Bug 441954

Summary:	Discover gets stuck for a long time during fetching updates with zypper PK plugin
Product:	[Applications] Discover	Reporter:	davidkacerek
Component:	PackageKit	Assignee:	Dan Leinir Turthra Jensen <leinir>
Status:	RESOLVED FIXED
Severity:	normal	CC:	aleixpol, joseph, nate
Priority:	NOR	Keywords:	efficiency-and-performance
Version First Reported In:	5.18.6
Target Milestone:	---
Platform:	openSUSE
OS:	Linux
Latest Commit:		Version Fixed/Implemented In:
Sentry Crash Report:
Attachments:	pkmon.log pkmon_pkcon.log

Description davidkacerek 2021-09-03 16:50:01 UTC

OVERVIEW
When Discover is fetching updates, it takes a lot of time compared to when getting updates with the native package manager (ZYpp) or pkcon client.

STEPS TO REPRODUCE
1. Install PackageKit-backend-zypp
2. Run plasma-discover --mode Update

OBSERVED RESULT
Fetching updates takes disproportionately long time (~10 min).

EXPECTED RESULT
Fetching updates takes approximately same time as native pkg mgr or pkcon client.

SOFTWARE/OS VERSIONS
openSUSE version: Leap 15.3
KDE Plasma Version: 5.18.6
KDE Frameworks Version: 5.76.0
Qt Version: 5.12.7

ADDITIONAL INFORMATION
The problem goes away when switching back-ends from PackageKit-backend-zypp -> PackageKit-backend-dnf. This might indicate a bug in the ZYpp back-end, however, with DNF, there are no respositories set in Discover settings except "lvfs - Linux Vendor Firmware Service" so DNF has got some mitigating circumstance. 

Moreover, If I disable all repositories while using the ZYpp back-end, the problem goes away too.

I've also checked I'm not stuck while running "pkcon get-updates" so likely the problem is not within the ZYpp back-end but in Discover.

A follow-up to https://bugs.kde.org/show_bug.cgi?id=440103.

Comment 1 davidkacerek 2021-09-03 16:51:01 UTC

Created attachment 141273 [details]
pkmon.log

The whole pkmon output while launching "plasma-discover --mode Update", waiting a long time till it finishes searching for updates, and then turning Discover off.

Comment 2 Nate Graham 2021-09-08 21:22:26 UTC

Unfortunately this is a known issue with openSUSE's PackageKit plugin for the Zypper package manager. It's just really slow. The fact that pkmon shows the slowness too is a clue.

Comment 3 davidkacerek 2021-09-08 22:17:30 UTC

(In reply to Nate Graham from comment #2)
> Unfortunately this is a known issue with openSUSE's PackageKit plugin for
> the Zypper package manager. It's just really slow. The fact that pkmon shows
> the slowness too is a clue.

Isn't the PackageKit plugin for ZYpp also used when doing "pkcon get-updates"? If the problem is in the ZYpp plugin, "pkcon get-updates" would be stuck too, wouldn't it?

Unfortunatelly, pkmon output doesn't indicate anywhere it's slow because of ZYpp. Actually the lines in the output look the same when "pkcon get-updates" is run - only, it's much shorter.

Also, You say it's a known openSUSE issue. In that case it should have been reported but looking at their bugzilla at bugzilla.opensuse.org, I couldn't find the issue there when searching for "discover" keyword among opened issues...

I'd just like to make sure about this before reporting this to openSUSE,
thanks for clarification.

Comment 4 davidkacerek 2021-09-08 22:19:27 UTC

Created attachment 141411 [details]
pkmon_pkcon.log

pkmon output while launching "pkcon get-updates", and then waiting a short while till pkcon finishes.

Comment 5 Nate Graham 2021-09-08 22:44:23 UTC

Oh, NOT stuck with `pkcon get-updates`. I misread that, sorry.

Yes in this case there may be an issue in Discover itself, you're right.

Comment 6 Aleix Pol 2021-09-23 22:18:57 UTC

We have been looking into and addressing certain issues in our OCS integration (for KNewStuff) that could be the culprit. Your experience should improve as you upgrade to KDE Frameworks 5.87.

That said, I've been debugging this issue and it took 30s to 1 minute tops, never as long as 10 minutes.