Re: ATA 4 KiB sector issues.

From: H. Peter Anvin
Date: Sun Mar 14 2010 - 21:23:04 EST


On 03/10/2010 01:14 AM, Denys Vlasenko wrote:

63s/255h is more or less "standard" now.

Alignment issues can be solved by picking a good multiple of
_heads_ or _cylinders_:

For first partition, pick the start at 8th head:

cyl 0 head 1 sector 1: LBA sector 63) - bad
cyl 0 head 8 sector 1: LBA sector 8*63) - good (4k aligned)

For any other partition, pick start cylinder which is a multiple of 8:

cyl 8*x head 0 sector 1: LBA sector 8*x*255*63 - good (4k aligned)

This will actually work well for *any* geometry, not only for 63s/255h.

Yes, but it does squat for a flash disk that wants, say, 256K alignment.

-hpa
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