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Date: Thu, 22 Apr 2010 08:13:42 +0200
From: Luca Berra <bluca@comedia.it>
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Subject: Re: [linux-lvm] resize an LVM physical volume
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On Wed, Apr 21, 2010 at 02:58:32PM +0000, behzad wrote:
>I did the test by changing the sector at the start and the same things happened
please dump the existing partition data using sfdisk -d, then we can
talk about facts.

>,the partion was no more in pvdisplay list (I'll be on client site can verify
>that hope it must be the reason) , but What might happens that the fdisk changes
>the start sector of a partition when we re-create a partition ?
because fdisk by default creates an ms-dos compatible partition table
that starts on sector 63.

Since most storage array do read/write whole cache block to the disk and
no cache has a block size of 31.5K. Most storage vendors will tell you
to align the partition start to cache boundary (usually 64K or 128K)

Even M$ finally realized that and they create partitions starting at 1MB
from w2008 onwards.

L.

-- 
Luca Berra -- bluca@comedia.it
         Communication Media & Services S.r.l.
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