Frame Rate = 1fps...

[martinlest2 58]

I can only write down the symptoms as I have no idea what can be happening.

 

I have been flying the PMDG MD-11 and the previous two flights had problems with frame rate dropping from c.60fps to about 10fps, after 2/3 of the flight had gone just fine. I thought I had solved the problem as, when I looked at Process Monitor, FS9 was continuously searching for 'effects.cab' in the main FS9 folder (issue mentioned in a number of threads). I had had this issue before and created a 'dummy' effects.cab file (containing nothing relevant), but the file had disappeared somehow: copying it from backup immediately restored my frame rates to 60... (It is not clear why the missing - actually non-existent, no idea why FS9 searches for it) cab file would suddenly cause such a drop in fps: perhaps it didn't and the 'cure' was just a coincidence).

 

This may be a separate issue, but on this last flight, although the first 3/4 of it was fine, the fps suddenly plummeted to 1fps. If I paused the flight however, the frame rate immediately went back up to 60fps. Resume, and <1fps straight away. I closed all peripheral programmes, ActiveSky etc., but no change. I tried to run Process Monitor several times, but it froze up every time and refused to run - what clue might that give?

 

Task Monitor took ages to open, but when it did, it showed resources as fine - no excessive CPU usage by any programme, including FS9 and still 10GBs+ of free RAM. (So why did TM hang for so long?).

 

Finally, I used FS Navigator to move the MD-11 to a point back down the flight path when all was OK, and sure enough frame rates were good again. Unfortunately, loading the panel state with the autosaved .sav file, I could no longer open cockpit view and so I saved the flight and exited FS9.

 

Then I reloaded the flight (AutoSave + the saved PMDG panel state) at the point where I had had 1fps, but now there was no problem - I finished the flight (KMIA to TNCM) with no further issues. I had thought there might be a scenery error, but as I continued from the same area where I had been getting 1fps (and now 60fps), I suppose not.

 

Do these symptoms make any sense at all, and maybe lead anyone to a possible cause? Could it be an issue with the MD-11 - the three times I have had fps problems (as above), I have been flying that aircraft?

 

I'll continue with a few more flights with and without the MD-11 and see if any pattern emerges, but comments are very welcome meanwhile!

 

Thanks.

[martinlest2 58]

Anyone any ideas or experience of this? In summary: I am flying happily with fps around 60 and then, for up to about 20 seconds, frame rates fall to a juddery 3 or 4 (occasionally lower). I've always had this problem, on every PC on which I have ever run FS9 over the past 12 years or however long it is. I have been trying to get to the bottom of the problem for the same period, though have pretty much given up over the past few years.

 

It happens most flights as far as I can tell, though not 100% certain of that. If I am in the 2D cockpit it is not always obvious. I have never managed to pin anything down using Process Monitor or Task Manager - there's no obvious programme hogging the CPU. I have 16GBs of RAM, and there's always plenty available. The page file has been rebuilt on many occasions (corrupt?) - I use only SSDs now, so fragmentation isn't an issue.

 

I think the problem must come from within FS9.. any ideas from where though? I get it with no external programmes, such as Active Sky, or AI Separation running. Really no idea how to troubleshoot this any more - I have tried everything I can think of. (Plus it takes a long, long time to see any change, as the problem is sporadic and I need to take a whole flight each time to test any improvements). I wonder if it's aircraft related - flying the PMDG MD-11, as I have been all week, it is far worse than usual. I need to change to a different a/c and see if there's a difference.

 

Thanks.

[HenningL 2]

The only times i've experienced a drop to 2-4 fps were when the vmem (videocard memory) got filled up so there was no memory left for extra textures. I resolved the issue by reducing texture resolution for the addon airports that had many high res textures. I used a videocard with 512mb memory at the time and that was not enough for some addons.

 

How much vmem does your videocard have?

