mutex error while throttling down a phenom CPU

Joerg Bergmann email at jbergmann.de
Sat Jan 17 20:03:25 UTC 2009


Sorry for hijacking threads. This is a _new_ mail.

uname -a:
Linux phenom.phy.tu-dresden.de 2.6.27.9-73.fc9.i686 #1 SMP Tue Dec 16 
15:25:05 EST 2008 i686 athlon i386 GNU/Linux

Phenom 2750 2.4 GHz 125W, Gigabyte MA790X-DS4 mainboard,
4GB DDR2 ECC RAM

It's my own numerical pthread multithreaded application BGMN
(www.bgmn.de). I the past, prior to Phenom and Fedora 9, BGMN worked OK.
Fedora early in 2008, BGMN worked OK (I got a warning message early at
boot time about disabled quit'n'cool). Starting in Autumn, I observed
BGMN to stop accidentally. BGMN uses a master thread and 1...4 slave
threads. On 2...4 slave threads, slave threads communicate using
mutexes. With 1 slave thread, these mutexes leave unused. BGMN did never
stop when using only 1 slave thread. One time, I got accidentally an
error while freeing a mutex. As a workaround, I did set MAX_SPEED
and MIN_SPEED to 2400 in /etc/sysconfig/cpuspeed. That worked,
even with 4 threads the program seems to run properly.

Anyone similar observations?

Joerg




More information about the fedora-test-list mailing list