FPS Dropsime goes on

[AVA117]

I don't know why but each time I install a fresh installation of FlightGear it disappears however, as time goes on when I begin flying into places my FPS drops dramatically.. no you can't tell me that its because I'm flying on different places I observed this bizarre behavior on my common flights from LOWI to EGKK. Could this be the cause of FlightGear having to load all of the scenery I have downloaded?

[wkitty42]

only the scenery needed for your settings is loaded... if you have heavy scenery (a lot of details like buildings, roads, power pylons) then it is possible that it will slow your system down...

there are other things that will slow it down, as well... try turning off the animated jetways... something has changed in the last several months and they were causing quite the slowdown on my system... turning them off gave me back some speed and FPS...

if you don't use the AI craft and watch or fly with them, turn them off, too... they also consume CPU processing time which can also lead to lower FPS than desired...

[Hooray]

My suggestion would be to check if the problem can be reproduced when using areas for which you have already downloaded all scenery/terrain - alternatively, using an ocean-only area

[AVA117]

My suggestion would be to check if the problem can be reproduced when using areas for which you have already downloaded all scenery/terrain - alternatively, using an ocean-only area

I already mentioned this.

-I disabled animated jetways
-No A.I traffic
-I disabled buildings, pylons, roads and etc..
-When gaming, I disable all possible background processes

and I'm still getting occasional FPS drop. I can play smoothly before this on full details.

[Hooray]

even without the features you said you have explicitly disabled, there may still be terrain shown (and thus, downloaded).
So, to be sure what is going on, I would suggest to proceed step-by-step and exclude potential issues that way.
Otherwise, it is going to take tons of time to troubleshoot this remotely, because it is next to impossible to guess what you are doing/seeing.

Given that you said, that it worked correctly before, there's at least light on the horizon ...

Besides, "ocassional fps drops" - what does that mean in numbers specifically (some "lag" is to be expected depending on the kind of features you're using and your specific local configuration)

[wkitty42]

Besides, "ocassional fps drops" - what does that mean in numbers specifically (some "lag" is to be expected depending on the kind of features you're using and your specific local configuration)

we won't even look at what happens when on MP and a heavy craft comes into range and how that can affect the local operation of the sim

[AVA117]

Okay, when flying on multiplayer I do it so my flight counts on the FGTracker or something and to be honest I rarely meet someone in the ground or in the air when I do so they're like 70-90nm away too far for me to see them.

And I don't have any solutions that I can think of anymore maybe its the way FlightGear behaves (at least on my part).

[wkitty42]

yep, probably...

on my MP comment... just like you can't see them in the pilot list until they come into some range, the craft will load even if you cannot visually see it in the distance... if it is listed in the pilot list, it is loaded... this is why some folks have removed these heavily detailed craft from their systems and just use the blue/yellow glider to represent those craft...

FWIW: i looked back over the topic and i don't see your machine specs listed... what CPU and GPU are you using? please include their speed and RAM, as well...

as an example:

• CPU: AMD Vishera Black FX8350 8-core 4Ghz
• GPU: NVIDIA GeForce GT 730 w/ 1G RAM
• FGFS has 2623272k RAM in use (after 43 hours continuous operation)
• FGFS is floating between 8% and 11% CPU usage
• GPU usage is about 34%
• in the UFO
• hovering over the tower at EGLL (900 feet ASL)
• just sitting and watching AI craft moving about
• zoomed to FOV 22 looking to East end of runways (about -11 degree pitch)
  
  ----- F10->View->Rendering Options -----
• Wireframe is off
• Point Sprites is on
• Throttle Frame Rate is off
• Compensate Field of View is off
• Animated Jetways is off
• Pylons and Power Lines are Enabled
• Detailed Roads and Railways are Enabled
• Buildings is set to OpenStreetMap Data
• Random Scenery Objects is Disabled
• Vegetation is Low Density
• Vegetation Shadows are Disabled
• Scenery Objects are Enabled
• Terrain Textures is Region-Specific
• Shader Effects is set to Custom
• all shader options are full right
• Particles (smoke, dust, spray) is on
• Precipitation is on
• 3D clouds is off
• Atmospheric Light Scattering is on
  
  ----- F10->View->View Options -----
• all view options are on except 2D panel and autohide menu bar
  
  ----- F10->View->Cockpit View Options -----
• all cockpit options are enabled/default
  
