On Fri, Feb 26, 2010 at 10:17:32AM +0100, Ingo Molnar wrote: > My suggestion, as always, would be to start very simple and very minimal: > > Enable 'perf kvm top' to show guest overhead. Use the exact same kernel image > both as a host and as guest (for testing), to not have to deal with the symbol > space transport problem initially. Enable 'perf kvm record' to only record > guest events by default. Etc. > > This alone will be a quite useful result already - and gives a basis for > further work. No need to spend months to do the big grand design straight > away, all of this can be done gradually and in the order of usefulness - and > you'll always have something that actually works (and helps your other KVM > projects) along the way. > > [ And, as so often, once you walk that path, that grand scheme you are > thinking about right now might easily become last year's really bad idea ;-) ] > > So please start walking the path and experience the challenges first-hand. That sounds like a good approach for the 'measure-guest-from-host' problem. It is also not very hard to implement. Where does perf fetch the rip of the nmi from, stack only or is this configurable? Joerg -- 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
