How can I investigate the cause of total hang? Is there some information that I should pay attention to in order to get some hint?

[Drew Einhorn]

On Sat, Jul 4, 2020 at 7:28 AM Karl Auer <kauer at biplane.com.au> wrote:

> On Sat, 2020-07-04 at 06:43 -0600, Drew Einhorn wrote:
> > I'm using my computer.
> > I walk away come back later.
> > It is now unresponsive
>
> Coming in late, so forgive me if this has been said.
>
> Is the "unresponsive system" actually asleep when you return to it?
> Does your system show some clear indication when it is asleep (or
> hibernating)? If NOT, try disabling all automatic sleeping hibernating
> and blanking, and see whether the system still becomes unresponsive
> after you walk away for a while. You could also inspect the sleep/blank
> settings and just wait that long to see if it happens "on time" :-)


I don't know to tell whether it is sleeping, hibernating, or blanking.
The screen is dark.
Ctrl-Alt-Fn works as expected for n = 2..7

Ctrl-Alt-F7 lights up the screen in graphics mode.
With a message indicating the screen is locked and in a few seconds an
unlock dialog will begin.
In a few seconds, the screen goes dark again.
I'm assuming something is going wrong with the unlock dialog.

Not coming back from sleep and not coming back from blanking are (or at
> least used to be) relatively common problems, though sadly not with
> common solutions. If you can show conclusively that the issue is
> related to sleeping, hibernating or blanking, you will at least have a
> better idea where to look, and also a good workaround (disabling them).
>
> Did this problem develop recently or has it always been there on this
> computer?
>

I recently installed the OS on this system.
I'm not sure whether it worked properly for a short while before the
problem started.
If I don't resolve this soon, I will reinstall and hope it goes away.


> You *may* be able to restore graphics without actually restarting the
> computer, by just restarting the display manager. When logged in, look
> in the process list for something with a name like "gdm" or "lightdm"
> etc. Then try restarting that process. For example, if you find gdm3,
> you might restart it with "systemctl restart gdm3". You could also try
> just killing the process, as it will generally be restarted
> automatically, but I have not tried that myself


I see that lightdm proccesses are runnning.
"systemctl restart lightdm" gets graphics restored.

That's a big step forward.


>
>
Regards, K.
>
> --
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-- 
Drew Einhorn
Where are we going?
And, why am I in this handbasket?
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