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

[Zhang, Yang Z]

> -----Original Message-----
> From: Paolo Bonzini [mailto:address@hidden
> Sent: Wednesday, March 14, 2012 4:35 PM
> To: Zhang, Yang Z
> Cc: address@hidden; Jan Kiszka; address@hidden;
> address@hidden; Marcelo Tosatti
> Subject: Re: [PATCH v3 0/7] RTC: New logic to emulate RTC
> 
> Il 14/03/2012 01:00, 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. 

best regards
yang