On Fri, 2 Feb 2018 16:49:54 -0500 Luiz Capitulino <lcapitulino@xxxxxxxxxx> wrote: > On Fri, 2 Feb 2018 18:41:44 -0200 > Eduardo Habkost <ehabkost@xxxxxxxxxx> wrote: > > > On Fri, Feb 02, 2018 at 03:19:45PM -0500, Luiz Capitulino wrote: > > > On Fri, 2 Feb 2018 18:09:12 -0200 > > > Eduardo Habkost <ehabkost@xxxxxxxxxx> wrote: > > [...] > > > > Your plan above covers what will happen when using newer QEMU > > > > versions, but libvirt still needs to work sanely if running QEMU > > > > 2.11. My suggestion is that libvirt do not run query-cpus to ask > > > > for the "halted" field on any architecture except s390. > > > > > > My current plan is to ask libvirt to completely remove query-cpus > > > usage, independent of the arch and use the new command instead. > > > > This would be a regression for people running QEMU 2.11 on s390. > > libvirt could use query-cpus on s390 if the new command is not > available. Btw, even on s390 query-cpus runs run_on_cpu(), which is what causes vCPUs to go to user-space. So, s390 should suffer the same performance problem. Pick your regression. > > > > > (But maybe it would be an acceptable regression? Viktor, what do > > you think? Are there production releases of management systems > > that already rely on vcpu.<n>.halted?) > > >
