Re: RAID-10 keeps aborting

["H. Peter Anvin" <hpa@zytor.com>]

On 06/04/2013 11:32 AM, Dan Williams wrote:
> On Tue, Jun 4, 2013 at 11:04 AM, Martin K. Petersen
> <martin.petersen@oracle.com> wrote:
>>>>>>> "hpa" == H Peter Anvin <hpa@zytor.com> writes:
>>
>> hpa> One subdevice accepts it and the other doesn't, presumably.
>>
>> Ah. Well fail the command and let the block layer deal with it. This is
>> really no different from the discard case.
> 
> Which md also does not handle if the device later returns "illegal
> request" to a discard command.  My point about one device accepting
> the write and another device dropping it is we now have an
> inconsistent array and a write command to complete.  So I don't see
> how md can wait/trust that the upper layer will retry and fix things
> up?    Translate and retry internally for these command types, return
> success to the original request, and disable future requests.
> 

Well, if that is what the block device layer is defined to do then that
is what the block layer does.  It makes sense from the point of view of
a disk, there block layer has to translate and redo, so if the block
layer is defined to do that, why not rely on it?

	-hpa