From owner-freebsd-stable@freebsd.org Fri Dec 6 05:25:46 2019 Return-Path: Delivered-To: freebsd-stable@mailman.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.nyi.freebsd.org (Postfix) with ESMTP id EDB9A1B999D for ; Fri, 6 Dec 2019 05:25:46 +0000 (UTC) (envelope-from darius@dons.net.au) Received: from ipmail01.adl6.internode.on.net (ipmail01.adl6.internode.on.net [150.101.137.136]) by mx1.freebsd.org (Postfix) with ESMTP id 47TgzD30Ttz42c2 for ; Fri, 6 Dec 2019 05:25:43 +0000 (UTC) (envelope-from darius@dons.net.au) Received: from ppp14-2-112-104.adl-apt-pir-bras32.tpg.internode.on.net (HELO midget.dons.net.au) ([14.2.112.104]) by ipmail01.adl6.internode.on.net with ESMTP; 06 Dec 2019 15:54:10 +1030 Received: from midget.dons.net.au (localhost [127.0.0.1]) by midget.dons.net.au (8.15.2/8.15.2) with ESMTPS id xB65NtgP027003 (version=TLSv1.3 cipher=TLS_AES_256_GCM_SHA384 bits=256 verify=NO) for ; Fri, 6 Dec 2019 15:54:05 +1030 (ACDT) (envelope-from darius@dons.net.au) Received: (from mailnull@localhost) by midget.dons.net.au (8.15.2/8.15.2/Submit) id xB65LA5N026838 for ; Fri, 6 Dec 2019 15:51:10 +1030 (ACDT) (envelope-from darius@dons.net.au) X-Authentication-Warning: midget.dons.net.au: mailnull set sender to using -f X-MIMEDefang-Relay-be813b1f1da6d6b27d681222cb70cc4f5b642383: 203.31.81.177 Received: from [203.31.81.177] ([203.31.81.177]) by ppp14-2-112-104.adl-apt-pir-bras32.tpg.internode.on.net (envelope-sender ) (MIMEDefang) with ESMTP id xB65L5TK026837; Fri, 06 Dec 2019 15:51:10 +1030 From: "O'Connor, Daniel" Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: quoted-printable Mime-Version: 1.0 (Mac OS X Mail 12.4 \(3445.104.11\)) Date: Fri, 6 Dec 2019 15:51:04 +1030 Subject: Disabling speculative execution mitigations Message-Id: To: freebsd-stable X-Mailer: Apple Mail (2.3445.104.11) X-Spam-Score: 1.4 (*) No, score=1.4 required=5.0 tests=HELO_MISC_IP, RDNS_NONE, SPF_NONE autolearn=no autolearn_force=no version=3.4.2 X-Scanned-By: MIMEDefang 2.83 on 10.0.2.1 X-Rspamd-Queue-Id: 47TgzD30Ttz42c2 X-Spamd-Bar: ++++ Authentication-Results: mx1.freebsd.org; dkim=none; dmarc=none; spf=none (mx1.freebsd.org: domain of darius@dons.net.au has no SPF policy when checking 150.101.137.136) smtp.mailfrom=darius@dons.net.au X-Spamd-Result: default: False [4.91 / 15.00]; MV_CASE(0.50)[]; HAS_XAW(0.00)[]; RCVD_COUNT_THREE(0.00)[4]; TO_DN_ALL(0.00)[]; RCVD_NO_TLS_LAST(0.10)[]; RCVD_IN_DNSWL_LOW(-0.10)[136.137.101.150.list.dnswl.org : 127.0.5.1]; R_DKIM_NA(0.00)[]; MIME_TRACE(0.00)[0:+]; ASN(0.00)[asn:4739, ipnet:150.101.0.0/16, country:AU]; MID_RHS_MATCH_FROM(0.00)[]; FROM_EQ_ENVFROM(0.00)[]; ARC_NA(0.00)[]; FROM_HAS_DN(0.00)[]; TO_MATCH_ENVRCPT_ALL(0.00)[]; MIME_GOOD(-0.10)[text/plain]; PREVIOUSLY_DELIVERED(0.00)[freebsd-stable@freebsd.org]; DMARC_NA(0.00)[dons.net.au]; AUTH_NA(1.00)[]; RCPT_COUNT_ONE(0.00)[1]; NEURAL_SPAM_MEDIUM(0.98)[0.979,0]; IP_SCORE(1.53)[ip: (3.72), ipnet: 150.101.0.0/16(2.57), asn: 4739(1.36), country: AU(0.01)]; NEURAL_SPAM_LONG(1.00)[0.998,0]; R_SPF_NA(0.00)[] X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 06 Dec 2019 05:25:47 -0000 Hi, I am trying to track down a performance drop with the ASPEED xorg video = driver between FreeBSD 11 and 12 (I'm not expecting miracles from it but = it was basically unusable..) I wondered if some of the speculative execution mitigations could be = causing the problem so I did some digging and found these.. vm.pmap.pti=3D"0" # Disable page table isolation hw.ibrs_disable=3D"1" # Disable Indirect Branch Restricted = Speculation hw.mds_disable=3D"0" # Disable Microarchitectural Data Sampling = flush hw.vmm.vmx=3D"1" # Don't flush RSB on vmexit (presumably only = affects bhyve etc) hw.lazy_fpu_switch=3D"1" # Lazily flush FPU Does anyone know of any others? I have 2 systems with the same motherboard (Supermicro X11SSH-F), one is = older and runs FreeBSD 11 (and had an older BIOS_ and the newer runs = FreeBSD 12. FWIW on FreeBSD 11 the performance (measured by a subset of x11perf = benchmarks) went down 40% after updating to the latest BIOS (2.2a). = Unfortunately on FreeBSD 12 rolling back to the original BIOS (2.2) did = not improve performance. -- Daniel O'Connor "The nice thing about standards is that there are so many of them to choose from." -- Andrew Tanenbaum