From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mp2 ([2001:41d0:2:4a6f::]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) by ms11 with LMTPS id COYPKhhTU2A6GgAA0tVLHw (envelope-from ) for ; Thu, 18 Mar 2021 13:18:16 +0000 Received: from aspmx1.migadu.com ([2001:41d0:2:4a6f::]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) by mp2 with LMTPS id EPvJJRhTU2A3eAAAB5/wlQ (envelope-from ) for ; Thu, 18 Mar 2021 13:18:16 +0000 Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by aspmx1.migadu.com (Postfix) with ESMTPS id 06593252AC for ; Thu, 18 Mar 2021 14:18:16 +0100 (CET) Received: from localhost ([::1]:50182 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1lMsXW-00043t-Tn for larch@yhetil.org; Thu, 18 Mar 2021 09:18:14 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:40364) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lMsXL-00041X-1v for bug-guix@gnu.org; Thu, 18 Mar 2021 09:18:03 -0400 Received: from debbugs.gnu.org ([209.51.188.43]:33789) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1lMsXK-0004Wj-Pq for bug-guix@gnu.org; Thu, 18 Mar 2021 09:18:02 -0400 Received: from Debian-debbugs by debbugs.gnu.org with local (Exim 4.84_2) (envelope-from ) id 1lMsXK-0007cm-Hx for bug-guix@gnu.org; Thu, 18 Mar 2021 09:18:02 -0400 X-Loop: help-debbugs@gnu.org Subject: bug#47218: glibc 2.33's HWCAPS and GCC Function Multiversioning for performance Resent-From: Ludovic =?UTF-8?Q?Court=C3=A8s?= Original-Sender: "Debbugs-submit" Resent-CC: bug-guix@gnu.org Resent-Date: Thu, 18 Mar 2021 13:18:02 +0000 Resent-Message-ID: Resent-Sender: help-debbugs@gnu.org X-GNU-PR-Message: followup 47218 X-GNU-PR-Package: guix X-GNU-PR-Keywords: To: =?UTF-8?Q?L=C3=A9o?= Le Bouter Received: via spool by 47218-submit@debbugs.gnu.org id=B47218.161607347229291 (code B ref 47218); Thu, 18 Mar 2021 13:18:02 +0000 Received: (at 47218) by debbugs.gnu.org; 18 Mar 2021 13:17:52 +0000 Received: from localhost ([127.0.0.1]:45335 helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1lMsXA-0007cN-0q for submit@debbugs.gnu.org; Thu, 18 Mar 2021 09:17:52 -0400 Received: from mail3-relais-sop.national.inria.fr ([192.134.164.104]:22253) by debbugs.gnu.org with esmtp (Exim 4.84_2) (envelope-from ) id 1lMsX8-0007c9-4Q for 47218@debbugs.gnu.org; Thu, 18 Mar 2021 09:17:50 -0400 IronPort-HdrOrdr: A9a23:ryT3vKOVhEfDB8BcTlGjsMiAIKoaSvp033AA3SlKJCB9WMqeisyogbAnzhfykjkcQzUNntqHNamGTxrnhPpIyKMWOqqvWxSjhXuwIOhZnO7f6hDpBiGWzIBg/Ih6dawWMrbNJHh8yf33+QypV+snqePnzImNpcPzi0hgVhtrbaYI1XYaNi++HldtTAdLQboVfaD92uN9qzCteWsaY62AbxE4dtPOqNHRmJXtbQRuPXEawTOThjCl4qOSKXSl9yoZOgkk/Z4f62Tf1yT26qK/2svLqSPh6w== X-IronPort-AV: E=Sophos;i="5.81,258,1610406000"; d="scan'208";a="376134145" Received: from 91-160-117-201.subs.proxad.net (HELO ribbon) ([91.160.117.201]) by mail3-relais-sop.national.inria.fr with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 18 Mar 2021 14:17:43 +0100 From: Ludovic =?UTF-8?Q?Court=C3=A8s?= References: Date: Thu, 18 Mar 2021 14:17:42 +0100 In-Reply-To: ("=?UTF-8?Q?L=C3=A9o?