Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754519AbbKMLwG (ORCPT ); Fri, 13 Nov 2015 06:52:06 -0500 Received: from mezzanine.sirena.org.uk ([106.187.55.193]:58358 "EHLO mezzanine.sirena.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751939AbbKMLwE (ORCPT ); Fri, 13 Nov 2015 06:52:04 -0500 Date: Fri, 13 Nov 2015 11:51:44 +0000 From: Mark Brown To: Jens Axboe Cc: Baolin Wang , Mike Snitzer , Alasdair G Kergon , dm-devel@redhat.com, neilb@suse.com, linux-raid@vger.kernel.org, jack@suse.cz, Arnd Bergmann , LKML , keith.busch@intel.com, jmoyer@redhat.com, tj@kernel.org, bart.vanassche@sandisk.com, "Garg, Dinesh" Message-ID: <20151113115144.GR12392@sirena.org.uk> References: <20151111181813.GD12236@redhat.com> <20151112100422.GM12392@sirena.org.uk> <5644AFA2.6040201@kernel.dk> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="562f9N4fbIs+fPrJ" Content-Disposition: inline In-Reply-To: <5644AFA2.6040201@kernel.dk> X-Cookie: We have DIFFERENT amounts of HAIR -- User-Agent: Mutt/1.5.24 (2015-08-30) X-SA-Exim-Connect-IP: 94.175.94.161 X-SA-Exim-Mail-From: broonie@sirena.org.uk Subject: Re: [PATCH 0/2] Introduce the request handling for dm-crypt X-SA-Exim-Version: 4.2.1 (built Mon, 26 Dec 2011 16:24:06 +0000) X-SA-Exim-Scanned: Yes (on mezzanine.sirena.org.uk) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2069 Lines: 52 --562f9N4fbIs+fPrJ Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Thu, Nov 12, 2015 at 08:26:26AM -0700, Jens Axboe wrote: > On 11/12/2015 03:04 AM, Mark Brown wrote: > >Android now wants to encrypt phones and tablets by default and have been > >seeing substantial performance hits as a result, we can try to get > >people to share performance data from productionish systems but it might > >be difficult. > Well, shame on them for developing out-of-tree, looks like they are reapi= ng > all the benefits of that. > Guys, we need some numbers, enough with the hand waving. There's no point > discussing this further until we know how much of a difference it makes to > handle X MB chunks instead of Y MB chunks. As was previously stated, unle= ss > there's a _substantial_ performance benefit, this patchset isn't going > anywhere. Yeah, what I'm saying here is that there will issues getting the numbers =66rom relevant production systems - we are most likely to be looking at proxies which are hopefully reasonably representative but there's likely to be more divergence than you'd see just running benchmark workloads on similar systems to those used in production. --562f9N4fbIs+fPrJ Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v2 iQEcBAEBCAAGBQJWRc7PAAoJECTWi3JdVIfQVssH/3H4CZgV1sXNGbagnlJMH4PF wfNmBCGuN6mRIeqEoBFJEmj7ol+bw099rQyVGNh1gTLIJScGRgaqM68cQwvhoNAY vQdUXl5GBtx2gzn6esBcNaH0FCj39PXFl4476JmsoMeegdqM+w+Lf2ftZzC1asKQ 0Ee5tv7Brn/VNCLYhmLPtwLkLfiA15/yWtV3JADa1cak+gYoszPMYqt3DYCjyqn6 RdUYZN1NaOnoVVKD8ef/MAK6SS6S40I4/ud8VGWXNc0OKAZ9CD5rzVnNwEY7cwfY cQ07/wCwC4GIKKoAJIDIaR6kIzenE0XlR8kycpW32hWdy3US/mdtsmChzCG359A= =WM5U -----END PGP SIGNATURE----- --562f9N4fbIs+fPrJ-- -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/