Sheesh, why is this guy's blog post getting so much attention all of
a sudden?  It's been out for months; suddenly, everyone's talking
about it.  I'll copy what I wrote in last week's thread on it:

On Fri, Oct 16, 2009 at 7:23 AM, Ben Scott <[email protected]> wrote:
>  As I understand it, the argument is: Given a 12 terabyte disk array,
> reading all of the blocks from all of the disks in the array will mean
> you've read enough data to reach the URE rate (Unrecoverable Read
> Error) quantity from the spec.  Since a RAID 5 rebuild means reading
> all of the blocks in the remaining good disks, you'll hit a URE and
> the controller pukes.  This is an issue now because while disks sizes
> have increased, the URE rate spec has remained constant.
> </restatement_of_argument>
>
>  One thought I have: Most RAID controllers, for the past few years,
> include a "Patrol Read" function that regularly reads all of the
> blocks from all of the disks in the array.  The author's argument
> would suggest that if you have a 12 TB array, it would immediately
> start failing the Patrol Reads from day one.  That doesn't seem to be
> happening.  Why not?  (While I don't have a 12 TB array, I know others
> do.)

-- Ben

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