Re: [libvirt] [PATCH 4/5] qemu: Build command line for NUMA tuning

于 2011年05月06日 17:23, Daniel P. Berrange 写道: >On Thu, May 05, 2011 at 04:30:30PM -0400, Bill Gray wrote: >> >>Hi Daniel, >> >>How can we get NUMA-aligned memory and CPUs if we apply binding APIs >>after the process has already started? Might not all the memory >>already be allocated on the wrong nodes by then? > >The policy has to be set after fork'ing the new QEMU process, but >before exec'ing QEMU. This is essentially what you're doing with >numactl, but with the problem of an extra binary that screws up >the SELinux domain transitions from libvirtd_t -> svirt_t. > >>For expert users, what are the problems with starting qemu with an >>external numactl command (with --cpunodebind and --membind) to >>guarantee optimal alignment? > >Adding an intermediate process will prevent the neccessary SELinux >domain transitions from working. We don't want to allow the >numactl binary to be able to transition to svirt_t because that >would be inappropriate for most users of numactl This make sense, as you said in another mail, perhaps we need to do some work on __virExec, will make v2 series. Thanks for feedback.