graid often resyncs raid1 array after clean reboot/shutdown

[Alexander Motin]

On 29.10.2012 10:29, Alexander Motin wrote:
> Hi.
>
> On 29.10.2012 06:55, Lawrence Stewart wrote:
>> I have a fairly new HP Compaq 8200 Elite desktop PC with 2 x 1TB Seagate
>> ST1000DM003 HDDs in raid1 using the on-board Intel Matrix RAID
>> controller. The system is configured to boot from ZFS off the raid1
>> array, and I use it as a KDE GUI (with on-cpu GPU + KMS) desktop.
>>
>> Everything works great, except that after a "shutdown -r now" of the
>> system, graid almost always (I believe I've noted a few times where
>> everything comes up fine) detects one of the disks in the array as stale
>> and does a full resync of the array over the course of a few hours.
>> Here's an example of what I see when starting up:
>
>  From log messages it indeed looks like result of unclean shutdown. I've
> never seen such problem with UFS, but I never tested graid with ZFS. I
> guess there may be some difference in shutdown process that makes RAID
> metadata to have dirty flag on reboot. I'll try to reproduce it now.

I confirm the problem. Seems it happens only when using ZFS as root file 
system. Probably ZFS issues some last moment write that makes volume 
dirty. I will trace it more.

-- 
Alexander Motin