* Vivek Goyal <vgoyal@xxxxxxxxxx> [2010-07-22 17:26:34]: > On Thu, Jul 22, 2010 at 02:18:56PM -0700, Greg KH wrote: > > On Thu, Jul 22, 2010 at 03:37:41PM -0400, Vivek Goyal wrote: > > > On Thu, Jul 22, 2010 at 11:36:15AM -0700, Greg KH wrote: > > > > On Thu, Jul 22, 2010 at 11:31:07AM -0700, Paul Menage wrote: > > > > > On Thu, Jul 22, 2010 at 11:26 AM, Greg KH <gregkh@xxxxxxx> wrote: > > > > > > We really shouldn't be asking userspace to create new root filesystems. > > > > > > So follow along with all of the other in-kernel filesystems, and provide > > > > > > a mount point in sysfs. > > > > > > > > > > > > For cgroupfs, this should be in /sys/fs/cgroup/ This change provides > > > > > > that mount point when the cgroup filesystem is registered in the kernel. > > > > > > > > > > But cgroups will typically have multiple mounts, with different > > > > > resource controllers/options on each mount. That doesn't really fit in > > > > > with this scheme. > > > > > > > > Really? I see systems mounting it at /cgroups/ in the filesystem today. > > > > Where are you expecting it to be mounted at? > > > > > > > > > > Greg, > > > > > > [CCing few more folks who might be interested in this dicussion ] > > > > > > We do want to retain facility to mount different controllers at different > > > mount points. We were discussing the other day that in libvirt we might > > > want to mount block IO controller and network controller separately as > > > by default we will not put a new virtual machine in a cgroup of its own > > > because of the penatly involved. > > > > That's fine, I'm not changing that ability at all. We just need a > > "default" mount point for "normal" users. > > > > > For other controllers like cpu, memory etc, libvirt automatically puts > > > each new virtual machine in a cgroup of own. So this is one use case > > > where we might want to mount different controllers at different mount > > > points. > > > > > > For my testing I now always use /cgroup/ and create directories under it > > > /cgroup/blkio /cgroup/cpu etc and mount controllers on respective > > > directories. > > > > Lennart and Kay, is this what systemd is doing? I really don't think we > > should be adding a root /cgroup/ mount point to the system for something > > like this. > > > > Maybe /dev/cgroup/ is better to use, as that way users can create > > sub-mount points easier. They can't do that in /sys/fs/cgroup/ > > The only problem with /dev/cgroup seems to be that it seems little > unintutive. To me, we have devices under /dev/ dir and cgroups are not > devices. > > I think people have floated similar threads in the past on lkml with > various opinions and everybody had their own choices but nothing was > conclusive. > > Polluting / definitely sounds odd but it does not look that bad once > we can't find any other good choices. > I think it breaks the filesystem hierarchy standard and I've seen bugzilla's around it. I'd prefer /sys/fs/cgroup. -- Three Cheers, Balbir _______________________________________________ Containers mailing list Containers@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/containers
