From: Matthew Wilcox <willy@infradead.org>
To: Vlastimil Babka <vbabka@suse.cz>
Cc: lsf-pc@lists.linux-foundation.org,
Linux-FSDevel <linux-fsdevel@vger.kernel.org>,
linux-mm <linux-mm@kvack.org>,
linux-block@vger.kernel.org, Michal Hocko <mhocko@kernel.org>,
Christoph Lameter <cl@linux.com>,
David Rientjes <rientjes@google.com>,
Pekka Enberg <penberg@kernel.org>,
Joonsoo Kim <iamjoonsoo.kim@lge.com>,
Ming Lei <ming.lei@redhat.com>,
linux-xfs@vger.kernel.org, Christoph Hellwig <hch@infradead.org>,
Dave Chinner <david@fromorbit.com>,
"Darrick J . Wong" <darrick.wong@oracle.com>
Subject: Re: [LSF/MM TOPIC] guarantee natural alignment for kmalloc()?
Date: Thu, 25 Apr 2019 04:33:59 -0700 [thread overview]
Message-ID: <20190425113358.GI19031@bombadil.infradead.org> (raw)
In-Reply-To: <20190411132819.GB22763@bombadil.infradead.org>
On Thu, Apr 11, 2019 at 06:28:19AM -0700, Matthew Wilcox wrote:
> On Thu, Apr 11, 2019 at 02:52:08PM +0200, Vlastimil Babka wrote:
> > In the session I hope to resolve the question whether this is indeed the
> > right thing to do for all kmalloc() users, without an explicit alignment
> > requests, and if it's worth the potentially worse
> > performance/fragmentation it would impose on a hypothetical new slab
> > implementation for which it wouldn't be optimal to split power-of-two
> > sized pages into power-of-two-sized objects (or whether there are any
> > other downsides).
>
> I think this is exactly the kind of discussion that LSFMM is for! It's
> really a whole-system question; is Linux better-off having the flexibility
> for allocators to return non-power-of-two aligned memory, or allowing
> consumers of the kmalloc API to assume that "sufficiently large" memory
> is naturally aligned.
This has been scheduled for only the MM track. I think at least the
filesystem people should be involved in this discussion since it's for
their benefit.
Do we have an lsf-discuss mailing list this year? Might be good to
coordinate arrivals / departures for taxi sharing purposes.
next prev parent reply other threads:[~2019-04-25 11:34 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-04-11 12:52 [LSF/MM TOPIC] guarantee natural alignment for kmalloc()? Vlastimil Babka
2019-04-11 13:28 ` Matthew Wilcox
2019-04-25 11:33 ` Matthew Wilcox [this message]
2019-04-25 12:03 ` Martin K. Petersen
2019-04-25 12:03 ` Michal Hocko
2019-04-12 7:14 ` James Bottomley
2019-04-12 7:54 ` Vlastimil Babka
2019-04-16 15:38 ` Christopher Lameter
2019-04-17 8:07 ` Vlastimil Babka
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