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GPS Lag

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GPS Lag

Postby bbuske » Wed Aug 29, 2018 9:38 pm

Hello,

I have a question... whenever I turn on the GPS on aircraft such as the C172, it takes forever to load the GPS data - which is completely fine. However, even after loading, the framerate drops to such a level, that the game freezes and has to be ended using task manager - unless you want to wait for like 2h. The same happens with any jet aircraft, that use integrated GPS in their flight controls systems (such as A320, A330, etc.).

I did use FSX before switching to Linux and it worked completely fine there. I also own a copy of X-Plane and it works completely fine there as well. GPS loads quickly an has no impact on flights or framerate. Any idea what causes it?
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Re: GPS Lag

Postby stuart » Thu Aug 30, 2018 2:00 pm

Hi Ben,

Ouch. That's not good. What are the specs of your system? Is it paging to disk?

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Re: GPS Lag

Postby bbuske » Thu Aug 30, 2018 2:13 pm

Hi,

It's an HP Pavillon Laptop with 4GB RRAM and and 512MB AMD Mullins chip. As I said, it's not high end, but it does allow me to fly even with full settings turned on, as long as I keep roads and 3D clouds disable. Framerate is decent and even over bigger cities, etc. there is no lag or drop in Framerate. It works perfectly fine. But for example if I take out the C172 and I am flying quietly and happily, then turn on GPS... it takes like 15 minutes to load. That part is ok for me. I guess it is loading all information and GPS data. I just start it up pre-flight, so I have it ready once in the air. However, the issue is, that once I turn it on, it finishes loading and frame rate drops to like 5 and even to 3fps. At times it would even freeze completely.

As soon as I turn of GPS again, all is fine and I can fly with no performance issues. The issue is, that if I am flying an Airliner, such as the Airbus, there is no way to turn it of. I have the map and all gps information right in front of me. Zooming in, lowering the range does help a little but not more than that. As I said, in both X-Plane 11 and FSX, the GPS, even in the 3D Panels loads instantly and can be operated with no lag. Plus, there is no drop in Framerate or something like that, when using it. Same machine, same specs, same airport and area. I have checked that.
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Re: GPS Lag

Postby legoboyvdlp » Thu Aug 30, 2018 3:02 pm

I take it for the Airbus you are talking about the Navigation Display screen? If so, turn off the WPT or ARPT layers if you are trying to use them - especially at higher map ranges, as it has to load all the waypoints / airports in that area. I usually just use the CSTR layer.

Are you using the IDG-A32X or A320neo?
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Re: GPS Lag

Postby Thorsten » Thu Aug 30, 2018 3:18 pm

It's an HP Pavillon Laptop with 4GB RRAM


Probably it's using swap memory, 4GB are way not enough to do the C-172p with a GPS (or worse, an Airbus).

As I said, in both X-Plane 11 and FSX, the GPS, even in the 3D Panels loads instantly and can be operated with no lag


irrelevant to first approximation, that's completely different software - we don't know how detailed the aircraft is in comparison, what else might be eating memory,...
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Re: GPS Lag

Postby bbuske » Thu Aug 30, 2018 3:33 pm

Hi Thorsten,

thanks for the reply.

I will have a look at the memory usage when turning on GPS to see, what is happening. FG memory usage has been average during normal operations. Let me have a check and I will let you know. Would raise Swap Memory fix or at least soften the issue? While trying to get some more RAM.
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Re: GPS Lag

Postby AndersG » Thu Aug 30, 2018 5:15 pm

Your are probably not running out of swap space on the harddisk so changing the amount will not do much - the problem is that paging memory contents to and from the harddisk is many orders of magnitude slower that accessing it in RAM. Try a simpler less heavy aircraft model. The J3 Cub might be slightly lighter but still very nice and there are plenty of much rougher and lighter models (e.g. my MFI-9, but there we talk beta if not alpha quality).
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Re: GPS Lag

Postby bbuske » Thu Aug 30, 2018 6:36 pm

Thanks for the advice.
I will have a look into that. At least while looking into getting more RAM... *sigh*
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Re: GPS Lag

Postby legoboyvdlp » Thu Aug 30, 2018 8:24 pm

You should hopefully at least be able to run the c172p with just the regular VFR instruments as well, if you make sure not to enable the GPS until you get it sorted out ;)

As for the A320, did you try disabling the layers on the navigation display as I mentioned?
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Re: GPS Lag

Postby bbuske » Thu Aug 30, 2018 8:39 pm

Hey,

yes, I did that. It works fine with the C172. I never need GPS... well most of the time, since I do my flight preparation before flying and using other means (ATPL and PPL here). Still, at times its handy, especially if my wife is flying and gets lost or if you quickly need to know nearest airport, etc.

That idea with the Airbus, worked well! Thanks!!!!! This made it flyable again!
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Re: GPS Lag

Postby legoboyvdlp » Fri Aug 31, 2018 10:55 am

That's great :)
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Re: GPS Lag

Postby bbuske » Fri Aug 31, 2018 4:53 pm

Smart idea actually. I take it that it works for other airliners like the Boeing as well. I gonna see and check!
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Re: GPS Lag

Postby Thorsten » Fri Aug 31, 2018 5:23 pm

I guess we'd all still be interested in learning whether it's really out of memory you're seeing - because if it's something else, that's worrisome and needs to be investigated.
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Re: GPS Lag

Postby Octal450 » Fri Aug 31, 2018 6:06 pm

If your using my Airbus (IDG-A32X/33X) be aware the whole ND is contained inside the aircraft itself (Models/Instruments/ND/canvas) wheras the old A320neo and Boeing planes uses one inside FGData.

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Re: GPS Lag

Postby bbuske » Fri Aug 31, 2018 7:59 pm

it0uchpods wrote in Fri Aug 31, 2018 6:06 pm:If your using my Airbus (IDG-A32X/33X) be aware the whole ND is contained inside the aircraft itself (Models/Instruments/ND/canvas) wheras the old A320neo and Boeing planes uses one inside FGData.

Josh


Yes, I am using yours. :) Because it's awesome. Great work there.
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