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Date: Fri, 19 Mar 2010 14:13:18 -0400
From: Phillip Susi <psusi@cfl.rr.com>
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Subject: [linux-lvm] Data alignment
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I have been trying to get my logical volume to be aligned to a 512 KB
boundary on my SSD so it lines up with the flash erase block.  I thought
I could do this with pvcreate --dataalign 1024, but this caused the data
to be aligned to a 1024 sector boundary within the partition, which
itself starts on sector 63.  I then thought the --dataalignoffsest
switch would help, but specifying 63 there caused the data to be moved
to sector 1087.  I tried giving it -63, but was told that a negative
number is not allowed.  Why not?  How can I get the data to start on
sector 1024-63 of the partition so it ends up on pysical sector 1024 of
the disk?