 

Henning

[martinlest2 58]

4GBs! :-)

[Skywatcher 133]

I've mentioned to you before, mentioned it in another thread, see if you can accomplish 1fps if you lock fps at 25. I think achieving 1fps at any stage will be a difficult task. Happy to be proved wrong! :wink:

[meesterlijk 25]

Does this only occur with the Md-11?

 

Try to look if the same thing happens with other aircraft. Then you know where to look first.

 

If it happens with other aircraft you should take a look at other programmes that are running. You already said that you closed everything else.

 

A year ago I suffered from heavy drops in fps as a result of some ai-traffic files. When flying in the northeast of the USA (mostly between New York en Washington DC) there is so much traffic my fps dropped dramatically. I found out that especially the packages of US airways Express was very hammering on my CPU.

 

Where do you have these drops? What packages do you use? There is also a difference between the aircraft you use for ai. Faib-aircraft for example are very demanding.

 

Just some thoughts.

[sascha 314]

Did you run Neumanix's dxtfixer? Missing alpha layers do cause stutters and fps loss, although the drop to 1 fps seems extreme. Do you still get this with default FS9?

[martinlest2 58]

Thanks for the comments..

 

Over the years I have run FS9 with different fps limits between 20 and unlimited. The sudden tiny frame rates isn't dependent on that, I am sure. 25fps is not one of the 'recommended' settings - a lot of technical threads about this out there but I can give it a try, easy enough to test. I haven't had 1fps again (I think it was less than that, but lower frame rates aren't registered of course!), but with the MD-11 it certainly seems to happen more often - it does happen with any a/c though, and at all parts of the world. I have used all kind of AI traffic over the years... again none of these seem to be the culprit as when I change them for new installations, the low fps sessions do not end. Nor when I have zero AI traffic set does anything different happen. In any case, I don't think the symptoms would lead me to think that is the problem: I fly for 10-15 minutes with fps showing at 59-60, then suddenly I get between 5 and15 seconds of around 5fps, then it clears and back to 60...

 

I have never flown out-of-the-box FS9 - I do have a clean installation I can try though and will let you know.

 

I have indeed tried dtxfixer and fixed quite a lot of bitmaps.. I spent quite some time on forums at one time on this. Some bitmaps refuse to be 'fixed' though and returned error notices, (or the programme just ignored them, I can't quite recall). Worth another look at that.. From when and where it happens I think texture loading is in some way the most likely cause..

[Skywatcher 133]

I'm convinced FS9 has some kind of memory management/optimization issues running at high fps. I've read many threads that could be caused by something like this and the issues all appear to be linked to users running at high fps. It's a theory but I've had it a long time and found nothing to disprove it and really found more material to actually enforce the theory. I'm not saying every problem is related to high fps but if I came across some of these issues with FS9 and was running 60fps+ the first thing I would do to troubleshoot is turn down the fps. If I still had the problem, then I would look elsewhere.

[Skywatcher 133]

One final point, many threads on "Can you tell the difference between 60 and 25fps?"

The answer really is "you can tell large differences only for a period"

You will find if you change between 60 and 25 and immediately start comparisons, you will see the difference, a big difference. So some people do this and then refuse to ever go back down because at 25fps the panning looked terribly jittery to them. This is the case only temporarily. The mind will adjust, become trained if you like to start accepting the jitters and compensate largely for it. After a short period if you run at 25fps it will look completely smooth. 60fps will still give a slightly smoother look if you eventually switch to it but the difference in reality is minimal. We compensate for color in the same way. The mind likes to see light as white. It will compensate to a fair degree to remove color casts caused by different colored light sources

[martinlest2 58]

Yes, I do see a big difference between 60fps (ultra-smooth panning) and 25fps (less so). That wouldn't be a deal-breaker, but as I say, I used to run FS9 at a much lower frame rate (for years) - I think 24 was the 'magic' number, but I have always had these short periods of stuttering whatever the fps limit I set, so sacrificing the nice smooth panning seems a bit pointless, though your comment that the brain would adjust may well be true.

 

But thanks anyway for the suggestion