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So I've switched from NSTimer to CADisplayLink and I'm still seeing unexpected variation in my frame counter - it fluctuates between 59-60fps, even when I'm not rendering much.

Has anyone else seen this? Is this an expected variation in iOS? Or should I look more closely at my game loop?

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up vote 6 down vote accepted

From my experience this is normal behavior. The measured time can change slightly and if 59.99 FPS are calculated and you output that with just 2 digits, it's going to show 59.

Don't worry about fluctuations of one frame.

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Ok - I was outputting XX.XX digits but it flickers too quick for me to see, and I didn't bother tracking min/max value. If other people see this then I'm happy. – Justicle Feb 22 '11 at 23:05

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