QGIS » QGIS Application

I just got an update to: Version: 1:2.18.1+20trusty ... and it did the same. Here are all the screen messages:

Warning: loading of qgis translation failed [/usr/share/qgis/i18n//qgis_en_CA]
Warning: loading of qt translation failed [/usr/share/qt4/translations/qt_en_CA]
Warning: QCss::Parser - Failed to load file "/style.qss"
Warning: QLayout: Attempting to add QLayout "" to QgsPanelWidgetStack "mWidgetStack", which already has a layout
Warning: Loading a file that was saved with an older version of qgis (saved in 2.14.3-Essen, loaded in 2.18.1). Problems may occur.
setLayerType: OpenStreetMap
Warning: QPainter::begin: A paint device can only be painted by one painter at a time.
Segmentation fault

....it ran fine with very little data showing. As soon as I turned on a larger number of layers (20) it crashed on the segmentation fault immediately.

Installed 2.18.2+20 trusty, same result exactly. Hardly surprising since this bug is unaddressed, but there's always hope a different bug fix will catch this one as a side-effect. With "Segmentation fault" I can only assume that somebody has introduced a massive memory leak for layers coming fro PostGIS queries. It runs for a bout of a minute of pans and zooms and usually crashes on a major "zoom out" that would pull in a lot more data from PosGIS.

Nope, no problem like this has happened to me since 2.4. I could do anything in 2.14 or 2.16, never a crash.

I just watched the error messages as I finally made the failure replicable: turn on ONE MORE LAYER at one point, and this happened:

Warning: QPainter::begin: A paint device can only be painted by one painter at a time.
Segmentation fault

...and the whole program goes blank. Alas, I cannot figure out how, in Linux, to tell Linux Mint to "downgrade" me back to 2.16, as QGIS upgrades simply show up in my upgrades queue when they hit Mint's repository.

Thanks for giving this a look!

Mixed results! Once I got downgraded to 2.14 from the repository you explained to me (a thousand thanks, there, I simply didn't understand how to pick repositories before), I loaded in a project and it crashed immediately. Then I loaded the project I was working on yesterday, and having to re-start every 30 minutes or so from crashes...which I only avoided by trying to keep the info on-screen down to a minimum of needed layers.

That project worked fine for FAR longer than it ever did yesterday, didn't crash in 20 minutes of heavy "zooming out" to bring a gigabyte or more of PostGIS queries on-screen - multiple dense layers.

Then I went back to the project that crashed and got a new behaviour - screen freezing though the app didn't go away. Finally, I triggered a crash with it after a command-line start, giving me the error messages:

====================================
roy@royz ~/Desktop $ qgis OWWA.qgs
Warning: loading of qgis translation failed [/usr/share/qgis/i18n//qgis_en_CA]
Warning: loading of qt translation failed [/usr/share/qt4/translations/qt_en_CA]
Warning: QCss::Parser - Failed to load file "/style.qss"
pure virtual method called
Warning: QPainter::begin: A paint device can only be painted by one painter at a time.
Warning: QPainter::setRenderHint: Painter must be active to set rendering hints
Warning: QPainter::setBrush: Painter not active
Warning: QPainter::setPen: Painter not active
Warning: QPainter::translate: Painter not active
Warning: QPainter::drawPath: Painter not active
Warning: QPainter::end: Painter not active, aborted
terminate called without an active exception
Aborted
roy@royz ~/Desktop $ ^C
roy@royz ~/Desktop $ qgis OWWA.qgs
Warning: loading of qgis translation failed [/usr/share/qgis/i18n//qgis_en_CA]
Warning: loading of qt translation failed [/usr/share/qt4/translations/qt_en_CA]
Warning: QCss::Parser - Failed to load file "/style.qss"
Warning: QPainter::begin: A paint device can only be painted by one painter at a time.
Warning: QPainter::setRenderHint: Painter must be active to set rendering hints
Warning: QPainter::setBrush: Painter not active
Warning: QPainter::setPen: Painter not active
Warning: QPainter::translate: Painter not active
Warning: QPainter::drawPath: Painter not active
Warning: QPainter::end: Painter not active, aborted
Segmentation fault ===================================
...

Then I tried yet another project, an even larger one. That one crashed simply attempting to OPEN the file....and I tried again and it opened this time. I panned around the map a little and got a burst of error messages from "QPainter", but no crash. Then zoomed out a little more to bring in more info an it crashed instantly.

