From unknown Fri Sep 05 18:47:56 2025 X-Loop: help-debbugs@gnu.org Subject: bug#8940: Evidence of bug in `random' Resent-From: Rafael D Sorkin Original-Sender: debbugs-submit-bounces@debbugs.gnu.org Resent-To: owner@debbugs.gnu.org Resent-CC: bug-gnu-emacs@gnu.org Resent-Date: Mon, 27 Jun 2011 05:12:01 +0000 Resent-Message-ID: Resent-Sender: help-debbugs@gnu.org X-GNU-PR-Message: report 8940 X-GNU-PR-Package: emacs X-GNU-PR-Keywords: To: 8940@debbugs.gnu.org X-Debbugs-Original-To: bug-gnu-emacs@gnu.org Reply-To: Rafael D Sorkin Received: via spool by submit@debbugs.gnu.org id=B.130915150931518 (code B ref -1); Mon, 27 Jun 2011 05:12:01 +0000 Received: (at submit) by debbugs.gnu.org; 27 Jun 2011 05:11:49 +0000 Received: from localhost ([127.0.0.1] helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.69) (envelope-from ) id 1Qb46u-0008CI-3b for submit@debbugs.gnu.org; Mon, 27 Jun 2011 01:11:49 -0400 Received: from eggs.gnu.org ([140.186.70.92]) by debbugs.gnu.org with esmtp (Exim 4.69) (envelope-from ) id 1Qb31r-0003aO-To for submit@debbugs.gnu.org; Mon, 27 Jun 2011 00:02:33 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Qb31l-0000wI-B4 for submit@debbugs.gnu.org; Mon, 27 Jun 2011 00:02:26 -0400 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on eggs.gnu.org X-Spam-Level: X-Spam-Status: No, score=0.6 required=5.0 tests=BAYES_00, RECEIVED_FROM_WINDOWS_HOST, T_RP_MATCHES_RCVD autolearn=no version=3.3.1 Received: from lists.gnu.org ([140.186.70.17]:56243) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Qb31l-0000wE-26 for submit@debbugs.gnu.org; Mon, 27 Jun 2011 00:02:25 -0400 Received: from eggs.gnu.org ([140.186.70.92]:44241) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Qb31j-0003l6-J8 for bug-gnu-emacs@gnu.org; Mon, 27 Jun 2011 00:02:24 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Qb31i-0000w0-9f for bug-gnu-emacs@gnu.org; Mon, 27 Jun 2011 00:02:23 -0400 Received: from perimeterinstitute.ca ([38.117.109.70]:15585) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Qb31h-0000vl-U5 for bug-gnu-emacs@gnu.org; Mon, 27 Jun 2011 00:02:21 -0400 Received: from mail.pi.local ([10.10.7.104]) by perimeterinstitute.ca with Microsoft SMTPSVC(6.0.3790.4675); Sun, 26 Jun 2011 23:40:19 -0400 Received: from mars.pi.local ([10.10.7.6]) by mail.pi.local over TLS secured channel with Microsoft SMTPSVC(6.0.3790.4675); Sun, 26 Jun 2011 23:40:18 -0400 Received: from rsorkin by mars.pi.local with local (Exim 4.69) (envelope-from ) id 1Qb2gM-0005pB-P6; Sun, 26 Jun 2011 23:40:18 -0400 From: Rafael D Sorkin X-Mailer: MH-E 8.2; nmh 1.2; GNU Emacs 23.1.1 Message-Id: Date: Sun, 26 Jun 2011 23:40:18 -0400 X-OriginalArrivalTime: 27 Jun 2011 03:40:18.0952 (UTC) FILETIME=[EF6E8080:01CC347B] X-detected-operating-system: by eggs.gnu.org: Windows 2000 SP4, XP SP1+ X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.6 (newer, 3) X-Received-From: 140.186.70.17 X-Spam-Score: -6.6 (------) X-Mailman-Approved-At: Mon, 27 Jun 2011 01:11:46 -0400 X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.11 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: debbugs-submit-bounces@debbugs.gnu.org Errors-To: debbugs-submit-bounces@debbugs.gnu.org X-Spam-Score: -6.6 (------) The following report refers to this version of emacs: GNU Emacs 23.2.1 (x86_64-pc-linux-gnu, GTK+ Version 2.24.4) of 2011-04-04 on crested, modified by Debian Hello, I'm sorry to submit a rather vague report, but I have found strong evidence of some sort of problem with the random number generator `random'. I see the difficulty only indirectly in some simulations I'm running. Results obtained from elisp's `random' disagree by over 6 sigma with results obtained from `mt-random' (the "mersenne twister") or from the built-in functions