From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:53845) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cQQhi-0007W0-RM for qemu-devel@nongnu.org; Sun, 08 Jan 2017 22:33:03 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1cQQhd-0007RJ-Tq for qemu-devel@nongnu.org; Sun, 08 Jan 2017 22:33:02 -0500 Received: from mx1.redhat.com ([209.132.183.28]:39616) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1cQQhd-0007R8-Nv for qemu-devel@nongnu.org; Sun, 08 Jan 2017 22:32:57 -0500 References: <1483690133-25104-1-git-send-email-lprosek@redhat.com> From: Jason Wang Message-ID: Date: Mon, 9 Jan 2017 11:32:48 +0800 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: quoted-printable Subject: Re: [Qemu-devel] [PATCH] net: optimize checksum computation List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Dmitry Fleytman , Ladi Prosek Cc: qemu-devel@nongnu.org On 2017=E5=B9=B401=E6=9C=8808=E6=97=A5 17:03, Dmitry Fleytman wrote: >> On 6 Jan 2017, at 10:08 AM, Ladi Prosek wrote: >> >> Very simple loop optimization with a significant performance impact. >> >> Microbenchmark results, modern x86-64: >> >> buffer size | speed up >> ------------+--------- >> 1500 | 1.7x >> 64 | 1.5x >> 8 | 1.15x >> >> Microbenchmark results, POWER7: >> >> buffer size | speed up >> ------------+--------- >> 1500 | 5x >> 64 | 3.3x >> 8 | 1.13x >> >> There is a lot of room for further improvement at the expense of >> code complexity - aligned multibyte reads, LE/BE considerations, >> architecture-specific optimizations, etc. This patch still keeps >> things simple and readable. > Reviewed-by: Dmitry Fleytman > Applied to -net. Thanks