SUMMARY Switching back to a user with Icon-only Task manager causes panel and widgets to become unresponsive for 2-5 mins. STEPS TO REPRODUCE 1. Setup icons-only task manager for user1 2. Switch users to user2 but keep user1 logged in 3. Wait a while (up to 30 mins) 4. Switch back to user1 OBSERVED RESULT When switching back to User1, plasmashell CPU usage hits 100% and all panels and widgets become unresponsive for 2-5 mins. Forced restart of plasmashell fixes problem. EXPECTED RESULT SOFTWARE/OS VERSIONS Linux/KDE Plasma: Kubuntu 18.04 Kernel: 4.15.0-39-generic CPU: Intel Core i7-4770 GPU: Radeon RX 550 (open drivers) KDE Plasma Version: 5.12.7 KDE Frameworks Version: 5.44.0 Qt Version: 5.9.5 ADDITIONAL INFORMATION Tried turning off compositing but made no difference. Only way to fix this is to remove icons-only task manager and issue stops. Forced restart of plasmashell also fixes problem.
Can you attach gdb and see where it's hanging?
Marking as needsinfo. To expand on Kai's comment: From a konsole sudo gdb `pidof plasmashell` when it connects type "bt" and paste the result here
Attaching to program: /usr/bin/plasmashell, process 2745 [New LWP 2756] [New LWP 2761] [New LWP 2831] [New LWP 2870] [New LWP 2906] [New LWP 2914] [New LWP 2915] [New LWP 2916] [New LWP 2917] [New LWP 2918] [New LWP 2919] [New LWP 2920] [New LWP 3086] [New LWP 3175] [New LWP 3234] [New LWP 3705] [New LWP 3706] [New LWP 3707] [New LWP 3708] [New LWP 3709] [New LWP 3710] [New LWP 3711] [New LWP 3712] [New LWP 3713] [New LWP 3714] [New LWP 3715] [New LWP 3716] [New LWP 3717] [New LWP 3718] [New LWP 3719] [New LWP 3720] [Thread debugging using libthread_db enabled] Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1". 0x00007fe27fb6b697 in ?? () from /usr/lib/x86_64-linux-gnu/libKF5Service.so.5 (gdb) bt #0 0x00007fe27fb6b697 in ?? () from /usr/lib/x86_64-linux-gnu/libKF5Service.so.5 #1 0x00007fe27fb64a58 in ?? () from /usr/lib/x86_64-linux-gnu/libKF5Service.so.5 #2 0x00007fe27fb64b72 in KService::KService(QDataStream&, int) () from /usr/lib/x86_64-linux-gnu/libKF5Service.so.5 #3 0x00007fe27fb6c3c5 in KServiceFactory::createEntry(int) const () from /usr/lib/x86_64-linux-gnu/libKF5Service.so.5 #4 0x00007fe27fb6d246 in KServiceFactory::serviceOffers(int, int) () from /usr/lib/x86_64-linux-gnu/libKF5Service.so.5 #5 0x00007fe27fb7d8ef in KServiceTypeTrader::defaultOffers(QString const&, QString const&) const () from /usr/lib/x86_64-linux-gnu/libKF5Service.so.5 #6 0x00007fe27fb7dc29 in KServiceTypeTrader::query(QString const&, QString const&) const () from /usr/lib/x86_64-linux-gnu/libKF5Service.so.5 #7 0x00007fe19f96818a in TaskManager::windowUrlFromMetadata(QString const&, unsigned int, QExplicitlySharedDataPointer<KSharedConfig>, QString const&) () from /usr/lib/x86_64-linux-gnu/libtaskmanager.so.6 #8 0x00007fe19f9746f7 in TaskManager::XWindowTasksModel::Private::windowUrl(unsigned long long) () from /usr/lib/x86_64-linux-gnu/libtaskmanager.so.6 #9 0x00007fe19f974a5b in TaskManager::XWindowTasksModel::Private::appData(unsigned long long) () from /usr/lib/x86_64-linux-gnu/libtaskmanager.so.6 #10 0x00007fe19f976c60 in TaskManager::XWindowTasksModel::data(QModelIndex const&, int) const () from /usr/lib/x86_64-linux-gnu/libtaskmanager.so.6 #11 0x00007fe27d32d688 in QAbstractProxyModel::data(QModelIndex const&, int) const () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5 #12 0x00007fe19f6ebfe4 in KConcatenateRowsProxyModel::data(QModelIndex const&, int) const () from /usr/lib/x86_64-linux-gnu/libKF5ItemModels.so.5 #13 0x00007fe27d344869 in QSortFilterProxyModel::data(QModelIndex const&, int) const () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5 #14 