"Close the app to avoid disruptions" for a closed app

popey · March 10, 2023, 3:58pm

Periodically I’m getting this notification.

I can reproduce this by simply running snap refresh. There is indeed an update pending:

alan@ziggy:~$ snap refresh --list
Name       Version  Rev   Size  Publisher   Notes
snapcraft  7.3.1    8931  66MB  canonical✓  classic

snapcraft isn’t running.

alan@ziggy:~$ ps aux | grep snapcraft
alan      435432  0.0  0.0   9076  2304 pts/5    S+   15:57   0:00 grep --color=auto snapcraft

What gives?

ogra · March 10, 2023, 4:41pm

a plain snap refresh (without --list) should actually print out the PID of the blocking process …

popey · March 10, 2023, 4:56pm

It didn’t. But now it randomly works where it previously didn’t. I changed nothing.

alan@ziggy:~$ snap changes
ID   Status  Spawn                   Ready                   Summary
105  Done    yesterday at 17:17 GMT  yesterday at 17:17 GMT  Refresh "x16emu" snap
106  Done    today at 11:44 GMT      today at 11:45 GMT      Install "mailspring" snap
107  Done    today at 14:37 GMT      today at 14:37 GMT      Auto-refresh snap "core18"
108  Done    today at 14:45 GMT      today at 14:45 GMT      Refresh all snaps: no updates
109  Done    today at 14:45 GMT      today at 14:45 GMT      Refresh all snaps: no updates
110  Done    today at 15:57 GMT      today at 15:57 GMT      Refresh all snaps: no updates
111  Done    today at 16:55 GMT      today at 16:55 GMT      Refresh snap "snapcraft"
112  Done    today at 16:56 GMT      today at 16:56 GMT      Refresh all snaps: no updates

popey · March 10, 2023, 5:20pm

Thinking about it, while this shouldn’t make any difference, when I was trying earlier (those changes at 108, 109, 110, i was doing snap refresh in the terminal, and then typing my password in the desktop popup.

When it worked, on change 111, I’d done *sudo* snap refresh. I can’t reproduce that right now, but that’s all I can think that differed in the 20 mins between my first post and you replying.

miguelpires · March 14, 2023, 3:04pm

Hi. My guess is that snapcraft starts other processes that stick around after it closes. Snapd checks if a snap is running by looking for its cgroup scope, so if there a snap leaves processes hanging after it exits, the snap is thought to be running. If you could, when this happens again, please run systemctl status and look for a snap scope named something like “snap.snapcraft.*.scope”. If you find anything, please copy the entries under that scope and paste them here. That would help us confirm this hypothesis.

Thanks

sergiusens · March 15, 2023, 11:28am

The only things we identified as blocking snapcraft from updating:

running a build at the time
signing; we use snapd to sign and it starts a gpg-agent which never goes away

The former is valid use case, the latter is someone of a bug; @pedronis any update on how we should work this one out?

popey · March 15, 2023, 2:11pm

I wasn’t doing either of those. I’d only use snapcraft to do remote builds. Maybe there is something lurking from those?

ernestl · March 16, 2023, 9:09am

Perhaps try and reproduce (revert snapcraft, do remote build) and and see what comes up by looking at cgroup scope

popey · March 16, 2023, 11:06am

Sadly I already removed snapcraft from the machine, so i cannot revert, and snap doesn’t allow me to install an older version. The only way I can see to do this, I suspect is to install snapcraft from the edge channel, run it, and wait for an update.

@ernestl - see nothing about cgroups scope checking in your link?

ernestl · March 17, 2023, 1:41pm

Apologies, incorrect link. I meant to refer to this comment: "Close the app to avoid disruptions" for a closed app

popey · March 28, 2023, 6:42pm

Ok, had this again. It’s git credential caching being spawned by snapcraft remote-build.

alan@ziggy:~$ systemd-cgls | grep -A 2 snapcraft | head -n 2
│   │ │ ├─snap.snapcraft.snapcraft.fbf5303c-5c82-456b-8c55-0a61e1a5fa37.scope (#96991)
│   │ │ │ └─410713 /usr/lib/git-core/git credential-cache--daemon /home/alan/.c…
alan@ziggy:~$ ps aux | grep credential | grep -v grep
alan      410713  0.0  0.0  12904  4104 pts/10   S    16:51   0:00 /usr/lib/git-core/git credential-cache--daemon /home/alan/.cache/git/credential/socket
alan@ziggy:~$ snap refresh --list
Name       Version                   Rev   Size  Publisher   Notes
snapcraft  7.3.1.post32+gitb9d447e1  9026  66MB  canonical✓  classic
alan@ziggy:~$ sudo snap refresh
[sudo] password for alan: 
All snaps up to date.
alan@ziggy:~$ snap refresh --list
Name       Version                   Rev   Size  Publisher   Notes
snapcraft  7.3.1.post32+gitb9d447e1  9026  66MB  canonical✓  classic
alan@ziggy:~$ kill -9 410713
alan@ziggy:~$ ps aux | grep credential | grep -v grep
alan@ziggy:~$ snap refresh --list
Name       Version                   Rev   Size  Publisher   Notes
snapcraft  7.3.1.post32+gitb9d447e1  9026  66MB  canonical✓  classic
alan@ziggy:~$ sudo snap refresh
snapcraft (edge) 7.3.1.post32+gitb9d447e1 from Canonical✓ refreshed
alan@ziggy:~$