=========================
roy@royz ~/Desktop $ qgis YYC_GIS.qgs
Warning: loading of qgis translation failed [/usr/share/qgis/i18n//qgis_en_CA]
Warning: loading of qt translation failed [/usr/share/qt4/translations/qt_en_CA]
Warning: QCss::Parser - Failed to load file "/style.qss"
Warning: QPainter::begin: A paint device can only be painted by one painter at a time.
Warning: QPainter::setRenderHint: Painter must be active to set rendering hints
Warning: QPainter::setBrush: Painter not active
Warning: QPainter::setPen: Painter not active
Warning: QPainter::translate: Painter not active
Warning: QPainter::drawPath: Painter not active
Warning: QPainter::end: Painter not active, aborted
Segmentation fault <<<<<<<<<<<CRASH IN THE MIDDLE OF LOADING THE PROJECT FILE

roy@royz ~/Desktop $ qgis YYC_GIS.qgs <<<<<<<<<<<<SECOND ATTEMPT A MOMENT LATER
Warning: loading of qgis translation failed [/usr/share/qgis/i18n//qgis_en_CA]
Warning: loading of qt translation failed [/usr/share/qt4/translations/qt_en_CA]
Warning: QCss::Parser - Failed to load file "/style.qss"
Warning: QPainter::begin: A paint device can only be painted by one painter at a time. <<<<BURST OF MESSAGES DURING PAN, BUT NO CRASH
Warning: QPainter::setRenderHint: Painter must be active to set rendering hints
Warning: QPainter::setBrush: Painter not active
Warning: QPainter::setPen: Painter not active
Warning: QPainter::translate: Painter not active
Warning: QPainter::drawPath: Painter not active
Warning: QPainter::end: Painter not active, aborted
pure virtual method called <<<<<<<<<ZOOM OUT AND IMMEDIATE CRASH
Warning: QPainter::begin: A paint device can only be painted by one painter at a time.
Warning: QPainter::setRenderHint: Painter must be active to set rendering hints
Warning: QPainter::setBrush: Painter not active
Warning: QPainter::setPen: Painter not active
Warning: QPainter::translate: Painter not active
Warning: QPainter::drawPath: Painter not active
Warning: QPainter::end: Painter not active, aborted
terminate called without an active exception
Warning: QPainter::begin: A paint device can only be painted by one painter at a time.
Aborted =============================

Then I went back to the one that didn't crash, and used it longer...and it finally crashed the way it did so many times yesterday, when I turned on a really quite small layer that puts street names on top of all the much-busier linework of buildings, contour lines, etc.

=================
roy@royz ~/Desktop $ qgis Storm.qgs
Warning: loading of qgis translation failed [/usr/share/qgis/i18n//qgis_en_CA]
Warning: loading of qt translation failed [/usr/share/qt4/translations/qt_en_CA]
Warning: QCss::Parser - Failed to load file "/style.qss" <<<<<<<<<<< Messges upon start up. No more messages until the layer was turned on, then:
Warning: QPainter::begin: A paint device can only be painted by one painter at a time.
Warning: QPainter::setRenderHint: Painter must be active to set rendering hints
Warning: QPainter::setBrush: Painter not active
Warning: QPainter::setPen: Painter not active
Segmentation fault ==============================

So, in short....crap. It's about more than just qgis version 2.16. Though I'm certain that 2.14 was MORE stable than 2.16, which would have crashed 3 times in the time I used it. But when I re-started, I could crash it at once by turning on that "street names" layer and doing almost anything.

Man, I guess I need to regress backwards in my whole Linux version here? It's an underlying library at fault, not QGIS???

Have you tried removing your .qgis2 folder and testing with NO plugins loaded?

Excellent Suggestion! I feel dumb for not thinking of that. Alas, it didn't work. At all.

oy@royz ~/Desktop $ qgis YYC_GIS.qgs
Warning: loading of qgis translation failed [/usr/share/qgis/i18n//qgis_en_CA]
Warning: loading of qt translation failed [/usr/share/qt4/translations/qt_en_CA]
Warning: QCss::Parser - Failed to load file "/style.qss"
QInotifyFileSystemWatcherEngine::addPaths: inotify_add_watch failed: No such file or directory
Warning: QFileSystemWatcher: failed to add paths: /home/roy/.qgis2//project_templates
Segmentation fault <<<<<<<<<<<<<< CRASHED ON START-UP, AGAIN

roy@royz ~/Desktop $ qgis YYC_GIS.qgs
Warning: loading of qgis translation failed [/usr/share/qgis/i18n//qgis_en_CA]
Warning: loading of qt translation failed [/usr/share/qt4/translations/qt_en_CA]
Warning: QCss::Parser - Failed to load file "/style.qss"
QInotifyFileSystemWatcherEngine::addPaths: inotify_add_watch failed: No such file or directory
Warning: QFileSystemWatcher: failed to add paths: /home/roy/.qgis2//project_templates
Segmentation fault

....AND THE SECOND TIME, IT STARTED, BUT CRASHED INSTANTLY UPON SOME ZOOMING.

These crashes are courtesy of my "Kitchen Sink" project that has EVERY layer in Calgary on it. (I was Sr.Infrastructure Engineer for Calgary Water, and routinely loaded in all the Water, Sanitary Sewer and Storm Sewer layers, which were minor compared to every street, building, park, legal lot, and tree.) This project has them all, though only about a dozen turned on at start-up. But they are big ones: the buildings, etc. Rendering would take minutes if I zoomed out to the full city, so I don't; dense layers like buildings and legal lots turn off at 1:4000 or so. There are rarely hundreds of megabytes on-screen at any time.

With fewer layers on, I just got a few hours of work done with 2.14 and no crashes.

Please also try the latest version available 2.18.4