On Mon, Feb 06, 2017 at 01:33:09PM -0200, Marcelo Tosatti wrote: > On Mon, Feb 06, 2017 at 10:23:35AM +0800, Eli Qiao wrote: > > This series patches are for supportting CAT featues, which also > > called cache tune in libvirt. > > > > First to expose cache information which could be tuned in capabilites XML. > > Then add new domain xml element support to add cacahe bank which will apply > > on this libvirt domain. > > > > This series patches add a util file `resctrl.c/h`, an interface to talk with > > linux kernel's sys fs. > > > > There are still some TODOs such as expose new public interface to get free > > cache information. > > > > Some discussion about this feature support can be found from: > > https://www.redhat.com/archives/libvir-list/2017-January/msg00644.html > > Two comments: > > 1) Please perform appropriate filesystem locking when accessing > resctrlfs, as described at: > > http://www.spinics.net/lists/linux-tip-commits/msg36754.html > > 2) > > <cachetune id='10' host_id='1' type='l3' size='3072' unit='KiB'/> > > [b4c270b5-e0f9-4106-a446-69032872ed7d]# cat tasks > 8654 > [b4c270b5-e0f9-4106-a446-69032872ed7d]# pstree -p | grep qemu > |-qemu-kvm(8654)-+-{qemu-kvm}(8688) > | |-{qemu-kvm}(8692) > | `-{qemu-kvm}(8693) > > Should add individual vcpus to the "tasks" file, not the main QEMU > process. > > The NFV usecase requires exclusive CAT allocation for the vcpu which > runs the sensitive workload. > > Perhaps: > > <cachetune id='10' host_id='1' type='l3' size='3072' unit='KiB'/> > > Adds all vcpus that are pinned to the socket which cachebank with > host_id=1. > > <cachetune id='10' host_id='1' type='l3' size='3072' unit='KiB' vcpus=2,3/> > > Adds PID of vcpus 2 and 3 to resctrl directory created for this > allocation. 3) CDP / non-CDP convertion. In case the size determination has been performed with non-CDP, to emulate such allocation on a CDP host, it would be good to allow both code and data allocations to share the CBM space: <cachetune id='10' host_id='1' type='l3data' size='3072' unit='KiB'/> <cachetune id='10' host_id='1' type='l3code' size='3072' unit='KiB'/> Perhaps if using the same ID? Other than that, testing looks good. -- libvir-list mailing list libvir-list@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/libvir-list
