From owner-svn-src-all@freebsd.org Wed Jun 29 23:56:25 2016 Return-Path: Delivered-To: svn-src-all@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id B705EB8715D; Wed, 29 Jun 2016 23:56:25 +0000 (UTC) (envelope-from cperciva@FreeBSD.org) Received: from repo.freebsd.org (repo.freebsd.org [IPv6:2610:1c1:1:6068::e6a:0]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 79BCA2B92; Wed, 29 Jun 2016 23:56:25 +0000 (UTC) (envelope-from cperciva@FreeBSD.org) Received: from repo.freebsd.org ([127.0.1.37]) by repo.freebsd.org (8.15.2/8.15.2) with ESMTP id u5TNuOl3057122; Wed, 29 Jun 2016 23:56:24 GMT (envelope-from cperciva@FreeBSD.org) Received: (from cperciva@localhost) by repo.freebsd.org (8.15.2/8.15.2/Submit) id u5TNuODh057121; Wed, 29 Jun 2016 23:56:24 GMT (envelope-from cperciva@FreeBSD.org) Message-Id: <201606292356.u5TNuODh057121@repo.freebsd.org> X-Authentication-Warning: repo.freebsd.org: cperciva set sender to cperciva@FreeBSD.org using -f From: Colin Percival Date: Wed, 29 Jun 2016 23:56:24 +0000 (UTC) To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r302288 - head/release/tools X-SVN-Group: head MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-BeenThere: svn-src-all@freebsd.org X-Mailman-Version: 2.1.22 Precedence: list List-Id: "SVN commit messages for the entire src tree \(except for " user" and " projects" \)" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 29 Jun 2016 23:56:25 -0000 Author: cperciva Date: Wed Jun 29 23:56:24 2016 New Revision: 302288 URL: https://svnweb.freebsd.org/changeset/base/302288 Log: Enable indirect segment I/Os by default in the Xen blkfront driver when running on EC2. Due to improvements in EC2, the performance penalty which was present on some EC2 instances no longer exists, and enabling this feature now consistently yields ~20% higher throughput with equal or lower latency. Reverts: r286063 Approved by: re (gjb) MFC after: 2 weeks Relnotes: Improved disk throughput on EC2 Modified: head/release/tools/ec2.conf Modified: head/release/tools/ec2.conf ============================================================================== --- head/release/tools/ec2.conf Wed Jun 29 23:33:44 2016 (r302287) +++ head/release/tools/ec2.conf Wed Jun 29 23:56:24 2016 (r302288) @@ -72,11 +72,6 @@ vm_extra_pre_umount() { # nodes, but apply the workaround just in case. echo 'hw.broken_txfifo="1"' >> ${DESTDIR}/boot/loader.conf - # Some EC2 instances suffer a significant (~40%) reduction in - # throughput when using blkif indirect segment I/Os. Disable this - # by default for now. - echo 'hw.xbd.xbd_enable_indirect="0"' >> ${DESTDIR}/boot/loader.conf - # Some EC2 instances run on a version of Xen which has a bug relating # to the migration of MSI-X interrupts; this is visible as SR-IOV # networking (aka. "EC2 Enhanced Networking") not being able to pass