From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on dcvr.yhbt.net X-Spam-Level: X-Spam-ASN: AS31976 209.132.180.0/23 X-Spam-Status: No, score=-3.3 required=3.0 tests=AWL,BAYES_00, FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM,HEADER_FROM_DIFFERENT_DOMAINS, RCVD_IN_DNSWL_HI,RP_MATCHES_RCVD shortcircuit=no autolearn=ham autolearn_force=no version=3.4.0 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by dcvr.yhbt.net (Postfix) with ESMTP id 063992023D for ; Wed, 1 Mar 2017 22:06:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753456AbdCAWGI (ORCPT ); Wed, 1 Mar 2017 17:06:08 -0500 Received: from mout.gmx.net ([212.227.17.21]:64256 "EHLO mout.gmx.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751810AbdCAWF2 (ORCPT ); Wed, 1 Mar 2017 17:05:28 -0500 Received: from virtualbox ([37.201.192.48]) by mail.gmx.com (mrgmx103 [212.227.17.168]) with ESMTPSA (Nemesis) id 0McluX-1d0S052Vij-00HwLr; Wed, 01 Mar 2017 22:56:20 +0100 Date: Wed, 1 Mar 2017 22:56:18 +0100 (CET) From: Johannes Schindelin X-X-Sender: virtualbox@virtualbox To: Junio C Hamano cc: Linus Torvalds , Jeff King , Marc Stevens , Dan Shumow , Git Mailing List Subject: Re: [PATCH] Put sha1dc on a diet In-Reply-To: Message-ID: References: User-Agent: Alpine 2.20 (DEB 67 2015-01-07) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII X-Provags-ID: V03:K0:pexzc+5PwC/VRz7f1J85ja3heOwXpNd0qBHDwFo8aUkTAFI23wY 4JQqIk7aSPAHPi7aO8vuONGEFixlQyvHuKtYd96S6dnSDC3kTrnZ0CJ0AHFPjSFeFar25V9 0qr2PiT5HVcVdljETY19od8XqhS2ONHZ2wAFylPgOxt7Ooj50h4zRI6/fZbp/eQ/eN4jqOH 8SWUlo2qX8No56S3OrQMA== X-UI-Out-Filterresults: notjunk:1;V01:K0:uxog4OasyDE=:30aOPYieE22zVS7RugQFSG MGtlpzJCqlfKbf/rTgpfxInfV0fZFkYN78qnUnLErRGd9PIRDesDJlDFhT9cF4htkcK8YEe8N dMnpjKjxsf7p43UivFBdyPdx2k1k4jWh7ZRQoQ3zLSBt/PcdXRXWr+IAmM9G8vR+js475lvEC 1WF7fvm6NvTpDTjjZwEaMaQ74ddPwdnPXqK/nxTzFo6v30x0BQS0+5qGpBXIUNaz9p2n89NqT hPfa0niCVRk1l+uNKJPQcnxcvUboo7Ufo/C0ZJnpM7G2Vb0MpEFJ1dNkU3Ieo/ttTbHM+wD8O GEoLOvNwkXA5gGlStEiRQ1WIRo9O+7AufgSha5E+JS8jnzJXb0pZuWwUan84cd5irziZaTY+P 9B6jFAAn8nE7LhuTYVRr5NPcAXsP5jTyGblBNfArgTZcUOwXCwOA4jMpKHiBPrmr66rIoSzIF 4nsePPvqVFIoq/ORgZypeTYFne8z1dCYTK27n+XydJ9xBq0QCadRfxdwnNUYVTFah2ys3a9Gp JavZcEta4lSHyTJZdRS/fvCcyNFde+2JVUJlcAu4lbVkCwPNC8g2Xt7J6Og7KF01oAPIxNCmy KQAs9nlytDlNLDXN7f9jD/8ru/1KOwOhk5k7GAQjcaKmoiUM5SrRlA2S15Ar5SbLigzCky0lG A6VHRw7KdEil4xrQFlLLK0OYQdsuHV/Dre68ODuChG7Gsy+AlaTmWPq8OVBzz+C8IOeK7Jkau xI/dhdqW//8HsAlmkfQHMwVbXxmsd7QAPC9XeQ0vnKi3KFW3CAxim6U864045CYHMEeSZZ1fD T6ROYHWL+pfevGvdoqdTHF3fM/cnA== Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org Hi, On Wed, 1 Mar 2017, Junio C Hamano wrote: > Linus Torvalds writes: > > > That said, I think that it would be lovely to just default to > > USE_SHA1DC and just put the whole attack behind us. Yes, it's slower. > > No, it doesn't really seem to matter that much in practice. > > Yes. It would be a very good goal. So let me get this straight: not only do we now implicitly want to bump the required C compiler to C99 without any grace period worth mentioning [*1*], we are also all of a sudden no longer worried about a double digit percentage drop of speed [*2*]? Puzzled, Johannes Footnote *1*: I know, it is easy to forget that some developers cannot choose their tools, or even their hardware. In the past, we seemed to take appropriate care, though. Footnote *2*: With real-world repositories of notable size, that performance regression hurts. A lot. We just spent time to get the speed of SHA-1 down by a couple percent and it was a noticeable improvement here.