Speedy OLPC Suspend/Resume



How fast can you fall asleep and then wake up again? If you are human, this is a good hour, but if you are a computer, how long do you think it should take?

Whatever you just guessed, I am sure it's longer than 10 milliseconds, the speed of a iPAQ handheld running Linux. Why does this matter? As Jim Gettys explains:

The OLPC machine bears some good resemblance to the iPAQ: flash for main storage, integrated graphics, and the like. On our hardware, Mitch [Bradley] measured 25 milliseconds, using LinuxBIOS as the BIOS on the machine.

If Linux on the Geode can be made to resume as fast as an iPAQ (and it is a considerably faster processor), we should be able to suspend to RAM and resume so fast that you won’t be able to observe it under most circumstances, as we might get to the 30-35 millisecond range, which is at the limits of human perception.

By powering down and back up the 2B1 Children's Machine laptop, OLPC hopes to keep its power consumption below the 2 Watt mark, an impressively efficient goal. At 2 Watts, a string power generator might actually work.

That is if Jim Gettys and OLPC can eliminate more wasteful processes. How is this one for an odd wasteful process throwback to the days of PS/2 peripherals:

"the [Linux] kernel waking up 20 times/second just to see if PS/2 devices had been hotplugged on 8042 devices (the laptop I type this on, and the OLPC machine, use PS/2 internally but have no external PS/2 connectors, so waking up 20 times a second to see if something has been plugged in that can’t be plugged in seems a bit pointless.)"
So much on a modern commercial laptop seems pointless and every pointless activity wastes precious battery life. I really do hope that we see OLPC's hardware and software breakthroughs trickling up to high-end portable computers soon - if just for the faster suspend/resume

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