Re: raidframe performance question

[Paul Goyette <paul%whooppee.com@localhost>]

Nope.  -A simply specifies the alignment of the DOS partitions (and the 
offset of the first partition).  If your drive might have "native" 
sectors larger than 512 bytes, you need to use this, otherwise all your 
I/Os will get split across drive-addressable sectors and performance 
will be very bad (tm) as the drive reads one physical sector, updates 
and re-writes the latter portion, then reads the next sector and updates 
the early portion.

Note that most versions of NetBSD's fdisk(8) have a parsing bug, and 
will not accept "-A 2048" (where the offset is supposed to default to 
the alignment).  Instead you have to specify "-A 2048/2048".  I fixed 
this error as soon as I found it!


On Fri, 13 May 2011, Dustin Marquess wrote:

> Is the -A 2048 option specific to "Advanced Format" disks?
>
> -Dustin
> On May 13, 2011 5:18 AM, "Paul Goyette" <paul%whooppee.com@localhost> wrote:
> > On Fri, 13 May 2011, Erik Fair wrote:
> >
> > > It is important to clearly point out that the fdisk stuff is i386
> > > specific.
> >
> > Good point - I've updated my master copy with (hopefully adequate)
> > verbage.
> >
> >
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| Paul Goyette     | PGP Key fingerprint:     | E-mail addresses:       |
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| Network Engineer | 0786 F758 55DE 53BA 7731 | pgoyette at juniper.net |
| Kernel Developer |                          | pgoyette at netbsd.org  |
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