From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: <t.lamprecht@proxmox.com> Received: from firstgate.proxmox.com (firstgate.proxmox.com [212.224.123.68]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by lists.proxmox.com (Postfix) with ESMTPS id 86D6C9E414 for <pve-devel@lists.proxmox.com>; Tue, 31 Oct 2023 10:52:46 +0100 (CET) Received: from firstgate.proxmox.com (localhost [127.0.0.1]) by firstgate.proxmox.com (Proxmox) with ESMTP id 60501192FA for <pve-devel@lists.proxmox.com>; Tue, 31 Oct 2023 10:52:16 +0100 (CET) Received: from proxmox-new.maurer-it.com (proxmox-new.maurer-it.com [94.136.29.106]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by firstgate.proxmox.com (Proxmox) with ESMTPS for <pve-devel@lists.proxmox.com>; Tue, 31 Oct 2023 10:52:15 +0100 (CET) Received: from proxmox-new.maurer-it.com (localhost.localdomain [127.0.0.1]) by proxmox-new.maurer-it.com (Proxmox) with ESMTP id 85A7D42D2D for <pve-devel@lists.proxmox.com>; Tue, 31 Oct 2023 10:52:15 +0100 (CET) Message-ID: <ae28569f-9810-41d7-94f9-9131a29b9d41@proxmox.com> Date: Tue, 31 Oct 2023 10:52:12 +0100 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Content-Language: en-GB To: Proxmox VE development discussion <pve-devel@lists.proxmox.com>, Stefan Hanreich <s.hanreich@proxmox.com> References: <20230918154656.2717366-1-s.hanreich@proxmox.com> From: Thomas Lamprecht <t.lamprecht@proxmox.com> In-Reply-To: <20230918154656.2717366-1-s.hanreich@proxmox.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-SPAM-LEVEL: Spam detection results: 0 AWL -0.069 Adjusted score from AWL reputation of From: address BAYES_00 -1.9 Bayes spam probability is 0 to 1% DMARC_MISSING 0.1 Missing DMARC policy KAM_DMARC_STATUS 0.01 Test Rule for DKIM or SPF Failure with Strict Alignment SPF_HELO_NONE 0.001 SPF: HELO does not publish an SPF Record SPF_PASS -0.001 SPF: sender matches SPF record T_SCC_BODY_TEXT_LINE -0.01 - URIBL_BLOCKED 0.001 ADMINISTRATOR NOTICE: The query to URIBL was blocked. 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[proxmox.com] Subject: [pve-devel] applied: [PATCH pve-ceph] fix compatibility with CPUs not supporting SSE 4.1 instructions X-BeenThere: pve-devel@lists.proxmox.com X-Mailman-Version: 2.1.29 Precedence: list List-Id: Proxmox VE development discussion <pve-devel.lists.proxmox.com> List-Unsubscribe: <https://lists.proxmox.com/cgi-bin/mailman/options/pve-devel>, <mailto:pve-devel-request@lists.proxmox.com?subject=unsubscribe> List-Archive: <http://lists.proxmox.com/pipermail/pve-devel/> List-Post: <mailto:pve-devel@lists.proxmox.com> List-Help: <mailto:pve-devel-request@lists.proxmox.com?subject=help> List-Subscribe: <https://lists.proxmox.com/cgi-bin/mailman/listinfo/pve-devel>, <mailto:pve-devel-request@lists.proxmox.com?subject=subscribe> X-List-Received-Date: Tue, 31 Oct 2023 09:52:46 -0000 On 18/09/2023 17:46, Stefan Hanreich wrote: > One of our users ran into issues with running Ceph on older CPU > architectures [1]. This is apparently due to a bug in gcc-12 that > leads to SSE 4.1 instructions always being executed rather than > dynamically dispatching functions using those instructions. Those > binaries then break on older CPUs that do not support this instruction > set. > > I've ran some benchmarks with `rados bench` against our last release > (18.2.0-pve2) and this new version. The commands were taken from our > latest Ceph benchmarking paper [2]. The results showed that this patch > does not lead to performance regressions on newer hardware. > > 18.2.0-pve2 this patch > Read EC 4574.28 4651.95 > Write EC 3739.59 3773.87 > Read Replicated 5345.34 5568.41 > Write Replicated 4123.28 4066.19 > (numbers correspond to bandwidth in MB/s) > > [1] https://forum.proxmox.com/threads/proxmox-8-ceph-quincy-monitor-no-longer-working-on-amd-opteron-2427.129613 > [2] https://www.proxmox.com/en/downloads/proxmox-virtual-environment/documentation/proxmox-ve-ceph-benchmark-2020-09 > > Signed-off-by: Stefan Hanreich <s.hanreich@proxmox.com> > --- > ...y-with-CPUs-not-supporting-SSE-4.1-i.patch | 32 +++++++++++++++++++ > patches/series | 1 + > 2 files changed, 33 insertions(+) > create mode 100644 patches/0015-fix-compatibility-with-CPUs-not-supporting-SSE-4.1-i.patch > > applied, with a reworded commit message, shifting the blame to the combination of gf-complete and gcc-12, as the former does some rather funky stuff too, thanks! Having this reported to the GCC and/or gf-complete people, ideally with a reduced example (compiling ceph is a bit overkill ;-) Using elfx86exts [0] as mentioned in the debian bug [1] should be enough to ensure your reduced example is still affected and contains SSE 4.1 instructions. [0]: https://github.com/pkgw/elfx86exts [1]: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1012935#10