0x00007fe19f955027 in TaskManager::TaskGroupingProxyModel::data(QModelIndex const&, int) const () from /usr/lib/x86_64-linux-gnu/libtaskmanager.so.6 #15 0x00007fe19f957a37 in ?? () from /usr/lib/x86_64-linux-gnu/libtaskmanager.so.6 #16 0x00007fe27d34b6b2 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5 #17 0x00007fe27d34cc58 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5 #18 0x00007fe27d3b25b5 in QMetaObject::activate(QObject*, int, int, void**) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5 #19 0x00007fe27d31e84c in QAbstractItemModel::dataChanged(QModelIndex const&, QModelIndex const&, QVector<int> const&) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5 #20 0x00007fe19f95498d in TaskManager::TaskGroupingProxyModel::Private::sourceDataChanged(QModelIndex, QModelIndex, QVector<int> const&) () from /usr/lib/x86_64-linux-gnu/libtaskmanager.so.6 #21 0x00007fe19f955bcd in ?? () from /usr/lib/x86_64-linux-gnu/libtaskmanager.so.6 #22 0x00007fe27d3b25b5 in QMetaObject::activate(QObject*, int, int, void**) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5 ---Type <return> to continue, or q <return> to quit--- #23 0x00007fe27d31e84c in QAbstractItemModel::dataChanged(QModelIndex const&, QModelIndex const&, QVector<int> const&) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5 #24 0x00007fe27d34c060 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5 #25 0x00007fe27d34cc58 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5 #26 0x00007fe27d3b25b5 in QMetaObject::activate(QObject*, int, int, void**) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5 #27 0x00007fe27d31e84c in QAbstractItemModel::dataChanged(QModelIndex const&, QModelIndex const&, QVector<int> const&) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5 #28 0x00007fe19f6ec432 in ?? () from /usr/lib/x86_64-linux-gnu/libKF5ItemModels.so.5 #29 0x00007fe19f6ed188 in ?? () from /usr/lib/x86_64-linux-gnu/libKF5ItemModels.so.5 #30 0x00007fe27d3b25b5 in QMetaObject::activate(QObject*, int, int, void**) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5 #31 0x00007fe27d31e84c in QAbstractItemModel::dataChanged(QModelIndex const&, QModelIndex const&, QVector<int> const&) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5 #32 0x00007fe27d340421 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5 #33 0x00007fe27d3420f8 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5 #34 0x00007fe27d3b25b5 in QMetaObject::activate(QObject*, int, int, void**) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5 #35 0x00007fe27d31e84c in QAbstractItemModel::dataChanged(QModelIndex const&, QModelIndex const&, QVector<int> const&) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5 #36 0x00007fe19f971b20 in TaskManager::XWindowTasksModel::Private::dataChanged(unsigned long long, QVector<int> const&) () from /usr/lib/x86_64-linux-gnu/libtaskmanager.so.6 #37 0x00007fe19f972d4a in TaskManager::XWindowTasksModel::Private::windowChanged(unsigned long long, QFlags<NET::Property>, QFlags<NET::Property2>) () from /usr/lib/x86_64-linux-gnu/libtaskmanager.so.6 #38 0x00007fe27d3b26cf in QMetaObject::activate(QObject*, int, int, void**) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5 #39 0x00007fe27fe234eb in KWindowSystem::windowChanged(unsigned long long, QFlags<NET::Property>, QFlags<NET::Property2>) () from /usr/lib/x86_64-linux-gnu/libKF5WindowSystem.so.5 #40 0x00007fe2654777a6 in ?? () from /usr/lib/x86_64-linux-gnu/qt5/plugins/kf5/org.kde.kwindowsystem.platforms/KF5WindowSystemX11Plugin.so #41 0x00007fe27d38058f in QAbstractEventDispatcher::filterNativeEvent(QByteArray const&, void*, long*) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5 #42 