PilotEdge Forums

I've been having a reoccurring issue with X-Plane (v10) where, with no identifiable cause, my FPS would drop to 1. Even saw 0.15 at one point. Now, this is textbook behavior for VRAM exhaustion, but with a 1080, I thought that was unlikely, especially when I looked in Rendering Settings and saw X-Plane reporting as using "2823.11 meg" of VRAM. Since a 1080 has 8192MB available, clearly that wasn't the problem, so I spent time troubleshooting other things, disabled threaded optimization, blah blah.

But as it turns out, X-Plane is a complete and total liar about VRAM usage! It happened again on my stream last night, so I did some more research, and found other people running into severe FPS drops that recommended using GPU-Z to monitor VRAM usage. Turns out that, when sitting on the ground at one of the MisterX airports, my VRAM usage reported by X-Plane was 4800mb, but GPU-Z reported 7890mb in use! So, enough that any random textures or distant airport scenery loading in would push me over the limit.

I've now reconfigured to lower max texture size to 'Very high' instead of 'Extreme', and am comfortably under the limit. The good news is the sim doesn't look too different, plus I had experimented with world2xp but found that it murdered my FPS - now that I have more VRAM available, I can have that installed and the sim looks better than before.

Nice catch. I think the "reported VRAM" usage in XP is from the texture settings. There's other factors like the raw Windows overhead plus any other loads on the card like encoding for the stream.

Thoughts?

Tim, is the frame rate drop only when connected to PE, or is it all the time?

stevekirks wrote:Nice catch. I think the "reported VRAM" usage in XP is from the texture settings. There's other factors like the raw Windows overhead plus any other loads on the card like encoding for the stream.

Yeah, a Redditor also suggested it may have been a leak/bug of some kind.

rtataryn wrote:Tim, is the frame rate drop only when connected to PE, or is it all the time?

Uncertain, I don't think I ever encountered it when disconnected, but I don't think I disconnected while it was occurring either.

I had always the same impression but never
proofed it. Just stopped trusting the displayed
value and switched to external tools like
Afterburner or GPU-Z.
Thanks for the confirmation!

Tim,

If the frame rates return to normal after disconnecting from PE, and you use an iPad with traffic, it may be the IP address in the VSProTrafficRelay.ini file doesn't match the iPad IP address. That will cause significant frame rate drops like you've described.

Not using an iPad with the sim at the moment, but good to keep in mind.