Spun-down hard disk being spun-up just before poweroff

Question

Hi folks,
I have two SATA disks attached to my computer, one of them is my main disk and the other one is a backup disk I bought some weeks ago. That second disk is used just once a day, so I spin-down it on boot time with sdparm, being very careful about not frequently spininng-up the hard disk.
So everything is all right until I decide to shutdown my computer: just before the "POWER OFF" text appears on screen, the second hard disk spins-up and two seconds later my computer power offs. That means an extra spin-up for my hard disk, and I would like to avoid it.
I have studied /etc/rc.shutdown, and I think I have found the reason which causes this to happen. From /etc/rc.shutdown:
/sbin/poweroff -d -f -h -i
The -h flag puts all hard drives in standby mode, so my hard disk spins-up on that moment.
Has anyone managed to keep spinned-down disks just that way? Is there any way to tell poweroff not to put spun-down hard disk in standby?
Thank you very much.
Last edited by panecillo (2008-12-26 19:14:34)

Answer 1

Hi,
The problem is that newer kernels send a flush and standby and some disk spun up, then "clack" sound. This is not funny.
A msg from kernel will be appear when this occurrs
} else {
/* XXX: This is for backward compatibility, will be
* removed. Read Documentation/feature-removal-schedule.txt
* for more info.
if ((qc->dev->flags & ATA_DFLAG_SPUNDOWN) &&
(system_state == SYSTEM_HALT ||
system_state == SYSTEM_POWER_OFF)) {
static unsigned long warned;
if (!test_and_set_bit(0, &warned)) {
ata_dev_printk(qc->dev, KERN_WARNING,
"DISK MIGHT NOT BE SPUN DOWN PROPERLY. "
"UPDATE SHUTDOWN UTILITY\n");
ata_dev_printk(qc->dev, KERN_WARNING,
"For more info, visit "
"http://linux-ata.org/shutdown.html\n");
/* ->scsi_done is not used, use it for
* delayed completion.
scmd->scsi_done = qc->scsidone;
qc->scsidone = ata_delayed_done;
scmd->result = SAM_STAT_GOOD;
return 1;
/* Issue ATA STANDBY IMMEDIATE command */
tf->command = ATA_CMD_STANDBYNOW1;
This line is bad, -h flag not needed on newer kernels since libata send a FLUSH_CACHE and STANDBYNOW.
Try remove the -h flag, but this is for IDE disk only.
More info at http://linux-ata.org/shutdown.html
I will create a ticket in the bugtracker.
Good Bye, Good Year
Last edited by djgera (2008-12-31 23:08:22)