gpart and sector size

Dag-Erling Smørgrav des at
Thu Apr 8 14:24:14 UTC 2010

Alexey Tarasov <me at> writes:
> Ok, in case of GPT? :-)

I doubt it, but I don't know for sure.

> GPT implementation can be the simplest solution to this problem
> compared to implementing additional ATA commands to determine if disk
> is in Advanced Format.

There are two issues:

1) There is already an ATA command to report both physical and logical
   sector sizes, but the disk lies - it always reports 512/512.

2) The disk may have already been formatted on a system that doesn't
   support 4k sectors, and may contain unaligned partitions and file
   systems, which won't be visible if we forcibly and unconditionally
   use 4k sectors.

Dag-Erling Smørgrav - des at

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