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Tips for better frame rates Pt #1

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.

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.

***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!

A Few Settings Tricks to Try

For those who cannot wait to try to get X-Plane 10 to run fast, a few tips on how to ‘break down’ where a bottleneck might be:

• Run with clouds vs. clear skies.  The clouds chew fill rate.  Are clouds the issue?
• Turn down visibility – X-Plane 10 will run at 100 nm but some machines will die with this.  Does a low visibility help?
• Turn off the AI planes.  Any better?  They take draw time when on screen and cores.
• Turn down texture res if you haven’t already.  (Well, most people try that by default.)  Start with low settings and work your way up.
• Try areas away from KSEA.  Compare down-town to rural, and different airports.
• If you have an nvidia card before the 400 series, try running with –no_instancing from the command-line.  This can particularly help Mac users.

In most cases there is only one setting killing your framerate – find it, fix it, and things get a lot better…fix it and you’ll find those other settings you turned down can go up at least a bit.

The gotchas in v10 are definitely different from v9.  Shadows can kill your fps in a huge way – I’ll be spending a bunch of time tuning them to look better and kill fps less.  Turn water reflections down if you don’t need them – the “advanced” setting is frankly a bit pointless.  Turn off full screen anti-aliasing if you are going to run in HDR mode, then restart the sim.

Rendering Settings and FPS: Don’t Panic

I am still trying to dig out my in-box this morning, but Chris tells me that there is a lot of concern over X-Plane 10’s framerate.  For now I can only offer one bit of advice:

Don’t panic.

I have no doubt that many users are seeing terrible fps with version 10.  But I think that we’re going to get this sorted out over the next few weeks and the end result will be really good.

How can I think that when so many users are seeing poor performance?  Here’s why…

• With X-Plane 9, four years after its debut, you still can’t run X-Plane 9 at extreme objects on a modern computer.
• With X-Plane 10, all of 1 day old, with very little performance ,i can run at extreme objects on my core i5 and get > 20 fps in the demo area.

In other words, the hardware usage of v9 was never properly “fit” to the capabilities of a modern desktop.  By comparison, version 10 is at least on the right curve, and we know how to tune for performance.

Please bear with me for a few days: the current state of chaos in our server download farm is a high priority right now, as are a few serious bugs.  So if you send me a list of your hardware specs, settings, and some numbers, I cannot help you.

When I do have time to look at performance (hopefully real soon) here’s how we will do it:

• I will post some standard fps-test command lines that you and other users can try.
• You can send me back the log.

One I have that data, controlled for all rendering settings, across a variety of hardware, then we’ll be able to understand performance and fix engine bugs and provide work-arounds.

X-Plane 10 is only fast if it hits the fast path through the driver every time it needs to; there are all sorts of little things that can go wrong that can kill fps that are not an indication that long-term the sim will suck.  We have worked through nasty performance issues before and we will again!  It took two months to kill off the very last driver problem in X-Plane 9.0 – I certainly hope it won’t take that long to get the vast majority of users running well in version 10.  But I do believe that fps problems we see now may be as much a case of driver vs. engine quirks than a fundamental performance gap.