Re: [PATCH 0/2] range timer support

[Keir Fraser <keir.fraser@eu.citrix.com>]

On 28/10/08 06:57, "Yu, Ke" <ke.yu@intel.com> wrote:

> The major changes are:
> - rebase with latest upstream: sync with the timer link list chagne (changeset
> 18381), sync with the heap memory allocation change (changeset 18671)
> - Per Keir's comment, more usage is found: use the range timer in HVM virtual
> periodic timer (xen/arch/x86/hvm/vpt.c). Since vpt has the logic to handle
> missing ticks, it is an ideal place to use range timer.
> - the original deferrable timer is renamed to range timer, to better describe
> the conecpt. This renaming is inspired by a similar proposal in linux kernel
> community (http://kerneltrap.org/mailarchive/linux-kernel/2008/9/1/3160404)
> 
> A preliminary measurement is done in a dual core mobile platform (Montivina).
> When creating 4 RHEL5 HVM UP guests, the range timer patch can reduce ~5%
> power consumption. More measurement is onging. This post is inteneded to get
> more feedback to refine it.

You'll have to explain how the implementation in timer.c works. I'm not sure
I believe it really does.

 -- Keir