From mboxrd@z Thu Jan  1 00:00:00 1970
From: Mike Snitzer <snitzer@redhat.com>
Subject: Re: dm: pass up rotational flag
Date: Thu, 26 May 2011 14:43:21 -0400
Message-ID: <20110526184321.GC26219@redhat.com>
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To: "Martin K. Petersen" <martin.petersen@oracle.com>
Cc: Mandeep Singh Baines <msb@chromium.org>, linux-kernel@vger.kernel.org, jrbarnette@chromium.org, Neil Brown <neilb@suse.de>, Jens Axboe <jaxboe@fusionio.com>, Alasdair G Kergon <agk@redhat.com>, dm-devel@redhat.com
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On Thu, May 26 2011 at  2:29pm -0400,
Martin K. Petersen <martin.petersen@oracle.com> wrote:

> >>>>> "Mike" == Mike Snitzer <snitzer@redhat.com> writes:
> 
> >> Allow the NONROT flag to be passed through to linear mappings if all
> >> underlying device are non-rotational. Tools like ureadahead will
> >> schedule IOs differently based on the rotational flag.
> 
> Mike> Thanks for doing this, looks good in general.
> 
> I'd rather we made the rotational property part of the topology instead
> of having to special-case it in DM. I seem to recall posting a patch
> that did that at some point but I can't seem to find it...

Sure, that'd work too.

Similarly, couldn't the discard flag be made part of topology?

Mike