Constant minor ZFS corruption

[Stephen McKay]

On Thursday, 10th March 2011, Doug Barton wrote:

>On 03/09/2011 04:41, Stephen McKay wrote:
>> Of the 12 disks, only 1 has been error-free.  I've been doing this for
>> about 10 days now and there is no pattern that I can see in the errors.
>
>Are all the disks from the same batch? If so, you likely got a bad batch.

They are all from the same batch, and this "bad batch" idea has gone
though my mind too, but we've taken 6 of the disks and built a raidz2
array in a different machine, and this time they seem to be error free.
These are the same disks that have already had corruption, according
to ZFS, when used in the original machine.

Apart from the obvious (that everything changed), the major change in
my eyes is that the other box (a Dell PowerEdge 840) runs the disks
at SATA1 speed, not SATA3.  There's no way to set these drives to run
at 1.5Gb/s via jumpers or I'd put them straight back in the main box
and test them.

Is there a way to tell FreeBSD to run disks at a slower transfer rate?
I've not seen any switches or tunables that apply with the mps driver.

Cheers,

Stephen.