0x00007fe26fbc0820 in QXcbConnection::handleXcbEvent(xcb_generic_event_t*) () from /usr/lib/x86_64-linux-gnu/libQt5XcbQpa.so.5 #43 0x00007fe26fbc14ac in QXcbConnection::processXcbEvents() () from /usr/lib/x86_64-linux-gnu/libQt5XcbQpa.so.5 #44 0x00007fe27d3b3122 in QObject::event(QEvent*) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5 #45 0x00007fe27e38b82c in QApplicationPrivate::notify_helper(QObject*, QEvent*) () from /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5 #46 0x00007fe27e3930f4 in QApplication::notify(QObject*, QEvent*) () from /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5 ---Type <return> to continue, or q <return> to quit--- #47 0x00007fe27d3839a8 in QCoreApplication::notifyInternal2(QObject*, QEvent*) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5 #48 0x00007fe27d38611d in QCoreApplicationPrivate::sendPostedEvents(QObject*, int, QThreadData*) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5 #49 0x00007fe27d3dd2c3 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5 #50 0x00007fe2775fd387 in g_main_context_dispatch () from /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0 #51 0x00007fe2775fd5c0 in ?? () from /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0 #52 0x00007fe2775fd64c in g_main_context_iteration () from /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0 #53 0x00007fe27d3dc8ef in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5 #54 0x00007fe27d3819ea in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5 #55 0x00007fe27d38aa84 in QCoreApplication::exec() () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5 #56 0x000056139ec92cfa in ?? () #57 0x00007fe27c9a0b97 in __libc_start_main (main=0x56139ec92320, argc=1, argv=0x7ffede12cd68, init=<optimized out>, fini=<optimized out>, rtld_fini=<optimized out>, stack_end=0x7ffede12cd58) at ../csu/libc-start.c:310 #58 0x000056139ec9309a in _start ()
thanks
I experienced this problem again using the regular Task Manager. #0 0x00007f55565aa22f in QVariant::QVariant(QVariant const&) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5 #1 0x00007f5558d4db02 in ?? () from /usr/lib/x86_64-linux-gnu/libKF5Service.so.5 #2 0x00007f5558d479d5 in ?? () from /usr/lib/x86_64-linux-gnu/libKF5Service.so.5 #3 0x00007f5558d47b72 in KService::KService(QDataStream&, int) () from /usr/lib/x86_64-linux-gnu/libKF5Service.so.5 #4 0x00007f5558d4f3c5 in KServiceFactory::createEntry(int) const () from /usr/lib/x86_64-linux-gnu/libKF5Service.so.5 #5 0x00007f5558d50246 in KServiceFactory::serviceOffers(int, int) () from /usr/lib/x86_64-linux-gnu/libKF5Service.so.5 #6 0x00007f5558d608ef in KServiceTypeTrader::defaultOffers(QString const&, QString const&) const () from /usr/lib/x86_64-linux-gnu/libKF5Service.so.5 #7 0x00007f5558d60c29 in KServiceTypeTrader::query(QString const&, QString const&) const () from /usr/lib/x86_64-linux-gnu/libKF5Service.so.5 #8 0x00007f54781e118a in TaskManager::windowUrlFromMetadata(QString const&, unsigned int, QExplicitlySharedDataPointer<KSharedConfig>, QString const&) () from /usr/lib/x86_64-linux-gnu/libtaskmanager.so.6 #9 0x00007f54781ed6f7 in TaskManager::XWindowTasksModel::Private::windowUrl(unsigned long long) () from /usr/lib/x86_64-linux-gnu/libtaskmanager.so.6 #10 0x00007f54781eda5b in TaskManager::XWindowTasksModel::Private::appData(unsigned long long) () from /usr/lib/x86_64-linux-gnu/libtaskmanager.so.6 #11 0x00007f54781efc60 in TaskManager::XWindowTasksModel::data(QModelIndex const&, int) const () from /usr/lib/x86_64-linux-gnu/libtaskmanager.so.6 #12 0x00007f5556510688 in QAbstractProxyModel::data(QModelIndex const&, int) const () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5 #13 