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Controlling your aircraft, using the autopilot etc.

Re: GPS Lag

Postby Octal450 » Sat Sep 01, 2018 1:09 am

Thanks Ben!

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Re: GPS Lag

Postby stuart » Sat Sep 01, 2018 4:00 pm

I did some tests myself. Switching on the GPS on the 172 dropped my framerate from around 33fps to 26fps, which is a fairly substantial reduction. However, I'm not seeing any significant freeze like Ben is, and I don't see a significant memory usage hike which might lead to paging.

I also don't see anything pathological at first glance in the code (not that I'd expect to). It's running a loop every 0.3 seconds and doing lots of property I/O.

Sorry Ben - I don't think there's a simply magic bullet here. At least none I can see.

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Re: GPS Lag

Postby bbuske » Sat Sep 01, 2018 4:16 pm

Thanks for looking into it further stuart.

I have tried the C172 after a reboot and it worked with just a drop of framerate and some short freezing for about 2 minutes. I guess it is the time it takes for loading initially. If I turn GPS off and on afterwards, the drop in framerate remains but the freezing is gone.

The freezing is biggest with I think it was the 1900D when GPS is turned on and pretty much won't go away. Also there was an issue with the Airbus, but that could be softened with the aforementioned tips.

I have not yet looked at the memory nor have I tried to run FG in a window. I will do some troubleshooting here this weekend.
Thanks again for trying!


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