----- Original Message -----
Hi,
On Fri, Sep 14, 2018 at 8:53 AM, Christian Fredrik Schaller
<cschalle(a)redhat.com> wrote:
> My take on this is that we want the feature, but not as a 'try to see if it
> works' feature. So my suggestion is as
> follows:
> 1) We disable it by default
> 2) We develop some kind of whitelisting system to allow us to enable this
> on
> systems we know it works (maybe tie it into the whitelisting system Hans
> has
> created for other power saving features?)
> 3) Once we have this is place we can discuss doing a UI to allow people to
> tweak behaviour of this, like they do on MacOS X, but it would be a UI that
> is only visible for people on whitelisted systems to tweak between known
> behaviours, not a 'try to turn this on to potentially break your system'
> UI.
I think this is a good idea, but the problem is, unless my information
is stale, there are
no systems that it works reliably on. The reason is this:
1) hibernate requires a swap partition to work
2) the swap partition needs to be at least as big as available memory
3) the swap partition can't be reserved for just hibernate to use
4) if other things end up using the swap partition then it needs to be
even bigger
5) there's no limit on how much bigger it could conceivably need to be to
work
in all situations
so assuming i'm current and accurate on those 5 points, i don't think
a whilelist
is going to help until we gain a kernel feature that let's us
designate a specific
part of disk that's solely for hibernate to use.
See the first item:
https://wiki.gnome.org/BastienNocera/KernelWishlist
µswsusp is what I've been told would be the best course of action.
For systems that support it, adding native Intel Rapid Start support in the
kernel would also be good, as it uses a separate partition to save the RAM:
https://gist.github.com/hadess/6968197
Though Intel dropped support for the feature now, and we need this to be
supported at the kernel level for systemd to add support for it...