zfs discuss - Apr 2010 - Is it safe/possible to idle HD''s in a ZFS Vdev to save wear/power?

Hi all,

I''m still an OpenSolaris noob, so please be gentle...

I was just wondering if it is possible to spindown/idle/sleep hard disks that
are part of a Vdev & pool SAFELY?

My objective is to sleep the drives after X time when they''re not being
used and spin them back up if required.  This is for a home system, so
I''m not fussed by a minor delay before data is accessible again.

I realise it''s not applicable, in the Linux world this is possible
using hdparm on mdadm devices, but I can''t find any info on doing
similar in OpenSolaris safely or otherwise.

Could anyone shed some light here?
-- 
This message posted from opensolaris.org

On 04/16/10 20:26, Joe wrote:
> I was just wondering if it is possible to spindown/idle/sleep hard disks
that are part of a Vdev&  pool SAFELY?
it''s possible.

my ultra24 desktop has this enabled by default (because it''s a known 
desktop type).  see the power.conf man page; I think you may need to add 
an "autopm enable" if the system isn''t recognized as a known
desktop.

the disks spin down when the system is idle; there''s a delay of a few 
seconds when they spin back up.

					- Bill

Hi.

I''m using two SIIG eSATA II PCIe PRO adapters on a Sun Ultra 24
workstation, too. The adapters are connected to four external eSATA
drives that made up a zpool used for scheduled back-up purposes. I''m
now running SXCE b129, live upgraded from b116. Before the live
upgrade the external disks were spinning down when idle, now they
never do. /etc/power.conf was not modified. I''m probably waiting the
next OpenSolaris release and check if it works. Nevertheless, in the
meanwhile, do you have any suggestion about how to debug this? I don''t
like wasting energy this way and I cannot shutdown that machine so
often.

Thanks,
Enrico

On Sat, Apr 17, 2010 at 8:43 AM, Bill Sommerfeld
<bill.sommerfeld at oracle.com> wrote:
> On 04/16/10 20:26, Joe wrote:
>>
>> I was just wondering if it is possible to spindown/idle/sleep hard
disks
>> that are part of a Vdev& ?pool SAFELY?
>
> it''s possible.
>
> my ultra24 desktop has this enabled by default (because it''s a
known desktop
> type). ?see the power.conf man page; I think you may need to add an
"autopm
> enable" if the system isn''t recognized as a known desktop.
>
> the disks spin down when the system is idle; there''s a delay of a
few
> seconds when they spin back up.
>
> ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?- Bill
> _______________________________________________
> zfs-discuss mailing list
> zfs-discuss at opensolaris.org
> http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
>


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