0x00007f5473dd1fe4 in KConcatenateRowsProxyModel::data(QModelIndex const&, int) const () from /usr/lib/x86_64-linux-gnu/libKF5ItemModels.so.5 #14 0x00007f5556527869 in QSortFilterProxyModel::data(QModelIndex const&, int) const () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5 #15 0x00007f54781ce027 in TaskManager::TaskGroupingProxyModel::data(QModelIndex const&, int) const () from /usr/lib/x86_64-linux-gnu/libtaskmanager.so.6 #16 0x00007f54781d0a37 in ?? () from /usr/lib/x86_64-linux-gnu/libtaskmanager.so.6 #17 0x00007f555652e6b2 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5 #18 0x00007f555652fc58 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5 #19 0x00007f55565955b5 in QMetaObject::activate(QObject*, int, int, void**) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5 #20 0x00007f555650184c in QAbstractItemModel::dataChanged(QModelIndex const&, QModelIndex const&, QVector<int> const&) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5 #21 0x00007f54781cd98d in TaskManager::TaskGroupingProxyModel::Private::sourceDataChanged(QModelIndex, QModelIndex, QVector<int> const&) () from /usr/lib/x86_64-linux-gnu/libtaskmanager.so.6 #22 0x00007f54781cebcd in ?? () from /usr/lib/x86_64-linux-gnu/libtaskmanager.so.6 #23 0x00007f55565955b5 in QMetaObject::activate(QObject*, int, int, void**) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5 #24 0x00007f555650184c in QAbstractItemModel::dataChanged(QModelIndex const&, QModelIndex const&, QVector<int> const&) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5 #25 0x00007f555652f060 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5 #26 0x00007f555652fc58 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5 ---Type <return> to continue, or q <return> to quit--- #27 0x00007f55565955b5 in QMetaObject::activate(QObject*, int, int, void**) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5 #28 0x00007f555650184c in QAbstractItemModel::dataChanged(QModelIndex const&, QModelIndex const&, QVector<int> const&) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5 #29 0x00007f5473dd2432 in ?? () from /usr/lib/x86_64-linux-gnu/libKF5ItemModels.so.5 #30 0x00007f5473dd3188 in ?? () from /usr/lib/x86_64-linux-gnu/libKF5ItemModels.so.5 #31 0x00007f55565955b5 in QMetaObject::activate(QObject*, int, int, void**) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5 #32 0x00007f555650184c in QAbstractItemModel::dataChanged(QModelIndex const&, QModelIndex const&, QVector<int> const&) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5 #33 0x00007f5556523421 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5 #34 0x00007f55565250f8 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5 #35 0x00007f55565955b5 in QMetaObject::activate(QObject*, int, int, void**) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5 #36 0x00007f555650184c in QAbstractItemModel::dataChanged(QModelIndex const&, QModelIndex const&, QVector<int> const&) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5 #37 0x00007f54781eab20 in TaskManager::XWindowTasksModel::Private::dataChanged(unsigned long long, QVector<int> const&) () from /usr/lib/x86_64-linux-gnu/libtaskmanager.so.6 #38 0x00007f54781ebd4a in TaskManager::XWindowTasksModel::Private::windowChanged(unsigned long long, QFlags<NET::Property>, QFlags<NET::Property2>) () from /usr/lib/x86_64-linux-gnu/libtaskmanager.so.6 #39 0x00007f55565956cf in QMetaObject::activate(QObject*, int, int, void**) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5 #40 0x00007f55590064eb in KWindowSystem::windowChanged(unsigned long long, QFlags<NET::Property>, QFlags<NET::Property2>) () from /usr/lib/x86_64-linux-gnu/libKF5WindowSystem.so.5 #41 0x00007f553e7cf7a6 