Austin, Ben and I are still working on cleaning out the remainder of Ultra-High priority bugs right now which essentially consist of crashes or other things that impact large groups of people. Only once these types of problems are taken care of will we be able to start looking into figuring out what can be optimized in the sim.
Many of you are getting really decent performance. Many of you are getting “ok” performance and others are getting really poor performance. This is not a surprise because there is a huge spectrum of hardware out there. Moving forward, we have some tools at our disposal that we can use to collect some data see what’s impacting performance the most. Then we can optimize it. Then we can see what the second biggest problem is, and then optimize that….and around and around we go.
In my opinion, one major contributor to performance loss right now is having your settings wrong. X-Plane allows you to configure a LOT of settings to get optimal performance. We’ve given you more than enough rope to hang yourself with, and many of you are doing just that. X-Plane’s rendering engine is very flexible. It has to be because it has to run on a huge spectrum of hardware. Like any large system, it needs to be tuned properly for its intended use. Ben’s already told you that you need to hit rock bottom to tune X-Plane properly. What that means is that you need a baseline. Think of how you tune a guitar or any instrument for that matter. You need a reference pitch such as a tuning fork. You match one string up perfectly to that pitch and then you adjust ONE string at a time until it’s in tune with the previous string. Imagine trying to tune a guitar without a reference pitch. You would have no idea whether you were making progress or not!
The “tuning fork” of X-Plane is starting from zero. This is your reference. Turn off EVERYTHING. Turn of AI aircraft, set your clouds to clear, set your visibility to something reasonable like 20-30SM, turn off rain and storms. Go to your Rendering Options and set EVERYTHING as low as it will go. If you run X-Plane in fullscreen mode, turn down your resolution. If you run X-Plane as a window, reduce the size of the window. The item that says “Framerate-lock to monitor” should be set to “Do Not Lock” (more on this in a moment). Take a look at what kind of framerate you get in the sim. Don’t just sit on the runway, fly around, take note of the range that you see. Also, see what you’re system’s doing as well as you can. Take a note of CPU usage, Memory Usage (mainly how much is left to be used), and GPU usage if you have a fancy driver that lets you see this information. At this point, you should have a rough guess as to what your weakest link is. If your CPU is almost maxed out right now, it’s going to be your limiting piece of hardware. If your almost out of memory, that will be your limit etc.(A quick detour on CPU cores…more is better-ish…to a point. 9 women can get together and do 9 different tasks in 1/9th of the amount of time it would take 1 woman, but 9 women cannot have a baby in 1 month! The point is, if X-Plane has multiple tasks going on (like AI traffic, scenery pre-loading etc), then multiple cores helps get the tasks done quicker. But if there’s only one task going on (like rendering), your other cores will NOT help you do it any faster.)
Back to tuning…Start with Rendering Options. Now start turning things up ONE setting at a time. Start with things that are most important to you. Each time you change something, go back to the sim and see how it impacted you. Take note of your hardware utilization again. Has CPU changed much? Has memory changed much? Don’t be fooled by large jumps in FPS. Remember, going from 100fps to 90fps is a difference of 10fps (“wow” you’re thinking)…but that’s only 10%! That same 10% reduction at 20fps would bring you down to 18fps. You should care about the PERCENTAGE change, not the FPS change. If you notice that one setting in particular causes your framerate to lose a huge percentage, then you’ve probably figured out what the weakest part of your particular hardware is. This is the setting that you’ll either have to live without or the one you’ll have to be VERY careful about touching. If this setting is important to you, perhaps there is something else that you can sacrifice to get some performance back for this setting. Or if you’re able to upgrade your hardware, that’s the thing that you should invest in.
At some point, hopefully you’ve found yourself with a configuration that you like. Again, note your average FPS in various situations. NOW you can go back and set the weather how you like it. Turn the clouds up, turn the visibility up if you want but be careful. Visibility can be a huge factor in performance. The farther you can see, the more things the system has to draw. I would not recommend going over 50SM unless you find yourself with a ton of performance left over. Now you can turn on the number of AI planes that you like flying around with. You may have to go back and retune some things to get the system balanced with the new weather and AI. Make SMALL incremental changes. You don’t want to de-tune it severely. When everything’s balanced, now go back into Rendering Options and note at the very bottom, it will tell you how much VRAM is being used. Turn the Texture Resolution up until the VRAM usage gets near the amount of VRAM you have on your GPU. Then fly around and test it. You should NOT notice any difference in performance. If you do, go back and turn your Texture resolution down a notch and try again. Your goal is to get your texture resolution as high as you can without impacting performance or going over your VRAM limit.
Lastly, a note on VSync. I told you earlier that the “Framerate-Lock to Monitor” setting should ALWAYS be on “Do Not Lock”. This is a tiny white lie. If you’re an advanced user, if you know what VSync is, if you know how it works and if you have enough performance to spare and you want to stop scene tearing, go ahead and turn it on. Even then, don’t turn it on until you are done tuning framerate, because VSync will obscure changes in fps, making it impossible to tell what effect a rendering setting has on your hardware. If you don’t know what it is or what problem it’s meant to solve…please leave it off and forget it exists. It will NOT improve your performance. If you’re like me and just want to learn about it anyway, read this but leave the setting off anyway.
|AI Aircraft||CPU/VRAM/Bus Bandwidth|
|Objects||Bus Bandwidth (CPU on old cards)|
|Screen Resolution / Window Size||GPU (usage proportional to resolution)|
|Shadows||Bus Bandwidth (this amplifies all other bus bandwidth use a lot!)|
***EDIT*** I didn’t want to have to do this but I’m going to be more heavy handed with the comment moderation because inevitably, the comments end up getting WAY off topic. Feel free to ask questions or post comments directly related to the topic but this is not the forum for other discussions. I am also not going to be providing one-on-one tuning at this time so please do not post your specs unless asked. We have not begun diving into performance issues yet. The purpose of this post is to educate you on how to setup your own system in the most optimal way possible right now. Thank you for your understanding!