2009/310 Disk IO PM Enhancement 1999/388 2005/250 2008/465

[David J. Brown]

James Carlson wrote:
> Terry Whatley writes:
>   
>> 	The IO framework and driver stack will be enhanced to provide generic
>> 	support of modern disks' power management capabilities.  The new
>> 	features include support of SPC-4/SBC-3 compliant disk power conditions.
>> 	The SATA framework will be enhanced to provide comparable software
>> 	translation between ATA power conditions and SBC-3 power conditions.
>>     
>
> Where's the rest of this project?  I would expect that, in order to
> finish this project, there's some work necessary to make the power
> management subsystem consume this data.  That doesn't appear to be a
> part of this project, though.
>
> Are the folks responsible for supporting autopm and the rest of the
> power management subsystem involved with this project?
>
> If not, are they aware of what this project is planning to deliver,
> and do they agree that the information will be usable to make power
> management decisions?
>
> If so, is there a future project ("autopm disk enhancements") that is
> dependent on this one?
>
> Help us to connect the dots from the set of low-level driver
> properties described here to the higher-level goal of providing better
> disk management.
>
>   
Terry,
    Isn't ZFS the primary consumer of these new PM-related disk driver 
properties [interfaces] at present?

Is there a design document that describes these new conceptions for 
storage-related power management?  Seems like that would help provide 
the context whereby folks could understand this a bit better.

It would also be very useful to have that around in the case's materials 
directory for anyone who came there later, wishing to learn about this.

-db

-- 
; David J. Brown Ph.D. (cantab.)
; Solaris Engineering
; Sun Microsystems Inc. 
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