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=-3.2 required=3.0 tests=AWL,BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,RCVD_IN_DNSWL_HI,T_RP_MATCHES_RCVD shortcircuit=no autolearn=no 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 131A21FA7B for ; Fri, 16 Jun 2017 20:42:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751789AbdFPUmL (ORCPT ); Fri, 16 Jun 2017 16:42:11 -0400 Received: from cloud.peff.net ([104.130.231.41]:41755 "EHLO cloud.peff.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750903AbdFPUmL (ORCPT ); Fri, 16 Jun 2017 16:42:11 -0400 Received: (qmail 15593 invoked by uid 109); 16 Jun 2017 20:42:10 -0000 Received: from Unknown (HELO peff.net) (10.0.1.2) by cloud.peff.net (qpsmtpd/0.84) with SMTP; Fri, 16 Jun 2017 20:42:10 +0000 Received: (qmail 8595 invoked by uid 111); 16 Jun 2017 20:42:13 -0000 Received: from sigill.intra.peff.net (HELO sigill.intra.peff.net) (10.0.0.7) by peff.net (qpsmtpd/0.84) with SMTP; Fri, 16 Jun 2017 16:42:13 -0400 Received: by sigill.intra.peff.net (sSMTP sendmail emulation); Fri, 16 Jun 2017 16:42:08 -0400 Date: Fri, 16 Jun 2017 16:42:08 -0400 From: Jeff King To: Johannes Schindelin Cc: =?utf-8?B?w4Z2YXIgQXJuZmrDtnLDsA==?= Bjarmason , "brian m. carlson" , Adam Langley , Mike Hommey , Brandon Williams , Linus Torvalds , Jonathan Nieder , Git Mailing List , Stefan Beller , Jonathan Tan , Junio Hamano Subject: Re: Which hash function to use, was Re: RFC: Another proposed hash function transition plan Message-ID: <20170616204208.ak5twydrloxefm42@sigill.intra.peff.net> References: <20170615110518.ordr43idf2jluips@glandium.org> <20170615130145.stwbtict7q6oel7e@sigill.intra.peff.net> <87shj1ciy8.fsf@gmail.com> <20170615224110.kvrjs3lmwxcoqfaw@genre.crustytoothpaste.net> <20170616001738.affg4qby7y7yahos@genre.crustytoothpaste.net> <87y3ss8n4h.fsf@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org On Fri, Jun 16, 2017 at 03:24:19PM +0200, Johannes Schindelin wrote: > I have no doubt that Visual Studio Team Services, GitHub and Atlassian > will eventually end up with FPGAs for hash computation. So that's that. I actually doubt this from the GitHub side. Hash performance is not even on our radar as a bottleneck. In most cases the problem is touching uncompressed data _at all_, not computing the hash over it (so things like reusing on-disk deltas are really important). -Peff