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Sheffield, Robert L wrote:
I think when RAID vendors begin to use the WRITE WRONG commands in practice, we'll find the capability it offers will be weak with respect to what's needed for robust RAID algorithms.
I would agree. I don't see how Write Wrong has much value for any kind of RAID implementation. And I'm not sure how it would work when the physical sector contains more than one logical sector or how it works with the more complex ECC algorithms that will be used in the future.
And related to this: I don't see how attempting to read and use the data in a sector that has an uncorrectable ECC error is much value either. Given today and future ECC algorithms it is likely that none of the data in a sector is of any value if there is an uncorrectable ECC error anywhere in the sector's data.
Metadata? Cool... Define a way the host can store metadata associated with each sector on the disk - expand the basic sector size by 32 or 64 bytes for the metadata and define new commands to access the metadata. (This would probebly be of more value to more people than that stupid NV cache thing.)
Hale -- ++ Hale Landis ++ www.ata-atapi.com ++
