https://bugzilla.kernel.org/show_bug.cgi?id=16070 --- Comment #1 from Anonymous Emailer <anonymous@xxxxxxxxxxxxxxxxxxxx> 2010-05-28 15:20:51 --- Reply-To: dgilbert@xxxxxxxxxxxx On 10-05-28 10:55 AM, bugzilla-daemon@xxxxxxxxxxxxxxxxxxx wrote: > https://bugzilla.kernel.org/show_bug.cgi?id=16070 > > Summary: Fail to issue Start/Stop Unit > Product: IO/Storage > Version: 2.5 > Kernel Version: 2.6.34-rc5 > Platform: All > OS/Version: Linux > Tree: Mainline > Status: NEW > Severity: normal > Priority: P1 > Component: SCSI > AssignedTo: linux-scsi@xxxxxxxxxxxxxxx > ReportedBy: ian@xxxxxxxxxxxxxxxxxxxxx > Regression: No > > > I am attempting to save power by spinning down idle scsi disks. These are old > fashioned parallel (U320) disks on a SCSI storage controller: LSI Logic / > Symbios Logic 53c1030 PCI-X Fusion-MPT Dual Ultra320 SCSI (rev 07). > > I do: > > sg_start --stop /dev/sde > echo 0xfffffff> /sys/module/scsi_mod/parameters/scsi_logging_level > dd if=/dev/sde of=/dev/null count=1 > sleep 10 > echo 0> /sys/module/scsi_mod/parameters/scsi_logging_level > > I get: > dd: reading `/dev/sde': Input/output error > 0+0 records in > 0+0 records out > 0 bytes (0 B) copied, 0.00536828 s, 0.0 kB/s > > If I manually spin up the disk with sg_start --start /dev/sde, then things work > again as expected. <snip> > > After getting: "Add. Sense: Logical unit not ready, initializing command > required" I would expect a Start/Stop unit command, but it appears that none is > ever issued. There is a different design philosophy between SCSI and ATA disks (and has been for a very long time) reflecting their different markets. When a SCSI disk is spun down, then it will return errors on any command trying to do IO until a SCSI START STOP UNIT command (start) is sent and then time is allowed for the disk to spin up. What you report as a bug is the long standing behaviour of SCSI disks which Linux has not tried to modify. Doug Gilbert -- Configure bugmail: https://bugzilla.kernel.org/userprefs.cgi?tab=email ------- You are receiving this mail because: ------- You are the assignee for the bug. -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
