Getting Framerate Performance on iPhone

I've just come off the PSP where performance testing was easy. You just turned off 'vsync' and printed out the frameratem, then change something and see whether the frame rate goes up or down...

Is there any way to do the same thing on the iPhone? How do you turn vsync off? The Instruments tool 开发者_JS百科is next to useless. Its chief problem being that it running it adversely affects the performance of the app! Also, the frame rate it reports is extremely sporadic.

I don't want any fancy tool that reports call trees and time spent in each function. I just want an unrestricted frame rate and some way to see what it is. Is there a high precision counter that you can use on the iPhone? Something like QueryPerformanceCounter in windows?

Also, is there anyway for you to somehow KILL backround processes so you know they can't effect the performance, perhaps solving the sporatic frame rate problem?

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Profile your app with Instruments and use the Core Animation instrument. It gives a frame rate.

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You're taking the try-something-and-measure approach. Very indirect. It's easy to tell exactly what is taking the time; it doesn't depend on what else is going on and doesn't require learning a new tool. All you need is a debugger that you can interrupt.

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You can't kill background processes on the iPhone. That would make it possible for a buggy or malicious app to interfere with the phone function and the needs of all other functions on the iPhone are subordinated to the phone.

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Try QuartzDebug or OpenGL Profiler.

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Use instruments to get the frame rate.

To do this, run profile on your app (click and hold on the run button in xcode and choose profile). Make sure you are running your app on device. Choose openGL ES analysis. Look at the data display under core animation frames per second.

You want to aim for 60fps.