On Wed, Apr 15, 2015 at 05:10:49PM +0530, Preeti U Murthy wrote: > On 04/13/2015 08:13 PM, Peter Zijlstra wrote: > > On Mon, Apr 13, 2015 at 05:46:37PM +0530, Preeti U Murthy wrote: > >> On 04/13/2015 12:31 PM, Peter Zijlstra wrote: > > > >>> Would it not make sense to make that a mount option and limit the amount > >>> of semantic variants of cpusets? > >> > >> I spent some time analyzing if this would be a better option than the > >> sysfs knob and I think not for the following reasons: > >> > >> 1. Mount options tend to be generic across the controllers of a cgroup. > >> But use case addressed by this patch is specific to the cpuset controller. > > > > Surely we can get around that somehow. > > > >> 2. The behavior that this patch is trying to bring about is not a > >> drastic one to call for a mount option equivalent to the __SANE_BEHAVIOR > >> one that existed earlier. This option was used to switch the legacy > >> design to the default one. > >> > >> However this patch is not *wholly* mimicking the default hierarchy > >> behavior. The behavior when cpusets become empty is left untouched for > >> instance. The patch borrows one of the behaviors from the default > >> hierarchy only and hence just not justify the use of a mount flag. > > > > So the 'problem' I have is that you introduce a 3rd semantic for the > > cpuset thing. > > > > You also do not answer if you can live with the default hierarchy > > behaviour, only that your patch mimicks a subset of it. > > > > Why not all of it? > > This was assuming that the existing software will break if we mimick the > entire design given that we were informed that it does not work well > with the default hierarchy. But I think now, that its worth finding out > why if so and switch over to the new design, atleast for cpusets. Peter, is the question "why can't we just use the unified hierarchy for cpusets"? -- To unsubscribe from this list: send the line "unsubscribe cgroups" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
