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The only hitch in the procedure that is even sorta the fault of Linux is that I don't know how to get it so that the computer will hibernate/resume.

Check out swsusp.

swsusp stores the data in the swap partition.
Suspend2 can write it to a file instead.
See http://www.suspend2.net/features

I use Suspend2 on my laptop for conventional hibernation. It's possible to keep old images and choose an image on bootup to achieve what you describe, but there's at least one catch with mounted filesystems. If you have filesystems mounted at hibernation (which is usually the case), you cannot change them until you resume the OS. So if you boot with an old image that assumes some old disk contents, you will corrupt disks.

So, I think what you want is to save the image before anything is mounted writable, sometime early in the init process. I believe you could use suspend2 for this with only userspace modifications.

well, try installting a year 2000 distribution on the stated hardware... works pretty fast doesn't it?

Boot time again, try to compare hybernation not boottime. http://www.suspend2.net/ for Linux...

I mean: apples and oranges anyone?

Dual booting is unpractical - You have to stop everything on Mac OS (Linux, BSD, whatever) to get into Windows and vice versa.

Not quite true.

If you're still in good terms with Linux, you might want to try Software suspend 2, which is an ACPI-independent way of hibernating to the hard drive. It's working great for me, as I can't get ACPI suspend to work either.

While the vanilla version works basically, Suspend2 is a more complete implementation. I use it on my laptop regularly.

You can use something simmilar to this now... just use software suspend 2 and save to a filesystem on a flash card in your pcmcia slot.

I've been using the latest 2.6 kernel, patched with Gentoo and Suspend2 patches. I started with 2.6.9, and it had some ACPI problems, but once I upgraded my BIOS to the latest version and upgraded the kernel to 2.6.10, everything worked well. Other than those specific ACPI issues, I've had no general stability problems. Everything works well.

I used to run Slackware, and I have to say that when I upgraded it from a 2.4 kernel to 2.6, the system did perform better. I think that if people just upgrade cautiously, it's fine to have the current kernel in development. Frankly, I appreciate the increases in responsiveness that the newer kernels have, and I like seeing cool new features appear in each kernel version. Why, just this version, they added support for my laptop's temperature sensor chip, which gave me access to the motherboard sensor in addition to the CPU one which is accessible via ACPI.

I don't know what all the fuss is about, but 2.6 has been great for me.

Meh.. Thats nothing, my Gentoo laptop (Centrino based) has been up for 68days 4minues now. And well suspend works, since i have to suspend it when i drive home from work, the battery is dead ;)

http://www.suspend2.net/

FWIW, if you really want hibernation for Linux, here is the website for Software Suspend, a Linux kernel patch that adds hibernation.

So, somebody already took someone up on that challenge, and took care of it ;-)

Overall, Linux on laptops for power management is at the mercy of the laptop's ACPI implementation, the DSDT tables in particular. However, broken DSDT tables are fixable, thankfully this need not be done by each end user, and could easily be automated by a distro install.

The other sticking point is generally hardware suspend/resume, laptops vary wildly in the quality of their implementation of this. Again, if you have a lemon of a laptop, there's still Software Suspend 2, which most have good success with.

Overall, Linux is ready for most laptops, but it's great to see major vendors putting the polish on for their laptops.

for Linux users

I suggest that you either fiddle with ACPI's various sleep states, or try out software suspend. The fact remains that a computer + an operating system + the dozen or so utilities/services you want started combine to make a complex system, and startup times are not likely to get better any time soon. Reducing startup time piecemeal sounds like a Sisyphean task; if leaving the machine on 24x7 is not an option, then suspend-to-disk and the like (as per above) are nice ways to sidestep the problem.

Linux has had hibernation for a long time.
It is included in the main kernel, and I use it every day. Works flawlessly.

http://www.suspend2.net/
Has patches to enable Software Suspend 2. It works wery well on most rigs.

My laptop's Linux takes about 30 seconds to boot up, counting from the bootloader, when resuming from a suspend. This could be tuned a LOT, though -- if I forced it to clean out more memory and write fewer caches, and repeated this on my desktop (which takes 30 seconds for a normal boot, so it'd be much faster from suspend), I might get 15 seconds.

Maybe that's cheating. My desktop linux takes about a minute, including time spent launching an X and a couple of needed programs.

But seriously, people, this is really just problem of bootscripts and choice of desktop. That means that I can make my OS boot in 30 seconds merely by switching to a lightweight window manager, doing a little bash programming, and cleaning out the init scripts I don't need.