in both clisp and sbcl. Perhaps you could check for changes from earlier versions. The problem seems absent from version 22.1.1. Here's some info on the hardware from /proc/cpuinfo processor : 0 vendor_id : GenuineIntel cpu family : 6 model : 15 model name : Intel(R) Xeon(R) CPU E5335 @ 2.00GHz stepping : 11 cpu MHz : 1995.000 cache size : 4096 KB fpu : yes fpu_exception : yes cpuid level : 10 wp : yes flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss syscall lm constant_tsc arch\ _perfmon pebs bts rep_good nopl tsc_reliable aperfmperf pni ssse3 cx16 hypervisor lahf_lm dts bogomips : 3990.00 clflush size : 64 cache_alignment : 64 address sizes : 40 bits physical, 48 bits virtual power management: Thanks, ~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~ Rafael Sorkin Perimeter Institute for Theoretical Physics 31 Caroline Street North Waterloo, ON N2L 2Y5 Canada ~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~ From unknown Fri Sep 05 18:47:56 2025 MIME-Version: 1.0 X-Mailer: MIME-tools 5.427 (Entity 5.427) X-Loop: help-debbugs@gnu.org From: help-debbugs@gnu.org (GNU bug Tracking System) To: Rafael D Sorkin Subject: bug#8940: closed (Re: Evidence of bug in `random') Message-ID: References: <4E180E22.8010901@cs.ucla.edu> X-Gnu-PR-Message: they-closed 8940 X-Gnu-PR-Package: emacs Reply-To: 8940@debbugs.gnu.org Date: Sat, 09 Jul 2011 08:16:02 +0000 Content-Type: multipart/mixed; boundary="----------=_1310199362-31315-1" This is a multi-part message in MIME format... ------------=_1310199362-31315-1 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Your bug report #8940: Evidence of bug in `random' which was filed against the emacs package, has been closed. The explanation is attached below, along with your original report. If you require more details, please reply to 8940@debbugs.gnu.org. --=20 8940: http://debbugs.gnu.org/cgi/bugreport.cgi?bug=3D8940 GNU Bug Tracking System Contact help-debbugs@gnu.org with problems ------------=_1310199362-31315-1 Content-Type: message/rfc822 Content-Disposition: inline Content-Transfer-Encoding: 7bit Received: (at 8940-done) by debbugs.gnu.org; 9 Jul 2011 08:15:46 +0000 Received: from localhost ([127.0.0.1] helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.69) (envelope-from ) id 1QfShV-00088c-C4 for submit@debbugs.gnu.org; Sat, 09 Jul 2011 04:15:45 -0400 Received: from smtp.cs.ucla.edu ([131.179.128.62]) by debbugs.gnu.org with esmtp (Exim 4.69) (envelope-from ) id 1QfShT-00088M-5m for 8940-done@debbugs.gnu.org; Sat, 09 Jul 2011 04:15:44 -0400 Received: from localhost (localhost.localdomain [127.0.0.1]) by smtp.cs.ucla.edu (Postfix) with ESMTP id F211939E8119; Sat, 9 Jul 2011 01:15:36 -0700 (PDT) X-Virus-Scanned: amavisd-new at smtp.cs.ucla.edu Received: from smtp.cs.ucla.edu ([127.0.0.1]) by localhost (smtp.cs.ucla.edu [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id lefQL6RyEHXu; Sat, 9 Jul 2011 01:15:36 -0700 (PDT) Received: from [192.168.1.10] (pool-71-189-109-235.lsanca.fios.verizon.net [71.189.109.235]) by smtp.cs.ucla.edu (Postfix) with ESMTPSA id 4F4EE39E80F2; Sat, 9 Jul 2011 01:15:36 -0700 (PDT) Message-ID: <4E180E22.8010901@cs.ucla.edu> Date: Sat, 09 Jul 2011 01:15:30 -0700 From: Paul Eggert Organization: UCLA Computer Science Department User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.9.2.17) Gecko/20110516 Thunderbird/3.1.10 MIME-Version: 1.0 To: Rafael D Sorkin Subject: Re: Evidence of bug in `random' Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Spam-Score: -3.0 (---) X-Debbugs-Envelope-To: 8940-done Cc: 8940-done@debbugs.gnu.org X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.11 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: debbugs-submit-bounces@debbugs.gnu.org Errors-To: