Re: suspend2 merge [was Re: [RFC] Fix Device Power Management States]

[Pavel Machek <pavel@suse.cz>]

Hi!

> > I feared big problems with highmem support, but surprisingly, trivial
> > support thats in current code does not cause problems for
> > people. People seem to like pmdisk+swsusp, too...
> 
> That will be because you're eating most of the memory anyway; there's
> not problem finding enough memory to copy the Highmem too. I guess that
> once we start seeing people trying to suspend 2GB to disk or you try to
> eat less memory, Highmem will become more of a pain.

Yes, I know. I was just pleased that people do not complain as much as
I expected them to.

> > Now, people like suspend2 even more, and for good reasons: it is
> > extremely fast, it provides nice feedback and its refrigerator is
> > superior.
> > 
> > I also realized that suspend2 is fundamentally more complex than
> > swsusp: it introduces additional time period where page cache must not
> > be touched. I did not realize this sooner.
> 
> Sorry. I said it in so many ways! It's not really an issue though;
> processes are stopped and suspend's own I/O doesn't touch page
> cache.

Yes, I know it should work, it is just more things that need to be
verified.

> > Now, there are some parts of swsusp that are not quite okay. One of
> > them is refrigerator -- it fails (in non-critical way but still) in
> > some cases where it should not fail. suspend2 seems to have this
> > solved, and I'd like to merge its refrigerator.
> 
> I'll submit a patch. I need to look at how you use the refrigerator
> first. I refrigerate processes prior to resuming as well, and might need
> to adjust things if you don't do that. I also need to check it will work
> okay with S3.

Actually, we are not stopping processes prior to resuming, but I'd
call it a bug to be fixed.
								Pavel
-- 
People were complaining that M$ turns users into beta-testers...
...jr ghea gurz vagb qrirybcref, naq gurl frrz gb yvxr vg gung jnl!