Re: [Qemu-devel] [PATCH v3 0/7] RTC: New logic to emulate RTC

[Paolo Bonzini]

Il 14/03/2012 09:52, Zhang, Yang Z ha scritto:
>>>>> Is there any comments with the version 3?
>>> 
>>> Can you explain why you dropped the logic to set the timer to the
>>> next event?
> Do you mean why I change the rtc logic? The reason is that: When a
> guest is idle, the main activity inside qemu is the rtc update
> timer(2 per second). In our experience(running 64 rhel6u1 guests), it
> will decrease pkg C6 residency about 6%(6% means 2 watts in my box).
> And normally, the guest will not use the update-end interrupt and
> alarm. So there has no need to run a periodic timer when guest isn't
> using it.

No, why you're keeping roughly the same logic as current QEMU, instead
of the more radical changes that were in v2.

Paolo