On Fri, Jun 05, 2009 at 01:53:15AM -0700, Paul Menage wrote: > On Wed, Jun 3, 2009 at 10:36 PM, Bharata B > Rao<bharata@xxxxxxxxxxxxxxxxxx> wrote: > > - Hard limits can be used to provide guarantees. > > > > This claim (and the subsequent long thread it generated on how limits > can provide guarantees) confused me a bit. > > Why do we need limits to provide guarantees when we can already > provide guarantees via shares? shares design is proportional and hence it can't by itself provide guarantees. > > Suppose 10 cgroups each want 10% of the machine's CPU. We can just > give each cgroup an equal share, and they're guaranteed 10% if they > try to use it; if they don't use it, other cgroups can get access to > the idle cycles. Now if 11th group with same shares comes in, then each group will now get 9% of CPU and that 10% guarantee breaks. Regards, Bharata. -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
