13 Dec
2012
13 Dec
'12
9:41 a.m.
On 12/13/12 08:01, Hu Tao wrote:
This is merely a rebased version, so still tagged with v1.
The reason to disable cgroup cpuset by default is: currently, sub-directories of cgroup cpuset won't be auto-updated if cpu hot-plug happens. For example, if we now have 0-3,5-7 pcpus online, the value of /sys/fs/cgroup/cpuset/libvirt/qemu/mydom/cpuset.cpus is 0-3,5-7, then pcpu 4 is hot-plugged, but the value of cpuset.cpus is still 0-3,5-7. This will cause a problem that we can't pin to a hot-plugged pcpu.
Users can still enable cpuset by editing qemu.conf.
CPU hotplug isn't really a common thing in hosts right now. I'd rather go for cpusets enabled by default and disabling them only if it poses problems. Peter