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From: Stuart D Gathman <stuart@bmsi.com>
To: linux-lvm@redhat.com
Subject: Re: [linux-lvm] Non 512 byte sectors
Date: Fri, 14 Dec 2012 13:52:39 -0500	[thread overview]
Message-ID: <50CB7577.4050906@bmsi.com> (raw)
In-Reply-To: <50C9F2D6.7090802@ubuntu.com>

On 12/13/2012 10:23 AM, Phillip Susi expounded in part:
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> Is it possible to get dm to report > 512 byte sector size?  If so, how?
>
>
blockdev --getss /dev/vg/lv  (or any other block device)

That is probably logical sector size, however.  The only way I know to 
get physical sector size is:

hdparm -I /dev/sda

which reports logical and physical sector size.  Some WD devices are 
known to lie about physical sector size, however.

If you always align stuff to 4096, there won't be a problem.  In fact, 
new technology tends to have much larger alignment requirements for 
optimum performance - say 128k, the size of an erase block, or 64k for a 
RAID chunk size.  So aligning everything to 1M should hold you for a while.

  reply	other threads:[~2012-12-14 18:52 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-12-13 15:23 [linux-lvm] Non 512 byte sectors Phillip Susi
2012-12-14 18:52 ` Stuart D Gathman [this message]
2012-12-14 19:29 ` Mike Snitzer
2012-12-14 19:56   ` Phillip Susi
2012-12-14 20:10     ` Mike Snitzer
2012-12-14 22:05       ` Phillip Susi

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