in ?? () from /usr/lib/x86_64-linux-gnu/qt5/plugins/kf5/org.kde.kwindowsystem.platforms/KF5WindowSystemX11Plugin.so #42 0x00007f555656358f in QAbstractEventDispatcher::filterNativeEvent(QByteArray const&, void*, long*) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5 #43 0x00007f5548da3820 in QXcbConnection::handleXcbEvent(xcb_generic_event_t*) () from /usr/lib/x86_64-linux-gnu/libQt5XcbQpa.so.5 #44 0x00007f5548da44ac in QXcbConnection::processXcbEvents() () from /usr/lib/x86_64-linux-gnu/libQt5XcbQpa.so.5 #45 0x00007f5556596122 in QObject::event(QEvent*) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5 #46 0x00007f555756e82c in QApplicationPrivate::notify_helper(QObject*, QEvent*) () from /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5 #47 0x00007f55575760f4 in QApplication::notify(QObject*, QEvent*) () from /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5 #48 0x00007f55565669a8 in QCoreApplication::notifyInternal2(QObject*, QEvent*) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5 #49 0x00007f555656911d in QCoreApplicationPrivate::sendPostedEvents(QObject*, int, QThreadData*) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5 #50 0x00007f55565c02c3 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5 #51 0x00007f55507e0387 in g_main_context_dispatch () from /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0 #52 0x00007f55507e05c0 in ?? () from /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0 #53 0x00007f55507e064c in g_main_context_iteration () from /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0 ---Type <return> to continue, or q <return> to quit--- #54 0x00007f55565bf8ef in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5 #55 0x00007f55565649ea in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5 #56 0x00007f555656da84 in QCoreApplication::exec() () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5 #57 0x0000560978caccfa in ?? () #58 0x00007f5555b83b97 in __libc_start_main (main=0x560978cac320, argc=1, argv=0x7ffeb22d6958, init=<optimized out>, fini=<optimized out>, rtld_fini=<optimized out>, stack_end=0x7ffeb22d6948) at ../csu/libc-start.c:310 #59 0x0000560978cad09a in _start ()
I stopped using Icon Only Task manager and still have this problem. When I switch users among family members, Plasmashell freezez for 1-2 mins. If I kill and restart Plasmashell I'm good to go. Maybe this bug needs to be reclassified? Should I create a new one?
This looks like a bug in xcb or elsewhere, and I cannot reproduce the freeze. Is the bug still valid in 5.27?
Dear Bug Submitter, This bug has been in NEEDSINFO status with no change for at least 15 days. Please provide the requested information as soon as possible and set the bug status as REPORTED. Due to regular bug tracker maintenance, if the bug is still in NEEDSINFO status with no change in 30 days the bug will be closed as RESOLVED > WORKSFORME due to lack of needed information. For more information about our bug triaging procedures please read the wiki located here: https://community.kde.org/Guidelines_and_HOWTOs/Bug_triaging If you have already provided the requested information, please mark the bug as REPORTED so that the KDE team knows that the bug is ready to be confirmed. Thank you for helping us make KDE software even better for everyone!
This bug has been in NEEDSINFO status with no change for at least 30 days. The bug is now closed as RESOLVED > WORKSFORME due to lack of needed information. For more information about our bug triaging procedures please read the wiki located here: https://community.kde.org/Guidelines_and_HOWTOs/Bug_triaging Thank you for helping us make KDE software even better for everyone!