Troubleshooting crashes: Difference between revisions

== Possible causes ==

It's just as well possible that the FlightGear default settings are not supported with your hardware/drivers, so that the process will be killed by the OS because it's trying to do something not supported by your computer. If you are experiencing full system crashes, you should see [[System Crashes]] instead.

== Running FlightGear with minimal settings ==

In such cases, it is important to start up FlightGear with minimum settings, and start re-enabling features step by step to see what settings are supported by your hardware. You may want to [[Howto:Improve_framerates#Debugging.2Flog level|raise the FlightGear log level]], so that you get to see where the program stops starting/working, and what it was doing before it got terminated.

* The OSG on-screen stats

* The [[Built-in Profiler]]

It makes sense to keep using the ufo until you have optimized all settings accordingly and found out what's working and what isn't, i.e. don't even touch the aircraft settings or the location settings (airport, azimuth, offset) until you have really optimized everything else already.  

=== Performance targets ===

Generally, try to optimize FlightGear for at least 30+ fps before changing to a regular aircraft and/or location! Realistically, the ufo is not very representative - so that it would be better to aim for something in between 50-100 fps prior to switching to a more complex aircraft like the c172p for example. For instance, aircraft like the A380, IAR80, Concorde or 777 are known to require fairly powerful hardware.

=== Minimal Startup Profile ===

As mentioned, the point of the following settings is to disable '''everything''' that could have an effect on performance, to ensure that we get a working FlightGear window up and running with no eye candy at all, and maximum frame rate. Once that is working, features can be re-enabled step by step.

--prop:/sim/rendering/particles=0

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Using these settings, frame rates between 400-500 fps and a steady frame spacing (latency) of 3-11 ms, can be achieved on a notebook from 2007 (1024x768). Disabling wireframe mode lowers the framerate by about 50-80 fps. The window should be up and running (fully initialized) within 3-5 seconds, even on moderately old hardware (absent a navcache rebuild).

[[File:Screen shot minimal startup profile without textures 2.12.png|thumb |FG 2.12 zero eyecandy mode on 2009-era hardware (NVIDIA 260M)]]

[[File:Screen shot minimal startup profile with textures in 2.12.png|thumb |FG 2.12 minimal eye candy mode on 2009-era hardware (NVIDIA 260M)]]

As can be seen, additional resources can be freed by flying in areas without scenery (ocean tiles), by using simple aircraft like the ufo, and by using a HUD instead of a 2D/3D cockpit panel.

* [[Howto:Improve framerates]]

* [[Problematic Video Cards]]