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Date: Thu, 27 May 2010 20:18:49 +0200 (CEST)
From: Thomas Gleixner <tglx@linutronix.de>
To: Matthew Garrett <mjg59@srcf.ucam.org>
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Subject: Re: [linux-pm] [PATCH 0/8] Suspend block api (version 8)
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On Thu, 27 May 2010, Matthew Garrett wrote:

> On Thu, May 27, 2010 at 06:49:18PM +0100, Alan Cox wrote:
> > > ACPI provides no guarantees about what level of hardware functionality 
> > > remains during S3. You don't have any useful ability to determine which 
> > > events will generate wakeups. And from a purely practical point of view, 
> > > since the latency is in the range of seconds, you'll never have a low 
> > > enough wakeup rate to hit it.
> > 
> > So PCs with current ACPI don't get opportunistic suspend capability. It
> > probably won't be supported on the Commodore Amiga either - your point ?
> 
> Actually, the reverse - there's no terribly good way to make PCs work 
> with scheduler-based suspend, but there's no reason why they wouldn't 
> work with the current opportunistic suspend implementation.

How does that solve the problems you mentioned above ? Wakeup
guarantees, latencies ...

It's not a prove of the technical correctness of the approach if it
can provide a useless functionality.
 
Thanks,

	tglx