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Re: Disks w/non-512-byte sectors?

On Jan 19, 2015, at 3:09 AM, Michael van Elst wrote:


I was of the impression that the 4K sector business was to address(!)
the problem of disk capacity outrunning the addressing capacity of the Task File interface on IDE/PATA/SATA disks, evening with all the funky
bit reassignments to squeeze out more address space and LBA tricks.

Current disks have LBA48, 48bit to address a sector. That's 128 Petabytes
(131072 Terabytes) with 512-byte sectors.

The above sounds like it's just a performance issue at the DAC level.

The larger sectors reduce per-sector command overhead and also squeeze
a few bits more onto the disk.

I was just reading that the ECC is improved, and possibly more efficient with the 4k sectors. Instead of 512 bytes of data, and so many bytes for ECC. Now the ECC is over the 4k, and
can correct more errors.

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