I've hit an issue, which I believe I've now isolated to have come from upgrading fontconfig (and related packages) from 2.12.6-0ubuntu2 to 2.12.6-0ubuntu2.3 from -proposed: if I start Firefox and afterwards start Gparted or Synaptic, Firefox starts eating up all of my CPU. Eventually all letters in the Gparted/Synaptic UI turn into boxes.
Syslog typically then says something like below: Dec 4 13:41:50 saegusa synaptic.desktop[30027]: (synaptic:30028): Pango-WARNING **: 13:41:50.995: failed to create cairo scaled font, expect ugly output. the offending font is 'DejaVu Sans 11' Dec 4 13:41:50 saegusa synaptic.desktop[30027]: (synaptic:30028): Pango-WARNING **: 13:41:50.995: font_face status is: out of memory Dec 4 13:41:50 saegusa synaptic.desktop[30027]: (synaptic:30028): Pango-WARNING **: 13:41:50.995: scaled_font status is: out of memory Dec 4 13:41:50 saegusa synaptic.desktop[30027]: (synaptic:30028): Pango-WARNING **: 13:41:50.995: shaping failure, expect ugly output. shape-engine='PangoFcShapeEngine', font='DejaVu Sans 11', text='Päivitä' Dec 4 13:41:51 saegusa synaptic.desktop[30027]: (synaptic:30028): Pango-WARNING **: 13:41:51.007: failed to create cairo scaled font, expect ugly output. the offending font is 'DejaVu Sans 11' Dec 4 13:41:51 saegusa synaptic.desktop[30027]: (synaptic:30028): Pango-WARNING **: 13:41:51.007: font_face status is: out of memory Dec 4 13:41:51 saegusa synaptic.desktop[30027]: (synaptic:30028): Pango-WARNING **: 13:41:51.007: scaled_font status is: out of memory The computer has 32 GB of memory and there's plenty still usable when this occurs, so the OOM seems incorrect to me. To be sure, I rolled back entirely from -proposed (which caused the issue to go away), then re-enabled -proposed and upgraded just fontconfig, and the issue reappeared. -- You received this bug notification because you are a member of Desktop Packages, which is subscribed to fontconfig in Ubuntu. https://bugs.launchpad.net/bugs/1803534 Title: Backport uuid based cache file naming scheme Status in fontconfig package in Ubuntu: New Status in fontconfig source package in Bionic: Fix Committed Bug description: Fontconfig 2.13.0 changed the cache file naming scheme to be based on the contents of ".uuid" file in the directory rather than a hash of the directory name. On a pure debs system this doesn't really matter since everything is using the same libfontconfig.so. When snaps are involved, it can lead to some apps not seeing the cache files produced by a different fontconfig version. In particular, while libfontconfig 2.13 can reuse 2.12's cache files for read only directories, the reverse is not true. This will be a problem for apps built on top of the "core18" base snap when run on later Ubuntu releases (cosmic, disco, etc). By providing a backport of the UUID cache file feature to bionic for use by snap applications, we'd avoid this. Having it in bionic- updates would be ideal so that snapcraft picks it up automatically. [Impact] * This update changes how fontconfig cache files are named, instead of using md5($dir), it instead uses the contents of a $dir/.uuid file. No changes are made to the format of the cache file contents. * This change is primarily intended for use by snap applications built with core18: as the updated libfontconfig will fall back to the md5 cache file names for read-only directories without a .uuid file, they will be able to reuse cache files from any host system running fontconfig >= 2.11.95 [Test Case] * After installing the update, cache files should be generated in /var/cache/fontconfig/ with names like "07b67f7a-16ea-4440-9b6c- 21fc9153568c-le64.cache-7" (note the extra dashes not present in the MD5 based cache file names). [Regression Potential] * Applications using a non-default libfontconfig could end up not finding the new cache files and regenerating them in ~/.cache/fontconfig. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/fontconfig/+bug/1803534/+subscriptions -- Mailing list: https://launchpad.net/~desktop-packages Post to : desktop-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~desktop-packages More help : https://help.launchpad.net/ListHelp
