Re: Questions about 4k sector drives

["Martin K. Petersen" <martin.petersen@oracle.com>]

>>>>> "Greg" == Greg Freemyer <greg.freemyer@gmail.com> writes:

Greg> In theory 4K physical sector drives with XP alignment will
Greg> eventually ship and possibly have already.

Well, that's a definite maybe :)

The 4K transition took much longer than anticipated and Vista and beyond
know how to query the drives for alignment.  So I'm guessing that we'll
only see 1-alignment via a jumper at this point.


Greg> I don't know it any those drives exist yet, or if they ever will.

I have a bunch, but obviously they are mostly prototypes.


Greg> mdadm should as well, not just blindly say 1MB is the magic
Greg> alignment point.  (ie. linux can do better than Win2008/Win2003
Greg> which simply disagree with each other on how to align.)

We're going with 1MB as default because that's the new storage industry
consensus.  It's a less formalized number than - say - IDEMA sector
counts, but it appears to have reached critical mass among the vendors.

And obviously we'll compensate if the storage device reports a different
alignment via the relevant ATA or SCSI knobs.

-- 
Martin K. Petersen	Oracle Linux Engineering