= Le Bouter"'s message of "Wed, 17 Mar 2021 19:59:51 +0100") Message-ID: <87lfakr47d.fsf@gnu.org> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/27.1 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.18 Precedence: list X-BeenThere: bug-guix@gnu.org List-Id: Bug reports for GNU Guix List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: 47218@debbugs.gnu.org Errors-To: bug-guix-bounces+larch=yhetil.org@gnu.org Sender: "bug-Guix" X-Migadu-Flow: FLOW_IN ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=yhetil.org; s=key1; t=1616073496; h=from:from:sender:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding:resent-cc: resent-from:resent-sender:resent-message-id:in-reply-to:in-reply-to: references:references:list-id:list-help:list-unsubscribe: list-subscribe:list-post; bh=BzlCAcrgzmseYLV5W1/m+KLAWJ/r5c82e8tVKkD9V38=; b=c2dOZv5z96r3VeRoi+iK5Eilm1uI4zVsvI1jQBFD3R8Ni2PhHcFiHPVc2Zq1zeti1xMGvv av7ACNoIiFuhifsB1t35yEqiBhosbz3fWvlb7iFw43UusjTgpEdKRQV6jmIiNkmfztdXkA Zf8gVdsG+LI9gm4u36RnvmsWXMZR8mH6kC9A+BBEWRatzFBSoFwlr7K0nArqJ4t1V6kR8C +hS1GzZwTNNvZIxlEu8GVP8C4Ag8JcekXVlmJUC3CKZULKIqNmmBGbd+1NmTjSfbjP2qZl /AKhxOio2aIOJ62H6uZgA/Js6WlHNL1yayqlFnL6MVOaYQKwQRO3DHf7YpXgBQ== ARC-Seal: i=1; s=key1; d=yhetil.org; t=1616073496; a=rsa-sha256; cv=none; b=E3mMDcxBVUZ99Fzh6lQeOCIXHlxV0ullsb1S6HFBwVnLiRYOvVYnJA7F95n+d+zn/LdjRB SD2Wi45YnMAFJKMc17QhhG5zbFg+2u+Ct0BYj7/ouswHVTYe6Zi3kb5SLMwPp2UJC1ITys Exfi4VhIhcEAHGR7zjfSiWqi4mD+Mnao0D70P79yT/am0aYbvabxRqMCw1P175rpOzmMW1 AvAqzIOPu+uS7W+JAjP+xEXZInD8D/kmor7KNAmyDZOI8rRR8M5IpFYoiW0v8+qLo845Pw 5B05YN+gIzuC9xCMKJnX1N1hNyjLQZD4YErlAyVzNnacAv0kDUEoyaQOgpnN2g== ARC-Authentication-Results: i=1; aspmx1.migadu.com; dkim=none; spf=pass (aspmx1.migadu.com: domain of bug-guix-bounces@gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=bug-guix-bounces@gnu.org X-Migadu-Spam-Score: -2.41 Authentication-Results: aspmx1.migadu.com; dkim=none; dmarc=none; spf=pass (aspmx1.migadu.com: domain of bug-guix-bounces@gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=bug-guix-bounces@gnu.org X-Migadu-Queue-Id: 06593252AC X-Spam-Score: -2.41 X-Migadu-Scanner: scn0.migadu.com X-TUID: 7Qt1GAfPV0uW Hi L=C3=A9o, L=C3=A9o Le Bouter skribis: > Please see: > -=20 > https://www.gnu.org/software/libc/manual/html_mono/libc.html#Hardware-Cap= ability-Tunables > - https://www.phoronix.com/scan.php?page=3Dnews_item&px=3Dglibc-hwcaps-RFC > - https://gcc.gnu.org/onlinedocs/gcc/Function-Multiversioning.html > > This could help GNU Guix create binaries that include multiple code > paths for several CPU features in the same binary and selecting the > best at runtime when the binary is run. > > It is the best fit for GNU Guix because it means we can still use > substitutes and profit from specialized optimizations without > parameterized packages or each user adding "-march=3Dnative" to CFLAGS > (breaking reproducibility). For the record, we are well aware of these features and follow this very closely in particular in the context of Guix-HPC: https://hpc.guix.info/blog/2018/01/pre-built-binaries-vs-performance/ It seems to me that this bug report is not actionable though. Unless there are concrete steps you=E2=80=99d like to suggest, I propose to close = this issue. Thanks, Ludo=E2=80=99.