From mboxrd@z Thu Jan  1 00:00:00 1970
From: Samuel Thibault <samuel.thibault@eu.citrix.com>
Subject: Re: [RFC] PVFB: Add refresh period to XenStore parameters?
Date: Mon, 5 May 2008 11:21:07 +0100
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To: Markus Armbruster <armbru@redhat.com>
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Markus Armbruster, le Mon 05 May 2008 11:58:53 +0200, a écrit :
> >> Other than that, the change seems to affect only Mini-OS and
> >> CONFIG_STUBDOM, which are both outside the area of my expertise (and
> >> frankly, interest).
> >
> > Well, that could be used in the linux frontend to disable the timer too.
> > That may interest e.g. laptop users.
> 
> The frontend should not send any events unless something's drawing on
> the display.

Agreed.

> And when something's drawing on the display, the guest,
> and therefore the laptop, is already burning processor cycles,

Agreed.

> and whether disabling sending updates saves any battery power is not
> obvious.

Disabling _sending_ updates does not, yes.

> Of course, if you can demonstrate it does...

Disabling _having to care_ whether some updates should be sent _do_ save
battery.  Now, contrary to what I thought, it happens that linux' xenfb
is not using a periodic timer but a triggered timer, so it does not in
that case indeed.

Samuel