> > The problem with this is that it requires an administrator to understand the > workload, not only of the guest, but also of other guests on the machine. > With low overcommit, a high PLE window reduces unneeded exits, but with > high overcommit we need those exits to reduce spinning. > > In addition, most kvm hosts don't have an administrator. They are controlled > by a management system, which means we'll need some algorithm in > userspace to control the PLE window. Taking the two together, we need a > dynamic (for changing workloads) algorithm. > > There are threads discussing this dynamic algorithm, we are making slow > progress because it's such a difficult problem, but I think this is much more > useful than anything requiring user intervention. Avi, agreed that dynamic adaptive ple should be the best solution. However currently it is a difficult problem like you said. Our solution just gives user a choice who know how to set the two PLE values. So the solution is a compromise solution, which should be better than nothing, for now? :-) Your comments? -- 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
