[Beowulf] Big storage

[Mark Hahn]

>> During a READ operation, if the RAID controller finds an unreadable
>> (uncorrectable) disk sector, then it will immediately reconstruct the
>> missing data for that sector using redundant data from the rest of the
>> array, and WRITE that data to the unreadable (uncorrectable) sector to
>> force sector reallocation if needed by the disk.

I don't believe MD does online scrubbing.  but you _can_ trigger it
to do a check and/or scrub cycle (of the whole array, I think).

>> features.  The absence of these features is the main reason that I don't
>> think Linux software RAID is very good.

as always, the main advantage to open-source, software implementations 
is malleability.  MD improves fast.

> quite a while ago and use it heavily. Presumably the maintainers (Neil
> Brown? or is he just the mdadm maintainer) are aware of this lack/criticism?

Niel is very responsive and responsible.

> As presented, it certainly seems like features that ought to be added.
> It would be interesting to cc LKML for comment.

linux-raid at vger.kernel.org is the real nexus of md stuff.  feel free to 
redirect followups there...

regards, mark hahn.