Return to the archive index

Re: Microdrive on PCM-5822

From: Chris Kalos <>
Date: Sat, 2 Dec 2000 23:21:34 -0500 (EST)

	You're confusing your suspend methods.  There's Suspend to RAM,
which just puts everything is a low-power mode, giving just enough juice
to refresh the RAM, and little else.  The CPU is still running, but it's
certainly not capable of doing anything in terms of real work.
	Then there's our good friend, Mr. Suspend to Disk.  This is the
holy grail of battery-bailing goodness.  It's also called "Hibernate mode"
and "suspend mode."  Linux APM has been capable of this for a while (dare
I say years?), just not as reliably as apm -S / suspend to RAM / standby
mode.
	You need an APM capable BIOS for all these tricks, true, and
usually the end of the hard drive isolated for writing purposes (ask IBM
about their *BSD support and how they screwed us with their choice of
partition IDs), but either a legit hibernate partition *or* a large enough
swap will usually work.
	The cool part nowadays, though, is that even desktop machines can
pull this off.  I use this when I have to move my workstation at the
office, or just to save power, because the boot time is an obscene 20
seconds in Win2k (I said workstation, so yes, it's at my job).  I'd
imagine it's the same for Linux, perhaps better depending on what you left
running.
	As a rule, though, if your system has stored state to disk, you
can remove the hard drive, replace the motherboard with the exact same
model, and bring it back up cleanly.  I've done so when sending laptops
in for repair.
	Ain't technology great? :-)

CK
Long time lurker... and yes, once I start posting, it doesn't stop :-P

> Well, first, that's done in the bios, not in the os.  Second, it generally
> dumps the memory to disk, and powers down, but not all the way down --
> it's still actually on and drawing power, just not very much.  With this,
> you can power all the way down, remove batteries, bios batteries, swap
> hardware, anything.  Granted, you need to have the same hardware/bios
> configuration when you come back up, but that's the only limitation.  As
> at least some device drivers are explicitly unloaded and reloaded, you
> could even (theoretically) do something like add non-hotswappable scsi
> disk (in practice, this might not work, but...).
> 
> /P.
> 

--
Subscription/unsubscription/info requests: send e-mail with subject of
"subscribe", "unsubscribe", or "info" to 
Wear-Hard Mailing List Archive (searchable): http://wearables.blu.org
please, Please, *PLEASE* don't subscribe through a forward/false domain

+Previous Message in Thread | Next Message in Thread

From Wear-Hard Mailing list Archive (WH)
Maintained by R. Paul McCarty

Archive created with babymail