Re: [PATCH] MD: Quickly return errors if too many devices have failed.

[Brassow Jonathan <jbrassow@redhat.com>]

On Mar 17, 2013, at 6:49 PM, NeilBrown wrote:

>> 
>> 
>> I would prefer to get immediate errors if nothing can be done to satisfy the
>> request and I've been thinking of something like the attached patch.  The
>> patch below is incomplete.  It does not take into account any reshaping that
>> is going on, nor does it try to figure out if a mirror set in RAID10 has died;
>> but I hope it gets the basic idea across.
>> 
>> Is this a good way to handle this situation, or am I missing something?
> 
> I think we do get immediate errors (once all bugs are fixed).
> Your patch does extra work for every request which is only of value if the
> array has failed - and it really doesn't make sense to optimise for a failed
> array.
> The current approach is to just try to satisfy a request and once we find
> that we need to do something that is impossible - return an error at that
> point.  I think that is best.
> 
> Can you try the commit I identified and see if it makes the problem go away?

Yes, that sounds better.  I will try with the commit you mentioned.

thanks,
 brassow