimum amount of time to load terrain (FFTF = 0.01) may become too short and blurries arise. So now by real-time increasing the FFTF to say 0.33 more time is allotted to scenery loading (not rendering as I understand it) and therefore blurries may be eliminated. However you are now reducing the amount of CPU capacity to do all that it needs to do for everything else (including rendering ?) and if you push the balance too far with too high an FFTF value you could get stutters (anything else ?) because you’ve exceeded your CPU overhead capacity.

Is this basically correct?

Thanks in advance

Joe

 

[joepoway 241]

15 hours ago, GSalden said:

Unlimited = 0.01 If you do not set a different value manually by the FFTF tweak inside the p3d.cfg file.

Locked means 0.33 If you do not set a different value manually by the FFTF tweak inside the p3d.cfg file. Therefore more terrain loading time and a lower framerate. Also because locked provides a more balanced / smoother framerate than unlimited the framerate of locked is slightly lower.

Eg : If you use locked 30 and set the program to 0.05 you will see almost the same franerate as with the default unlimited + Vsync on + 30 hrtz .

 

Thanks Gerard

Based on your last statement wouldn’t it be better to run locked 30 and force FFTF = 0.05 with a config mod instead of running unlimited and waisting those additional rendered frames that just get thrown away beyond the 30 Hz cycle?

I’ve always run unlimited because I get stutters at locked 30 but it may have always been because it forced my FFTF setting back to 0.33 which didn’t give me enough upside capacity whereas unlimited put me at 0.01?

BTW both scenarios have Vsync and TB turned on with my 30Hz monitor.

Does this make sense?

Thanks in advance

Joe

[mikeymike 366]

So why can’t we just meet in the middle with FFTF at 0.15??

 

bam. Best of both worlds?lol