  ----- F10->View->Adjust LOD Ranges -----
• LOD ranges are
  • Scenery: 1500, 30000, 75000
  • AI/MP Craft: 92600 meters (so we can visually see craft at 50 nautical miles [1])
  • AI/MP Interior: 50
• we're using Detailed Weather & click on the [OK] button to start it when first starting the sim
• we're using live METAR data (--enable-real-weather-fetch)
• we're using Terrain Effects and Terrain Presampling in the Advanced Weather Config. everything else in there is default
• we have the CTRL-m map opened, positioned to far left of screen, zoom level 9 at the moment
• we use the official scenery from terrasync
• terrasync is turned off (we have the entire world and update externally via terrasync.py)
• we do not load the aircraft carrier AI scenario (--prop:/sim/ai/scenario=none [2])
• we turn off the voices for tutorials and the AIATC (--prop:/sim/sound/voices/enabled=false)
• we have the AI dynamic wake enabled and set to 5 miles (--prop:/fdm/ai-wake/enabled=true --prop:/fdm/ai-wake/max-radius-nm=5)
• we're using --prop:/sim/rendering/multithreading-mode=CullThreadPerCameraDrawThreadPerContext

that's pretty much everything i can think of but i'm sure there are other settings that may come into play... anyway, with all of this, we're seeing an average of 11fps...


[1] we should easily be able to see the landing lights of approaching craft at this distance.
[2] gives an error about not finding the "none" scenario but that's ok because it doesn't load the Nimitz and Eisenhower by default which is all we wanted in the first place.

[Richard]

on my MP comment... just like you can't see them in the pilot list until they come into some range, the craft will load even if you cannot visually see it in the distance... if it is listed in the pilot list, it is loaded...

I don't think it actually loads the model until it is visible; maybe there is a preload check that allows FG to know.

Loading of MP models is controlled in View->Adjust LOD Ranges where there are two AI/MP sliders. These control when the model is loaded.

[wkitty42]

i'm not sure... my understanding is as above... within what? 100 nm is when the pilot shows on the list? plus with my AI/MP settings (see above), 50nm out is where i should start being able to see them or at least their landing lights... in the case of the AI craft and the new beacons and marker lights, i'm anxiously awaiting the time when they also have landing lights available and we can see them at a distance...

i know from KRDU, we can stand outside on an observation platform... we can look west-south-west and see, waaaaay off in the distance, the line of craft headed into Raleigh... we can see them because of their landing lights being on... sometimes the craft turn their landing lights off and then back on... we assume this is under direction from the tower personnel... during the time the lights are off, we might be able to make out the dark spec of the craft with the Mark I eyeballs... if one has binoculars, i'm sure they can see more... in any case, the end of that line of lights is way out past BUZZY... BUZZY is maybe a mile or two south-west from our location... according to Google Earth, we're roughly 40 miles, as the crow flies, from KRDU... that puts us within range of seeing the craft, from the KRDU observation platform when they are 50+ miles out, before they have arrived at BUZZY... when they arrive at BUZZY, they then turn right to roughly heading 050 and start aligning for one of the two RWY05s... from there, it is a straight shot down the glide path to the threshold...

[Hooray]

You can refer to the wiki for details - IIRC, Torsten implemented PagedLOD support, where the size of the object in pixels is used as the heuristic determining whether to load/display the model. One of the newsletters/changelogs may also contain additional info.

[Richard]

i'm not sure... my understanding is as above... within what? 100 nm is when the pilot shows on the list? plus with my AI/MP settings (see above), 50nm out is where i should start being able to see them or at least their landing lights

You can choose to have MP aircraft shown at a particular distance, or when they occupy a certain number of pixels on the screen. This is a recent change (last few years) that Torsten and it does remove the need to load all models once they come within the default 100nm range. Outside the default 100nm range you will see nothing as fgms doesn't even transmit these.

So the model will come onto the mplist when it arrives; but the 3d model loading is controlled by the aforementioned dialog

[wkitty42]

You can refer to the wiki for details - IIRC, Torsten implemented PagedLOD support, where the size of the object in pixels is used as the heuristic determining whether to load/display the model. One of the newsletters/changelogs may also contain additional info.

i used to use 0px or 1px in my AI/MP LOD settings but changed to using meters for more accurate distance knowledge... it was painful to know that a craft was Xnm out but still not able to be seen when it should have been visible... even now i tend to struggle trying to see them when they are further out than a few minutes... some seem to suddenly blink in/out at some preset distance instead of following my sim LOD settings... too bad there's no way to tell the sim to ignore those distance options and use the LOD settings no matter what...

[wkitty42]

Outside the default 100nm range you will see nothing as fgms doesn't even transmit these.

it is my understanding that fgms can transmit ranges further than 100nm... i know that at least one or two of the ATC apps allow for up to 500nm range on their scopes... that wouldn't work if fgms only transmitted 100nm or less...

[Richard]

it is my understanding that fgms can transmit ranges further than 100nm...

Since the MP update in 2017.2 it can indeed bet set; I added this to the MP protocol and fgms implemented it. I was trying to keep the discussion simple. This distance is not considered to be a user setting; it is something that the model should control as appropriate.