On Wed, Aug 15, 2001 at 01:17:31PM +0100, Vivek wrote: > > > Slight correction - you need the hibernate partition to enter hibernate > > > mode > > > - you should be ablt to suspend just fine without it. > > > > I may be confused here - but wouldn't that be standby mode? > > No - standby and suspend are distinct: In standby mode the machine is till > on, the kernel is still ticking away, but some (possibly only fuzzily > defined) power saving things, like spinning the HD down, turning off the > monitor, clocking the CPU down, etc have happened. > > In suspend mode, the machine is almost off - just enough power is consumed > to keep the memory alive, and pretty much everything else is off. [There may > be > a trickle of power to things like the NIC, so wake-on-lan type things can > happen]. > > In hibernate mode, the memory+videomem [as you say] is flushed to permanent > storage, and not even the memory is powered - The BIOS knows how to read the > state back from storage into memory, and the kernel knows how to come back > to life from there. > > You may have been confused by the 'swsusp' project, which achieves something > similar to hibernation. I think it works by having a kernel that can boot > very quickly with a 'memory-image' file: The kernel flushes data to disk and > shuts down - then when it comes back, it detects the file, and instead of > going through the normal boot process, slurps the file into memory and takes > a running jump back to wherever it was when you shut down. > > Same effect as hibernation, but no BIOS/APM/ACPI support is required. > > Standby mode is, AFAIK, not often used, at least not explicitly by the user, > and has little impact on the user anyway, since the moment they start > prodding the machine, it should come back to 'full on' mode. > > I use suspend a lot myself - my thinkpad will last 5~7 days while suspended, > and I generally turn it off if it's going to be out for longer. > > Hibernate doesn't work for me - I ran the IBM utility to create a partition > for it, but I just get a beep and a 'system is invalid' message if I try to > suspend. Not sure why. It'd be nice if it worked, but I don't need it so > it's Ok - I may try out swsusp later.
That's a lot of interesting information, especially about swsusp, which I wasn't aware of. If you suspend to RAM, energy use probably depends on the amount you have. Do you think that extending your RAM shortens suspend time? Thank you! Rolf
