kernel-2.6.17-1.2139_FC5 won't sleep

David A. De Graaf dad at
Wed Jun 28 20:01:34 UTC 2006

On Tue, Jun 27, 2006 at 02:33:51PM -0400, Matthew Saltzman wrote:
> On Tue, 27 Jun 2006, David A. De Graaf wrote:
> >>>I haven't accurately measured the comparative rates of battery
> >>>discharge while asleep vs. awake because it takes a long time to do
> >>>the experiment.  I will, though.
> >>>I do have the subjective recollection that when the earlier non-ACPI
> >>>system slept, the battery drain was very, very low.

> >>OK try the following:
> >>	options radeonfb radeon_force_sleep=1
> OK that fix is known to solve the Radeon power-consumption-in-suspend 
> problem.  It looks like there is still something else going on and using 
> the radeonfb driver doesn't fix it.

I've measured the time to discharge two ways using  acpitool -b
1)  The laptop running quiescently, with screensaver operative
2)  The laptop in sleep mode, and manually woken periodically
Both runs used kernel 2.6.16-1.2133_FC5 (because the 2139 version
won't work) and the radeonfb radeon_force_sleep=1 option was used.

Running  screensaver			Sleep mode	
Time		Charge		Time		Charge
10:58:43 AM	100		03:11:34 PM	98.54
11:18:43 AM	83.53		03:12:00 PM	98.51
11:38:43 AM	69.76		04:09:30 PM	74.84
11:58:43 AM	58.1		04:41:39 PM	63.4
12:18:43 PM	46.63		05:00:27 PM	56.62
12:38:43 PM	35.13		05:35:23 PM	44.32
12:58:43 PM	23.72		06:00:25 PM	35.45
01:18:43 PM	12.43		07:00:56 PM	14.28
01:38:43 PM	1.34		07:34:55 PM	0.03
				08:01:13 PM	31.18
Time to discharge:
2h:40m = 2.67h                  4h:24m = 4.40h

That's not very impressive; only 1.65x longer with sleep mode.
I don't think the sleep mode is getting everything turned off that
could be.  The operative /etc/acpi/events/sleep.conf action is
    acpitool -s

Perhaps there's a more effective way to enter sleep mode.
Any suggestions?

I've just tried manually running
    acpitool -S
which suspends to disk and, to my amazement and surprise, it works!
The laptop totally shuts down and can be awakened with the power
button.  It takes somewhat longer, but the power drain is zero.
My amazement is because I don't have a partition set aside for this,
which I thought was necessary.
Apparently it uses the swap space (and that's why one should have a
swap partition as big as RAM, even if you never swap).

Can anyone confirm that?

	David A. De Graaf    DATIX, Inc.    Hendersonville, NC
	dad at

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