Hi,
on Intel X3220 CPU based systems (4 physical cores) I came across the
following thing (Debian etch, with vanilla kernel 2.6.25.9):
starting the following:
$ screen -d -m stress -c 2
$ nice -19 screen -d -m stress -c 4
This causes two cores to be 100% busy in user state and one core to be
busy in 100% nice state. However, the remaining core is idle. Even
watching it over longer stretches of time, the situation remains static.
I guess it's a kernel misconfiguration on my part (config available here:
https://n0.aei.uni-hannover.de/linux/kernel/config-2.6.25.9-nodes
), but if not could this be a scheduling bug?
Thanks for any hint
Cheers
Carsten