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

quoted

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