Re: [Bug 75101] New: [bisected] s2disk / hibernate blocks on "Saving 506031 image data pages () ..."

[matheus <matheusfillipeag@gmail.com>]

> So you got hibernate working now with pm-utils*and*  the prop. Nvidia
> drivers. That's good - although a bit contrary to what you said in
> Comment 29:
>
I was told so, long time ago struggling to get nvidia prop to resume 
from hibernation, I found out that uswsusp was better for it (googling 
or on irc), and it indeed worked better, or with less effort at least, 
back  then.  I made that comment thinking this was true but I just 
proved myself wrong...

> till puzzles me is that while others are having problems,
> suspend-utils/uswsusp work for me almost 100 % of the time, except for a
> few extreme test-cases in the past. You also said that it worked
> "flawlessly" for yo

Yes! It worked pretty good on version 18.04.1 of ubuntu with kernel 
4.15.0-42 and 41 using uswsusp. There was a long problem with nvidia 
props that wouldn't let the system resume, but this was fixed when I 
upgraded to the latest version of the 415 nvidia driver. I kept like one 
month just hibernating to switch to windows and coming back to the 
restored snapshot of linux.  You can check my apt history here: 
https://launchpadlibrarian.net/415602746/aptHistory.log. At the 
Start-Date: 2019-02-02 15:40:45, I'm 100% sure it was perfect. I am 100% 
sure that it wasn't already working anymore having the s2disk freeze 
issue at Start-Date: 2019-03-05 10:38:4.

uswsusp also worked fine on ubuntu 16.04, but I dont remember the kernel 
versions. Now I'm currently with the nvidia 418.56, ubuntu 18.04.2, 
kernel 4.18.0-17-generic and hibernation with pm-utils works. I haven't 
found any major problem with it besides failing to suspend to ram 
yesterday, which  I don't know if is related to it or not, but today I 
tested it after and before hibernation and seems to be ok.

> So I'm wondering whether used-up swap space might play a role in this
> matter, too. At least for the cases that I've seen on my system, I can't
> rule this out. And when I look at the screenshot you provided in Comment
> 27 (https://launchpadlibrarian.net/417327528/i915.jpg), sparse
> swap-space could have been a factor in that case as well. Because
> roughly 3.5 GB free swap-space doesn't seem much for a 16-GB-RAM box.

On my many tests with uswsusp and a 16gb swap partition and 16 gb of 
ram, I noticed that it would be less likely to fail when less than 
something about 2 gb of ram, like just after boot up, it would though 
after the 3rd or 4th followed hibernation cycle. If after the boot up I 
allocate more than that value if would be much more likely to happen 
like always on the 2nd attempt, and if more than around 6gb would fail 
on the first attempt.

Those aren't sure values, sometimes it failed regardless of ram usage, 
specially on my latest tests. also once it hibernated with more than 
11gb ram usage and failed on the second attempt. So this is all 
happening pretty randomly. What I described above is just most of the 
cases and maybe this is just random anyway.