[Mageia-dev] Anybody having high CPU by kded4 after upgrading to 4.6.90?

Sat Jul 2 09:45:15 CEST 2011

2011/7/1 Christiaan Welvaart <cjw at daneel.dyndns.org>:
+> On Fri, 1 Jul 2011, Radu-Cristian FOTESCU wrote:
+>
+>> Now, it's tough to determine what exactly is making kded4 to eat the CPU.
+>> As I'm having a single core, I'm burned. At the same time, minor changes
+>> that are actually small improvements make me want to stay with 4.6.90, not
+>> to revert to 4.6.4....
+>
+> One way to figure that out is to attach gdb to it while it's running and
+> then print a backtrace. If you do that several times, you may break in the
+> code that's running a lot. But even if that works it is likely still not
+> easy to figure out what's going on.
+>
+> Other ways to get information would be to strace (or ltrace) this daemon to
+> get an idea what it's trying to do. But CPU usage by the application itself
+> cannot be seen this way.
+>
+> An easier way to start is to run iotop and check if kded4 is doing any I/O
+> related to this cpu usage.
+
+Did that (after installing all updates up to 07:00 UTC), no signs of
+any I/O activity other than the usual. Still, one of the 4 cores is on
+full load. What strikes me here is:
+ - on a CPU with 1 core, this is fully loaded
+ - on a dual core CPU only 1 core is loaded
+ - on a quadcore CPU only 1 core is loaded.
+
+So, whatever it is, it affects only one CPU core no matter how many
+cores the CPU offers.
+
+-- 
+wobo
+