Hi, I use "lvm2 on software raid" on an opteron fileserver. The machine is running the amd64 port but I don't think that is part of the problem. I am simply wondering if anyone else has noticed that since it sounds like a bug to me (as in bug vs feature). Here is the setup: kernel: Linux dax 2.6.15.4 (custom built) > cat /proc/mdstat Personalities : [raid1] md0 : active raid1 sda1[0] sdc1[2](S) sdb1[1] 96256 blocks [2/2] [UU] md1 : active raid1 sda2[0] sdc2[2](S) sdb2[1] 156143680 blocks [2/2] [UU] md0 is the boot partition while md1 is the only lvm physical volume. sdc is only used as a spare disk. sdd is a unit from an hardware raid controller, it does not matter for the current problem. The odd thing looks like that: > iostat 1 ... avg-cpu: %user %nice %sys %iowait %idle 0.00 0.00 0.00 0.00 100.00 Device: tps Blk_read/s Blk_wrtn/s Blk_read Blk_wrtn sda 3.00 0.00 144.00 0 144 sdb 3.00 0.00 144.00 0 144 sdc 2.00 0.00 16.00 0 16 md1 1.00 0.00 128.00 0 128 sdd 7.00 0.00 80.00 0 80 md0 0.00 0.00 0.00 0 0 ... As you can see there is a write to the spare disk (sdc). That is not much, so I guess that this is only the event counter being updated. But in my opinion, this is a problem. Why is this a problem? In this system, I do not expect a continous use of the system drives, therefore I will see a start/stop cycle a few times a day. This is fine but I bet that the motor will be the first thing to fail on those drive, which is why I would like the hot spare to be there. Now, if an event counter is incremented, the spare will also spin up/spin down, and so likely break around the same time as the others. My problem is then that I don't understand why a event counter is needed on a spare disk, it is not supposed to be used unless something goes wrong... Did I miss something? thanks jacques PS: I know that a quick work around would be to completely disable the spin down timer on every drive, but that is only hidding the dust below the carpet.
Attachment:
signature.asc
Description: Digital signature