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Date: Mon, 16 Apr 2018 17:04:12 -0400 (EDT)
From: Mikulas Patocka <mpatocka@redhat.com>
Subject: Re: slab: introduce the flag SLAB_MINIMIZE_WASTE
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To: Vlastimil Babka <vbabka@suse.cz>
Cc: Mike Snitzer <snitzer@redhat.com>, Christopher Lameter <cl@linux.com>, Matthew Wilcox <willy@infradead.org>, Pekka Enberg <penberg@kernel.org>, linux-mm@kvack.org, dm-devel@redhat.com, David Rientjes <rientjes@google.com>, Joonsoo Kim <iamjoonsoo.kim@lge.com>, Andrew Morton <akpm@linux-foundation.org>



On Mon, 16 Apr 2018, Vlastimil Babka wrote:

> On 04/13/2018 05:10 PM, Mike Snitzer wrote:
> > On Fri, Apr 13 2018 at  5:22am -0400,
> > Vlastimil Babka <vbabka@suse.cz> wrote:
> >>
> >> Would this perhaps be a good LSF/MM discussion topic? Mikulas, are you
> >> attending, or anyone else that can vouch for your usecase?
> > 
> > Any further discussion on SLAB_MINIMIZE_WASTE should continue on list.
> > 
> > Mikulas won't be at LSF/MM.  But I included Mikulas' dm-bufio changes
> > that no longer depend on this proposed SLAB_MINIMIZE_WASTE (as part of
> > the 4.17 merge window).
> 
> Can you or Mikulas briefly summarize how the dependency is avoided, and

This was Mike's misconception - dm-bufio actually needs the 
SLAB_MINIMIZE_WASTE patch, otherwise it is wasting memory.

> whether if (something like) SLAB_MINIMIZE_WASTE were implemented, the
> dm-bufio code would happily switch to it, or not?
> 
> Thanks,
> Vlastimil

Mikulas