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psylichon · 11-12-2007, 05:59 PM

Originally Posted by mobilehavoc

Most mobile ARM CPUs use some form of cpu scaling to make the most out of battery life - which is probably what you're seeing. I always thought the supposed Samsung ARM CPU in the iPhone was rated for 600mhz too.

If you think about it, it doesn't make sense to run the CPU at full speed unless there's sufficient load.

Using VT-Term100 or SSH you can run 'top' on your iPhone which gives you a live sys monitor (auto refresh). Using SSH you can leave this open and then run stuff on the iPhone. You rarely see CPU % go higher than 60% for more than a second. This leads to believe 400mhz is the battery saving frequency and it only runs at 600mhz when needed.

Good obvservation! I'd heard 600+ mhz as well, so this likely means that maybe Apple decided to trade off a bit in battery life to up the "standard operating performance level" of the Iphone. Or perhaps the new firmware introduced some other battery-saving measures, so they celebrated by giving us some more speed? Either way, it's pretty cool that they can do that with software alone, right?

Personally, I love the processing overhead on the Iphone... I think they really nailed it. It never really seems to slow down, even under full load.

11-12-2007, 05:59 PM	#5 (permalink)
psylichon Super Moderator Join Date: Oct 2007 Location: Philly Posts: 10,789 Thanks: 442 Thanked 984 Times in 683 Posts	Originally Posted by mobilehavoc Most mobile ARM CPUs use some form of cpu scaling to make the most out of battery life - which is probably what you're seeing. I always thought the supposed Samsung ARM CPU in the iPhone was rated for 600mhz too. If you think about it, it doesn't make sense to run the CPU at full speed unless there's sufficient load. Using VT-Term100 or SSH you can run 'top' on your iPhone which gives you a live sys monitor (auto refresh). Using SSH you can leave this open and then run stuff on the iPhone. You rarely see CPU % go higher than 60% for more than a second. This leads to believe 400mhz is the battery saving frequency and it only runs at 600mhz when needed. Good obvservation! I'd heard 600+ mhz as well, so this likely means that maybe Apple decided to trade off a bit in battery life to up the "standard operating performance level" of the Iphone. Or perhaps the new firmware introduced some other battery-saving measures, so they celebrated by giving us some more speed? Either way, it's pretty cool that they can do that with software alone, right? Personally, I love the processing overhead on the Iphone... I think they really nailed it. It never really seems to slow down, even under full load.