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Date: Mon, 14 May 2007 09:30:42 +0100
From: "Bryn M. Reeves" <breeves@redhat.com>
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Subject: Re: [linux-lvm] LVM on SATA/PATA disks
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David Brown wrote:
> Of course, any of the re-ordering (SCSI TCQ, or SATA NCQ) requires
> filesystem and driver support of write barriers for reliability.
> Write barriers are not implement in DM, hence LVM, so there is a

Only the dm-mpath and dm-snap targets treat barrier bios specially (they
return EOPNOTSUPP). Other dm targets pass the barriers on to the
underlying devices unchanged.

Regards,
Bryn.

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