Sprite Kit touchesbegan: delay/lag

问题

-(void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {

NSLog(@"touch");
...
}

I have a really simple problem that I can't find any answers to. Most of the time, when I tap the screen, the nslog executes immediately. However, about 1 in 5 times, there is a half second pause before the message displays. I'm making a game and I need the touchesbegan to execute immediately. Can anyone tell me what I'm doing wrong? BTW, the framerate is a mostly constant 60 fps.

来源：https://stackoverflow.com/questions/23047732/sprite-kit-touchesbegan-delay-lag