On Wed, 2004-12-29 at 08:48 -1000, Amy M wrote:
> All things considered, this fedora-list has become perhaps one of the
> best forums to learn Linux. Our sincere thanks to those who are
> gracious enough to donate their time answering questions that sometimes
> may seem ridiculous.
>
> My question now is: From what I have read, it appears that if I want to
> do suspend to ram, I have to forgo acpi and use apm. Performance-wise,
> would anyone care to comment on the pros and cons of acpi vis-a-vis
> apm? Thanks again.
Hi Amy,
I can only relate my FC kernel-2.6 experiences for one laptop, a
ThinkPad A22p (PIII-900) and they are:
- with very recent kernels (eg. 2.6.9-1.681_FC3) both APM
and ACPI suspend-to-RAM work
- with both I often need to unload and then re-load the
sound kernel modules
- APM:
- uses *very* little power when suspended to RAM (lasts
for many days starting from a full charge)
- can occasionally have problems with pcmcia (even when
all cards are removed) so I usually use:
"/etc/init.d/pcmcia stop ; apm -s"
and then restart pcmcia after wake-up with:
"/etc/init.d/pcmcia start"
- results in lockups about once every 40--50 suspend-
resume cycles
- ACPI:
- has no apparent problems with pcmcia
- experienced no lockups (in about ~60 cycles)
- uses a *LOT* (perhaps as much as 10X) more battery
power while suspended to RAM
- suspends and resumes very quickly
- routinely gives a kernel error on wakeup saying
something about interruptable_sleep() but they seem
to be harmless
Having done many hundreds of suspend-resume cycles using both APM and
ACPI, I've decided to stick with APM to reduce the battery usage.
Ed
--
Edward H. Hill III, PhD
office: MIT Dept. of EAPS; Rm 54-1424; 77 Massachusetts Ave.
Cambridge, MA 02139-4307
emails: eh3@xxxxxxx ed@xxxxxxx
URLs: http://web.mit.edu/eh3/ http://eh3.com/
phone: 617-253-0098
fax: 617-253-4464
