From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from cdptpa-omtalb.mail.rr.com ([75.180.132.120]:5217 "EHLO cdptpa-omtalb.mail.rr.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755263Ab2JKR6w (ORCPT ); Thu, 11 Oct 2012 13:58:52 -0400 Message-ID: <507708DA.3040804@ubuntu.com> Date: Thu, 11 Oct 2012 13:58:50 -0400 From: Phillip Susi MIME-Version: 1.0 To: Josef Bacik CC: Mitch Harder , linux-btrfs Subject: Re: Varying Leafsize and Nodesize in Btrfs References: <20120830162512.GA2879@localhost.localdomain> In-Reply-To: <20120830162512.GA2879@localhost.localdomain> Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-btrfs-owner@vger.kernel.org List-ID: -----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 On 8/30/2012 12:25 PM, Josef Bacik wrote: > Once you cross some hardware dependant threshold (usually past 32k) > you start incurring high memmove() overhead in most workloads. > Like all benchmarking its good to test your workload and see what > works best, but 16k should generally be the best option. Thanks, > > Josef Why are memmove()s neccesary, can they be avoided, and why do they incur more overhead with 32k+ sizes? -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.17 (MingW32) Comment: Using GnuPG with Mozilla - http://www.enigmail.net/ iQEcBAEBAgAGBQJQdwjZAAoJEJrBOlT6nu75rkYH/RYXBbAJfIG2KmmmFA8kSIiL EEvdA9KRnVH08h2lnB26xNdCPbf59M7GrH2hZK48gM9x4OQPzKXf8eCTYTy4mFKy mqTPFsgcPveTFtgoRXkuhZvUXMpFV4M8I7MLZRCcxk5KWTwA/slcunQxG7BMz/V4 tBxE8ya2Hxej2VJe4AbLR6PJbvCGsFXNlxBpUy9Qh7q0TmDeGzsoaZ1We1itNjQZ wWjTerka2qe9dyP8EOUp/uZqGUQXu1TUKbTLygsfMb11/vGMkoUkZtTa0f9lQosw 10UlA8TyqAkLX3gpQzsJVCwiRuNWQBbQqvdYq3dCQOgzBbvOdvD6TtmeS1saO4o= =qV0c -----END PGP SIGNATURE-----