Hi,
the usage profile of my NAS is such that I could send all drives to sleep overnight to save some euros on power consumption. For testing purposes, I therefore added the command
/sbin/camcontrol sleep ada0
or, with identical function,
/usr/local/sbin/ataidle -o /dev/ada0
to be executed by cron at 3:10 a.m.
I then automatically checked the power state of the drive every minute
smartctl -n standby /dev/ada0
The result shows that the drive is forced to sleep but gets woken up soon from SLEEP to STANDBY mode:
...
Sun Dec 18 03:09:21 CET 2011: ACTIVE or IDLE mode
Sun Dec 18 03:10:21 CET 2011: SLEEP mode, exit(2)
Sun Dec 18 03:11:41 CET 2011: STANDBY mode, exit(2)
...
Why is this and how can it be prevented. There is no disk access from clients for sure.
Merry Christmas!
Boris
the usage profile of my NAS is such that I could send all drives to sleep overnight to save some euros on power consumption. For testing purposes, I therefore added the command
/sbin/camcontrol sleep ada0
or, with identical function,
/usr/local/sbin/ataidle -o /dev/ada0
to be executed by cron at 3:10 a.m.
I then automatically checked the power state of the drive every minute
smartctl -n standby /dev/ada0
The result shows that the drive is forced to sleep but gets woken up soon from SLEEP to STANDBY mode:
...
Sun Dec 18 03:09:21 CET 2011: ACTIVE or IDLE mode
Sun Dec 18 03:10:21 CET 2011: SLEEP mode, exit(2)
Sun Dec 18 03:11:41 CET 2011: STANDBY mode, exit(2)
...
Why is this and how can it be prevented. There is no disk access from clients for sure.
Merry Christmas!
Boris
