Anthony Liguori wrote: > Glauber Costa wrote: >> Hi guys, >> >> Here's a first series of patch aiming at vcpu pinning support in qemu. >> Ideally, as vcpu as just normal threads, the usual userspace tools can >> be used >> to set cpu affinities mask. >> >> However, It makes it very difficult to _start_ a vm with vcpus pinned, >> since >> we don't know the thread ids from qemu in advance, nor do we know when >> are the >> vcpus created. >> >> The patches introduce a -cpu-map option, that, if specified, starts >> the virtual cpus >> with the specified affinities. >> >> Comments? Welcome. Random rants? Not welcome, but... how can I stop >> you? So go ahead! >> >> > > So why exactly is this useful? I have a hard time constructing a > reasonable use-case in my mind for something like this.
My main interest is in management tools being able to specify pinning set ups at VM creation time. As I said, it can be done through tools like taskset, but then you'd have to know: * when are the threads created * which thread ids corresponds to each cpu And of course, for an amount of time, the threads will be running in a "wrong" cpu, which may affect workloads running there. (which is a case cpu pinning usually tries to address) ------------------------------------------------------------------------- This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2008. http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ _______________________________________________ kvm-devel mailing list kvm-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/kvm-devel
