I've experienced this hang on my production Kubuntu 17.10 machine a *lot*. Less so on my Neon dev VM, but it happens there too. I see it most often when I click on an app in the list. The delegate turns blue, and then Discover hangs forever. Here's a sample backtrace, in case it helps at all: Thread 1 "plasma-discover" received signal SIGINT, Interrupt. 0x00007ffff338574d in poll () at ../sysdeps/unix/syscall-template.S:84 84 ../sysdeps/unix/syscall-template.S: No such file or directory. (gdb) bt #0 0x00007ffff338574d in poll () at ../sysdeps/unix/syscall-template.S:84 #1 0x00007fffee0ae38c in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0 #2 0x00007fffee0ae49c in g_main_context_iteration () from /lib/x86_64-linux-gnu/libglib-2.0.so.0 #3 0x00007ffff3fb56cb in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5 #4 0x00007ffff3f5de2a in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5 #5 0x00007ffff3f66d64 in QCoreApplication::exec() () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5 #6 0x00000000004162a8 in main () Different issue, or a dupe of Bug 386992?
I can reproduce this on demand by clicking on Digikam from the Featured page while Discover is still loading.
*** Bug 390218 has been marked as a duplicate of this bug. ***
FWIW, this makes Discover almost unusable for me in 5.12 on Kubuntu. I can't hardly go 30 seconds without a hang.
Git commit a2d6e79586b8c73f2e2d6bb1262d348eb53f4b52 by Aleix Pol. Committed on 12/02/2018 at 17:02. Pushed by apol into branch 'Plasma/5.12'. Fix freeze when showing the ApplicationPage Change the strategy to show the screenshots. It sometimes would get the ListView stuck. Use a Row + Repeater instead. Also change the scrolling shadows approach because somehow it wouldn't work with the Row {} M +11 -11 discover/qml/ApplicationPage.qml M +81 -69 discover/qml/ApplicationScreenshots.qml M +1 -0 discover/resources.qrc https://commits.kde.org/discover/a2d6e79586b8c73f2e2d6bb1262d348eb53f4b52
*** Bug 390408 has been marked as a duplicate of this bug. ***
Created attachment 110776 [details] Backtrace - Discove froze after launch Discover still freezes a lot on my system using KDE Frameworks 5.43.0, Qt 5.9.3 on Neon 5.12.1, 64-bit Kernel 4.4.0-112 The freezes seem to happen the most frequently on a new user account I set up (for bug triaging). In case it helps, I'm attaching a gdb backtrace of one freeze. What I did to make that freeze happen: I simply launched Discover from Kicker and it froze instantly. I had logged in just 5 min ago. The freezes are rarely reproducible with the same action. Once it froze after clicking Settings, and once it froze when I searched for an app.
Created attachment 110780 [details] Backtrace: Discover froze when searching for app (Sorry, that previous backtrace was probably not complete. I'm new to this and trying to learn). Discover just crashed again. Attaching gdb backtrace (the full one now, I hope). What I did: - Launched Discover - Started typing for an app ('keepass') - Hit Enter - Window froze and Discover became unresponsive
Make sure you have the latest stable PackageKit Qt.
(In reply to Aleix Pol from comment #8) > Make sure you have the latest stable PackageKit Qt. Packagekit is 1.1.8-0neon1. I already have an updated system (Neon user edition).