From mboxrd@z Thu Jan 1 00:00:00 1970 From: "H. Peter Anvin" Subject: Re: [PATCH v3 0/3] automatically skip away from broken commits Date: Sat, 13 Jun 2009 12:57:38 -0700 Message-ID: <4A3404B2.5080700@zytor.com> References: <20090606043853.4031.78284.chriscool@tuxfamily.org> <7vtz2nlrfs.fsf@alter.siamese.dyndns.org> <200906110602.54861.chriscool@tuxfamily.org> <4A308B5D.2010704@zytor.com> <4A309083.9090907@zytor.com> <4A33F7E4.4020201@zytor.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Cc: Christian Couder , Christian Couder , Junio C Hamano , git@vger.kernel.org, Sam Vilain , Ingo Molnar To: Jakub Narebski X-From: git-owner@vger.kernel.org Sat Jun 13 21:58:03 2009 Return-path: Envelope-to: gcvg-git-2@gmane.org Received: from vger.kernel.org ([209.132.176.167]) by lo.gmane.org with esmtp (Exim 4.50) id 1MFZMZ-0000bW-2R for gcvg-git-2@gmane.org; Sat, 13 Jun 2009 21:58:03 +0200 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756968AbZFMT5x (ORCPT ); Sat, 13 Jun 2009 15:57:53 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754558AbZFMT5w (ORCPT ); Sat, 13 Jun 2009 15:57:52 -0400 Received: from terminus.zytor.com ([198.137.202.10]:48864 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754168AbZFMT5v (ORCPT ); Sat, 13 Jun 2009 15:57:51 -0400 Received: from mail.hos.anvin.org (c-98-210-181-100.hsd1.ca.comcast.net [98.210.181.100]) (authenticated bits=0) by terminus.zytor.com (8.14.3/8.14.1) with ESMTP id n5DJvgdL009406 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Sat, 13 Jun 2009 12:57:43 -0700 Received: from tazenda.hos.anvin.org (tazenda.hos.anvin.org [172.27.0.16]) by mail.hos.anvin.org (8.14.3/8.14.3) with ESMTP id n5DJvgq1024465; Sat, 13 Jun 2009 12:57:42 -0700 Received: from tazenda.hos.anvin.org (localhost.localdomain [127.0.0.1]) by tazenda.hos.anvin.org (8.14.3/8.13.6) with ESMTP id n5DJvc00006053; Sat, 13 Jun 2009 12:57:39 -0700 User-Agent: Thunderbird 2.0.0.14 (X11/20080501) In-Reply-To: X-Virus-Scanned: ClamAV 0.94.2/9464/Sat Jun 13 00:44:17 2009 on terminus.zytor.com X-Virus-Status: Clean Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org Archived-At: Jakub Narebski wrote: > > Why not borrow one of algorithms, e.g. taus[1] from GSL (GNU > Scientific Library)? > > If I understand "Random Number Generator Performance" chapter in GSL > Manual it is of comparable performance of the above BSD `rand` > generator, and is of simulation quality. > > [1] maximally equidistributed combined Tausworthe generator by L'Ecuyer > Interesting paper (the algorithm is on page 8): http://citeseerx.ist.psu.edu/viewdoc/download;jsessionid=F2BD39FF5C24221B424E12D9ED4E68B7?doi=10.1.1.43.4155&rep=rep1&type=pdf The reason I suggested SHA-1 is because we already have SHA-1 code involved (in fact, we even have a bunch of precalculated SHA-1s available to us) and performance matters not one iota in this application. -hpa -- H. Peter Anvin, Intel Open Source Technology Center I work for Intel. I don't speak on their behalf.