Archive for January, 2013

hibernate/sleep fails on second attempt

Posted in Uncategorized on January 29, 2013 by voline

Problem

I’d never had problems with suspend/sleep on any machine.  So imagine my surprise when one day it all of a sudden broke, and not only that hibernate broke as well.  I use tux-on-ice for its superior hibernation support, so I thought perhaps there was a bug in that.  But to my dismay, even the stock kernel had the same issues.

What was strange was that it was completely reproducible.  After doing a regular boot, I could suspend/hibernate and wakeup/resume once, but the second time the machine would lock up with a blank screen.  The only way to get back to a usable system was to do a hard reset or let the power run out (after which of course there was no usable hibernation image).

What was so infuriating was that I could get absolutely no information about what the problem was.  I tried doing various test using /sys/power/pm_test, but everything checked out fine.  Nothing in syslog indicated any problem. I did many google searches and read tons of suspend/hibernation issues and fixes.  None of them worked or applied to me.  I even tried to use /sys/power/pm_trace to figure out where in the kernel it was hanging.  All to no avail.

I was quickly running out of leads.  Finally, in a desperate attempt at finding the problem, I wrote some scripts to tell me all the packages I’d installed since the problem started occurring.  I culled the list down to ones that could conceivably affect the kernel.  The list was very short, but cgroup-bin appeared on there and much to my surprise this problem went away when I went back to cgroups-lite, which is the default ubuntu package.  Now that I knew the culprit, I googled some more and found a pre-existing bug in launchpad for this issue.

Solution (Work around)

Uninstall cgroups-bin

* NOTE: It appears as this issue may now be fixed in Ubuntu, as I now (several months later) have cgroups-bin installed and suspend/hibernation working.

Reference

Work around hard to read digikam tooltips in Ubuntu

Posted in Uncategorized on January 29, 2013 by voline

Problem

For sometime I’d been living with a rather annoying problem. The tooltips in digikam for every ubuntu (gnome/unity based) I’ve used have been virtually unreadable. Basically the text is dark grey on a black background. After more research than I wanted to do to solve this issue, here’s what I came up with for the benfit of others (and myself when I need this again).

Solution (work around)

Ultimately a fix needs to come from either KDE, Ubuntu or both, so this is just a work around. This should work for similar problems in other KDE apps, but I’ve not tested that. First make sure digikam (or the program with the unreadable tooltips) is running. Then go to the system settings application and select the “Appearance” settings. In the “Theme” section, switch to a different theme, then back to the original. Voila! Your tooltips should have changed to be readable now. This will need to be done everytime the application is started.  Feel free to post better solutions or figure out how to fix this annoying bug!

Alternative Solutions

These may work if the above does not.  I’ve tried some and it didn’t solve the problem:

Reference Material