kern/133593: [ata] `atacontrol spindown` won't affect disk until some data is read from it

[Dmitry Marakasov]

>Number:         133593
>Category:       kern
>Synopsis:       [ata] `atacontrol spindown` won't affect disk until some data is read from it
>Confidential:   no
>Severity:       non-critical
>Priority:       low
>Responsible:    freebsd-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Sat Apr 11 03:00:12 UTC 2009
>Closed-Date:
>Last-Modified:
>Originator:     Dmitry Marakasov
>Release:        FreeBSD 8.0-CURRENT i386
>Organization:
>Environment:
System: FreeBSD hades.panopticon 8.0-CURRENT FreeBSD 8.0-CURRENT #0: Thu Apr 9 02:46:37 MSD 2009 root at hades.panopticon:/async/obj/usr/src/sys/HADES i386


>Description:
I have and extra PATA drive that I use for backups, and it is not even mounted on boot. To make it sleep until needed I've added atacontrol spindown ad5 60 into /etc/rc.local, but it turned out that this won't affect the drive until it is touched in any way. For example, if I do `dd if=/dev/ad5 of=/dev/null bs=512 count=1`, drive will spindown in 60 as it should. If I add it to fstab, it's also spun down. But until it is touched, it wont.

% sudo atacontrol info ata2
Master:  ad4 <ST3300622A/3.AAH> ATA/ATAPI revision 7
Slave:   ad5 <ST3300622A/3.AAH> ATA/ATAPI revision 7

% dmesg | grep ata2
ata2: <ATA channel 0> on atapci0
ata2: [ITHREAD]
ad4: 286168MB <Seagate ST3300622A 3.AAH> at ata2-master UDMA100
ad5: 286168MB <Seagate ST3300622A 3.AAH> at ata2-slave UDMA100

% dmesg | grep atapci0
atapci0: <Marvell 88SX6121 UDMA133 controller> port 0xec00-0xec07,0xe880-0xe883,0xe800-0xe807,0xe480-0xe483,0xe400-0xe40f mem 0xfeaffc00-0xfeafffff irq 16 at device 0.0 on pci3
atapci0: [ITHREAD]
ata2: <ATA channel 0> on atapci0

>How-To-Repeat:
>Fix:

>Release-Note:
>Audit-Trail:
>Unformatted: