Hi On Mon, Apr 16, 2012 at 2:32 PM, Srivatsa S. Bhat <srivatsa.bhat(a)linux.vnet.ibm.com&gt; wrote: yep, thank you very much, that seems to be the reason That's sad to learn!, I am going to move all my VMs to session libvirt then :) thanks -- Marc-André Lureau

On 04/16/2012 09:43 PM, Daniel P. Berrange wrote: Thanks for the confirmation. The script below might work as a temporary workaround. I don't think that would be all that complicated.. Below is a script that should do the trick, for all cases, including existing running VMs. This script is not at all specific to libvirt by the way (as the problem itself is not at all libvirt specific). It saves the cpuset configuration before suspend and restores it after resume, for all cpusets (not only the ones controlled by libvirt). Of course, it hooks onto the pm-utils mechanism, as you mentioned. Regards, Srivatsa S. Bhat IBM Linux Technology Center Note: Put this script in /usr/<lib or lib64>/pm-utils/sleep.d by prefixing appropriate number (eg: /usr/lib64/pm-utils/sleep.d/02cpusets.sh). And then give execute permissions to the script. It will save all the cpusets' cpu configuration before suspend and restore them after resume. This is a workaround until the problem gets fixed in the kernel. cpusets.sh ---- #! /bin/bash # Script to save and restore the cpusets' cpu configuration after a # suspend/resume cycle. # This is a workaround for a Linux kernel bug which results in cpusets # being reduced to a single cpu (boot cpu) after a suspend/resume # cycle. # # Author: Srivatsa S. Bhat <srivatsa.bhat(a)linux.vnet.ibm.com&gt; # 16 March 2012 # save_cpusets() { rm -f saved_cpusets.txt # Check if cpusets are mounted separately dir=`mount | grep cpuset` if [ -z "$dir" ]; then # Check if atleast cgroup is mounted dir=`mount | grep cgroup` if [ -z "$dir" ]; then #Nothing to be done, as cpusets are not being used exit 0 fi fi dir=`mount | grep cpuset | cut -d' ' -f3` # Omit the root cpuset (using mindepth parameter) since it is read-only # (and will be restored properly after resume by the kernel itself). # Sorting is necessary because otherwise the hierarchy is not preserved # and restore_cpusets() will have trouble restoring the cpusets. # This is because of the rule that a child cpuset cannot have a cpu that # is not present in its parent cpuset. find $dir -mindepth 2 -name "cpuset.cpus" -type f -print | sort > saved_path.txt # Delete saved_path.txt if it is NULL val=`cat saved_path.txt` if [ -z "$val" ]; then rm -f saved_path.txt exit 0 fi for cpuset in `cat saved_path.txt` do cat $cpuset >> saved_cpusets.txt done paste saved_path.txt saved_cpusets.txt > temp.txt mv temp.txt saved_cpusets.txt rm -f saved_path.txt } restore_cpusets() { if [ ! -f saved_cpusets.txt ]; then # Nothing to be done exit 0 fi while read line do cpuset_path=`echo $line | cut -d' ' -f1` value=`echo $line | cut -d' ' -f2` echo "$value" > $cpuset_path done < saved_cpusets.txt rm -f saved_cpusets.txt } case "$1" in suspend|hibernate) save_cpusets ;; resume|thaw) restore_cpusets ;; *) ;; esac exit $?

On 04/17/2012 03:02 PM, Daniel P. Berrange wrote: Nice! Thanks :-) Regards, Srivatsa S. Bhat IBM Linux Technology Center