> I've got an array (on kubuntu 14.10) with 5 WD-RED drives and > would like them to stop rotating when there is no access for > 10 minutes. I used hdparm -S 120 That works here for 6 disks on which I have created various types of MD sets for holding data or for testing. # cat /proc/mdstat Personalities : [raid6] [raid5] [raid4] [raid10] [linear] [multipath] [raid0] [raid1] md1 : active raid10 sde3[6] sdd3[4] sdb3[0] sdc3[5] 486538976 blocks super 1.0 16K chunks 2 near-copies [4/4] [UUUU] md4 : active raid6 sde4[3] sdb4[0] sdg4[7] sdd4[2] sdf4[6] sdc4[1] 973077760 blocks super 1.0 level 6, 64k chunk, algorithm 2 [6/6] [UUUUUU] md2 : active raid5 sde2[2] sdg2[5] sdf2[3] sdc2[0] sdd2[1] 486538752 blocks super 1.0 level 5, 64k chunk, algorithm 2 [5/5] [UUUUU] md0 : active raid10 sde1[3] sdb1[0] sdg1[5] sdf1[4] sdc1[1] sdd1[2] 364904208 blocks super 1.0 16K chunks 2 near-copies [6/6] [UUUUUU] unused devices: <none> # hddtemp /dev/sd[bcdef] /dev/sdb: SAMSUNG HD103UJ: drive is sleeping /dev/sdc: WDC WD10EZEX-22RKKA0: drive is sleeping /dev/sdd: ST1000DM003-9YN162: drive is sleeping /dev/sde: SAMSUNG HD103SJ: drive is sleeping /dev/sdf: WDC WD10EZEX-22RKKA0: drive is sleeping > for all of them but they keep on running. [ ... ] That means something else is waking up those disks. To verify this use something like: sudo iostat -dkxz 1 or use something like: sudo sysctl vm/block_dump=1; sleep 120; sudo sysctl vm/block_dump=0 and then look at the debug log to see which inodes get hit. -- To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
