From mboxrd@z Thu Jan  1 00:00:00 1970
From: Mike Snitzer <snitzer@redhat.com>
Subject: Re: dm: Make MIN_IOS, et al, tunable via sysctl.
Date: Mon, 19 Aug 2013 09:40:39 -0400
Message-ID: <20130819134038.GA27167@redhat.com>
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 <20130817123039.GR1762@agk-dp.fab.redhat.com>
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To: Frank Mayhar <fmayhar@google.com>, linux-kernel@vger.kernel.org, dm-devel@redhat.com
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On Sat, Aug 17 2013 at  8:30am -0400,
Alasdair G Kergon <agk@redhat.com> wrote:

> On Fri, Aug 16, 2013 at 03:55:21PM -0700, Frank Mayhar wrote:
> > This patch fixes that by changing the hardcoded MIN_IOS (and certain
> > other) #defines in dm-crypt, dm-io, dm-mpath, dm-snap and dm itself to
> > sysctl-modifiable values.  This lets us change the size of these pools
> > on the fly, we can reduce the size of the pools and reduce memory
> > pressure.
>  
> Did you consider using module_param_named()?
> (E.g. dm_verity_prefetch_cluster in dm-verity.)

Right, I'd prefer to see this be implemented in terms of
module_param_named().  Aside from dm-verity, dm-bufio.c makes the most
use of it.

Mike