svn commit: r216230 - head/sys/cddl/contrib/opensolaris/uts/common/fs/zfs

[Erik Trulsson]

On Tue, Dec 07, 2010 at 01:57:04PM +0200, Andriy Gapon wrote:
> on 07/12/2010 13:51 Bruce Cran said the following:
> > On Tue, Dec 07, 2010 at 01:31:27PM +0200, Alexander Motin wrote:
> >> Not necessary. Some places indeed may have some legacy requirements,
> >> for example, in theory MBR want partition to be aligned to "track
> >> boundary" (but I've seen many pre-formatted SD cards with MBR
> >> violating it to align partition to flash sector). Same time for BSD
> >> label I see no problem to align partitions any way we want. I also
> >> see no problems to make FAT cluster, UFS block/fragment, etc, to
> >> match some sizes.
> > 
> >>From a new installation of Windows 7 and FreeBSD CURRENT:
> > 
> > GEOM: ada0: partition 3 does not start on a track boundary.
> > GEOM: ada0: partition 3 does not end on a track boundary.
> > GEOM: ada0: partition 2 does not start on a track boundary.
> > GEOM: ada0: partition 2 does not end on a track bounary.
> > 
> > Partition 2 is the reserved partition while 3 is an NTFS partition, both
> > created in the Windows setup application.
> > 
> > Since Windows isn't bothering to align partitions do we still need to
> > warn about it?
> > 
> 
> No.
> And another reason is that modern drives do not actually report any CHS
> parameters, so I don't even know where we get them and how we (pretend to) know
> we track boundaries are.

Modern drives do actually report CHS parameters.  The values reported
rarely (if ever) have any relationship whatsoever to reality, but they
are reported.  I guess the reason for them still being reported is to
satisfy old systems that do not undestand LBA and insist on getting CHS
parameters.



-- 
<Insert your favourite quote here.>
Erik Trulsson
ertr1013 at student.uu.se