On 12.02.2018 13:14, Viktor Mihajlovski wrote: > From: Luiz Capitulino <lcapitul...@redhat.com> > > The query-cpus command has an extremely serious side effect: > it always interrupts all running vCPUs so that they can run > ioctl calls. This can cause a huge performance degradation for > some workloads. And most of the information retrieved by the > ioctl calls are not even used by query-cpus. > > This commit introduces a replacement for query-cpus called > query-cpus-fast, which has the following features: > > o Never interrupt vCPUs threads. query-cpus-fast only returns > vCPU information maintained by QEMU itself, which should be > sufficient for most management software needs > > o Make "halted" field optional: we only return it if the > halted state is maintained by QEMU. But this also gives > the option of dropping the field in the future (see below) >
If I'm not wrong, this comment is superseded by ... > o Drop irrelevant fields such as "current", "pc" and "arch" > > o Drop field "halted" since it can't be provided fast reliably > and is too volatile on most architectures to be really useful > this comment :) > o Rename some fields for better clarification & proper naming > standard> > Signed-off-by: Luiz Capitulino <lcapitul...@redhat.com> > Signed-off-by: Viktor Mihajlovski <mihaj...@linux.vnet.ibm.com> Wondering if we could tweak the old interface with a simple flag "fast = true". -- Thanks, David / dhildenb
