Do we want a periodic script for a zfs scrub?

[Alexander Leidinger]

Quoting Bernd Walter <ticso at cicely7.cicely.de> (from Wed, 9 Jun 2010  
16:43:55 +0200):

> On Wed, Jun 09, 2010 at 04:26:27PM +0200, Alexander Leidinger wrote:
>> Hi,
>>
>> I noticed that we do not have an automatism to scrub a ZFS pool
>> periodically. Is there interest in something like this, or shall I
>> keep it local?
>
> For me scrub'ing takes several days without having a special big
> pool size and starting another scrub restarts everything.
> You should at least check if another one is still running.

Good point, I will have a look at this...

But I'm a little bit surprised, when I scrub a pool of 3 times 250 GB  
disks in RAIDZ configuration, it is finished fast (a fraction of a  
day... maybe an hour or two). Initially it displays a very long time  
(>400 hours), but this is reducing after a while drastically. The pool  
is filled up to 3/4 of the entire capacity.

> I think resilvering is also a collision case to check for.

No. Resilvering has higher priority than a scrub. From the man-page:
---snip---
                                                                If a
resilver is in progress, ZFS does not allow a scrub to  be  started
until the resilver completes.
---snip---

Bye,
Alexander.

-- 
Fairy Tale, n.:
	A horror story to prepare children for the newspapers.

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