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Date:   Tue, 17 Apr 2018 08:44:14 +0200
From:   Michal Hocko <mhocko@kernel.org>
To:     Vlastimil Babka <vbabka@suse.cz>
Cc:     Johannes Weiner <hannes@cmpxchg.org>,
        Minchan Kim <minchan@kernel.org>, Roman Gushchin <guro@fb.com>,
        linux-mm@kvack.org, Andrew Morton <akpm@linux-foundation.org>,
        Alexander Viro <viro@zeniv.linux.org.uk>,
        linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org,
        kernel-team@fb.com, lsf-pc@lists.linux-foundation.org
Subject: Re: [PATCH 3/3] dcache: account external names as indirectly
 reclaimable memory
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[the head of the thread is http://lkml.kernel.org/r/08524819-14ef-81d0-fa90-d7af13c6b9d5@suse.cz]

On Mon 16-04-18 21:57:50, Vlastimil Babka wrote:
> On 04/16/2018 02:27 PM, Michal Hocko wrote:
> > On Mon 16-04-18 14:06:21, Vlastimil Babka wrote:
> >>
> >> For example the percpu (and other) array caches...
> >>
> >>> maybe it will turn out that such a large
> >>> portion of the chache would need to duplicate the state that a
> >>> completely new cache would be more reasonable.
> >>
> >> I'm afraid that's the case, yes.
> >>
> >>> Is this worth exploring
> >>> at least? I mean something like this should help with the fragmentation
> >>> already AFAIU. Accounting would be just free on top.
> >>
> >> Yep. It could be also CONFIG_urable so smaller systems don't need to
> >> deal with the memory overhead of this.
> >>
> >> So do we put it on LSF/MM agenda?
> > 
> > If you volunteer to lead the discussion, then I do not have any
> > objections.
> 
> Sure, let's add the topic of SLAB_MINIMIZE_WASTE [1] as well.
> 
> Something like "Supporting reclaimable kmalloc caches and large
> non-buddy-sized objects in slab allocators" ?
> 
> [1] https://marc.info/?l=linux-mm&m=152156671614796&w=2

OK, noted.

-- 
Michal Hocko
SUSE Labs