[libvirt] [PATCH 0/3] qemu: support -overcommit cpu-pm=on|off

Menno Lageman menno.lageman at oracle.com
Mon Aug 19 08:32:23 UTC 2019


QEMU introduced a CPU power management feature with commit 6f131f13e68d
("kvm: support -overcommit cpu-pm=on|off").

With this flag, kvm allows guest to control host CPU power state.  This
increases latency for other processes using same host CPU in an
unpredictable way, but if decreases idle entry/exit times for the
running VCPU, so to use it QEMU needs a hint about whether host CPU is
overcommitted, hence the flag name.

This patch series adds a new kvm feature 'cpu-pm' for controlling
"-overcommit cpu-pm=[on|off]"

    <features>
      <kvm>
        <cpu-pm state='on'/>
      </kvm>
    </features>


Menno Lageman (2):
  qemu: introduce qemuBuildOvercommitCommandLine()
  tests: add tests for cpu-pm feature

Wim ten Have (1):
  qemu: add hypervisor feature cpu-pm support for kvm

 docs/formatdomain.html.in                     |  7 ++++
 docs/schemas/domaincommon.rng                 |  5 +++
 src/conf/domain_conf.c                        |  4 ++
 src/conf/domain_conf.h                        |  1 +
 src/libvirt_private.syms                      |  1 +
 src/qemu/qemu_command.c                       | 39 +++++++++++++++++--
 src/qemu/qemu_domain.c                        | 25 ++++++++----
 tests/qemuxml2argvdata/kvm-features-off.args  |  2 +-
 tests/qemuxml2argvdata/kvm-features-off.xml   |  1 +
 tests/qemuxml2argvdata/kvm-features.args      |  2 +-
 tests/qemuxml2argvdata/kvm-features.xml       |  1 +
 tests/qemuxml2argvtest.c                      |  4 +-
 tests/qemuxml2xmloutdata/kvm-features-off.xml |  1 +
 tests/qemuxml2xmloutdata/kvm-features.xml     |  1 +
 14 files changed, 79 insertions(+), 15 deletions(-)

-- 
2.21.0




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