On Monday March 5, eyal@xxxxxxxxxxxxxx wrote: > Neil Brown wrote: > [trim Q re how resync fixes data] > > For raid1 we 'fix' and inconsistency by arbitrarily choosing one copy > > and writing it over all other copies. > > For raid5 we assume the data is correct and update the parity. > > Can raid6 identify the bad block (two parity blocks could allow this > if only one block has bad data in a stripe)? If so, does it? No, it doesn't. I guess that maybe it could: Rebuild each block in turn based on the xor parity, and then test if the Q-syndrome is satisfied. but I doubt the gain would be worth the pain. What we really want in drives that store 520 byte sectors so that a checksum can be passed all the way up and down through the stack .... or something like that. NeilBrown - To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
