On Thu, 2020-04-09 at 16:45 -0300, Daniel Henrique Barboza wrote: > In a guest with only one vcpu, when pinning the emulator in say CPU184 > and the vcpu0 in CPU0 of the host, the user might expect that only > CPU0 and CPU184 of the host will be used by the guest. > > The reality is that Libvirt takes some time to honor the emulator > and vcpu pinning, taking care of NUMA constraints first. This will > result in other CPUs of the host being potentially used by the > QEMU thread until the emulator/vcpu pinning is done. The user > then might be confused by the output of 'virsh cpu-stats' in this > scenario, showing around 200 microseconds of cycles being spent > in other CPUs. > > Let's document this behavior, which is explained in detail in > Libvirt commit v5.0.0-199-gf136b83139, in the cputune section > of formatdomain.html.in. > > Signed-off-by: Daniel Henrique Barboza <danielhb413@xxxxxxxxx> > --- > docs/formatdomain.html.in | 7 +++++++ > 1 file changed, 7 insertions(+) Reviewed-by: Andrea Bolognani <abologna@xxxxxxxxxx> and pushed. -- Andrea Bolognani / Red Hat / Virtualization
