On 02/20/2012 01:24 AM, Zhang, Yang Z wrote: > Changes in v2: > Add UIP check logic. > Add logic that next second tick will occur in exactly 500ms later after setting the clock > > Current RTC emulation uses periodic timer(2 timers per second) to update RTC clock. And it will stop CPU staying at deep C-state for long period. Our experience shows the Pkg C6 residency reduced 6% when running 64 idle guest. > The following patch stop the two periodic timer and only updating RTC clock when guest try to read it. > > --- > Yang Zhang (4): > RTC: Update the RTC clock only when reading it > RTC: Add RTC update-ended interrupt support > RTC: Add alarm support > RTC: Add UIP(update in progress) check logic > > hw/mc146818rtc.c | 447 +++++++++++++++++++++++++++++++++++++----------------- > 1 files changed, 308 insertions(+), 139 deletions(-) > > best regards > yang > > -- > To unsubscribe from this list: send the line "unsubscribe kvm" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html > Thanks, this looks much better! I'll run it through some tests. We also should try to keep migration working from older versions using the load_old callback. Paolo -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
