nice would it be feasible to also compress kernel dumps once the compression logic is in place for hibernation?
On Wed, Jul 11, 2012 at 11:41 AM, Mike Larkin <mlar...@azathoth.net> wrote: > Hibernate support (suspend-to-disk) will be shortly enabled for i386 + wd > machines. > > Some FAQs, before I commit the change to turn it on: > > 1. If you have anything other than i386 + wd, it won't work. Don't report it. > Other archs + disk types are being worked on now that i386 + wd is working. > This means, *FOR NOW*, it works on combinations like this: > > wd0 at pciide0 channel 0 drive 0: <INTEL SSDSA2MH160G1GC> > > .. NOT this: > > ahci0 at pci0 dev 31 function 2 "Intel 82801I AHCI" rev 0x03: msi, AHCI 1.2 > scsibus0 at ahci0: 32 targets > sd0 at scsibus0 targ 0 lun 0: <ATA, M4-CT512M4SSD2, 0009> SCSI3 0/direct > > > > 2. Hibernate writes to swap (at the end of your swap). If you have too small > a swap, it won't work, or if there are swap pages in use at the end of your > swap that overlap with what we want. You need at least "size of mem + 64MB" > of swap at the end of swap, free, at the time of hibernate. > > 3. We do *not* do encryption of the hibernated image, even if you have turned > on encrypted swap. > > 4. If you change your memory size/layout or change your kernel, we will detect > this and abort any hibernate resumes. The resume will be a normal boot then. > > 5. It will be very slow for the time being - this is a known problem that > I am working on fixing, but for now, we will wastefully write all memory, > even pages that are not in use. This will be fixed, so please don't report > that "it's slow". On my machine with 1.5GB ram, it takes a few minutes to > write > everything out, and about 30s to read it back in on resume. > > 6. Hibernate can be triggered via 'ZZZ' in -current (capital 'Z's for > hibernate, > lowercase 'z' for suspend). > > 7. Right now, there is no unwind support for errors. This means that just > about every failure case will result in a panic or reboot. This too is being > worked on. > > If you have a supported (see #1) configuration and want to test it, let us > know if it works (or doesn't). There won't be a diff posted here, it will just > get enabled, probably sometime later tonight or tomorrow. > > -ml
