Re: [rfc] "laptop mode"

[Daniel Jacobowitz]

On Wed, Jun 05, 2002 at 01:07:35PM -0400, Andrew Pimlott wrote:
> On Tue, Jun 04, 2002 at 11:41:57PM -0400, Albert D. Cahalan wrote:
> > Also write out everything just before stopping the disk.
> > Don't let the disk stop if there is any dirty data.
> 
> The kernel doesn't currently do spin-down at all, does it?  Andrew,
> are you planning to change this?  I'm not a kernel programmer, but
> it seems like a good idea to me:  The kernel could flush writes as
> usual while the disk is spun up, but still spin down after a bit if
> the rate is low enough.  The disk would never spin itself down in
> that case.  Maybe there are also cases where the kernel would delay
> spin-down, if it hasn't started writing but thinks it might soon.
> 
> I'm excited to try this.  Thanks for writing it against 2.4!

At that point, you might as well be in userspace - particularly, you
might as well be running/enhancing noflushd.

-- 
Daniel Jacobowitz                           Carnegie Mellon University
MontaVista Software                         Debian GNU/Linux Developer