debbugs-submit-bounces@debbugs.gnu.org X-Spam-Score: -3.0 (---) Thanks for that bug report. Recently, I independently found severe nonrandomness in 'random' and installed a patch in the Emacs trunk as bzr 104596 . This patch should appear in the next major release of Emacs. Please give the patch a try. It may not be as good as the Mersenne twister etc., but it should be as good as Emacs 22 was. I'll mark this bug report as 'done' for now, but we can reopen it if the patch doesn't fix your problem. ------------=_1310199362-31315-1 Content-Type: message/rfc822 Content-Disposition: inline Content-Transfer-Encoding: 7bit Received: (at submit) by debbugs.gnu.org; 27 Jun 2011 05:11:49 +0000 Received: from localhost ([127.0.0.1] helo=debbugs.gnu.org) by debbugs.gnu.org with esmtp (Exim 4.69) (envelope-from ) id 1Qb46u-0008CI-3b for submit@debbugs.gnu.org; Mon, 27 Jun 2011 01:11:49 -0400 Received: from eggs.gnu.org ([140.186.70.92]) by debbugs.gnu.org with esmtp (Exim 4.69) (envelope-from ) id 1Qb31r-0003aO-To for submit@debbugs.gnu.org; Mon, 27 Jun 2011 00:02:33 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Qb31l-0000wI-B4 for submit@debbugs.gnu.org; Mon, 27 Jun 2011 00:02:26 -0400 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on eggs.gnu.org X-Spam-Level: X-Spam-Status: No, score=0.6 required=5.0 tests=BAYES_00, RECEIVED_FROM_WINDOWS_HOST, T_RP_MATCHES_RCVD autolearn=no version=3.3.1 Received: from lists.gnu.org ([140.186.70.17]:56243) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Qb31l-0000wE-26 for submit@debbugs.gnu.org; Mon, 27 Jun 2011 00:02:25 -0400 Received: from eggs.gnu.org ([140.186.70.92]:44241) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Qb31j-0003l6-J8 for bug-gnu-emacs@gnu.org; Mon, 27 Jun 2011 00:02:24 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Qb31i-0000w0-9f for bug-gnu-emacs@gnu.org; Mon, 27 Jun 2011 00:02:23 -0400 Received: from perimeterinstitute.ca ([38.117.109.70]:15585) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Qb31h-0000vl-U5 for bug-gnu-emacs@gnu.org; Mon, 27 Jun 2011 00:02:21 -0400 Received: from mail.pi.local ([10.10.7.104]) by perimeterinstitute.ca with Microsoft SMTPSVC(6.0.3790.4675); Sun, 26 Jun 2011 23:40:19 -0400 Received: from mars.pi.local ([10.10.7.6]) by mail.pi.local over TLS secured channel with Microsoft SMTPSVC(6.0.3790.4675); Sun, 26 Jun 2011 23:40:18 -0400 Received: from rsorkin by mars.pi.local with local (Exim 4.69) (envelope-from ) id 1Qb2gM-0005pB-P6; Sun, 26 Jun 2011 23:40:18 -0400 From: Rafael D Sorkin To: bug-gnu-emacs@gnu.org Subject: Evidence of bug in `random' X-Mailer: MH-E 8.2; nmh 1.2; GNU Emacs 23.1.1 Message-Id: Date: Sun, 26 Jun 2011 23:40:18 -0400 X-OriginalArrivalTime: 27 Jun 2011 03:40:18.0952 (UTC) FILETIME=[EF6E8080:01CC347B] X-detected-operating-system: by eggs.gnu.org: Windows 2000 SP4, XP SP1+ X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.6 (newer, 3) X-Received-From: 140.186.70.17 X-Spam-Score: -6.6 (------) X-Debbugs-Envelope-To: submit X-Mailman-Approved-At: Mon, 27 Jun 2011 01:11:46 -0400 X-BeenThere: debbugs-submit@debbugs.gnu.org X-Mailman-Version: 2.1.11 Precedence: list Reply-To: Rafael D Sorkin List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: debbugs-submit-bounces@debbugs.gnu.org Errors-To: debbugs-submit-bounces@debbugs.gnu.org X-Spam-Score: -6.6 (------) The following report refers to this version of emacs: GNU Emacs 23.2.1 (x86_64-pc-linux-gnu, GTK+ Version 2.24.4) of 2011-04-04 on crested, modified by Debian Hello, I'm sorry to submit a rather vague report, but I have found strong evidence of some sort of problem with the random number generator `random'. I see the difficulty only indirectly in some simulations I'm running. Results obtained from elisp's `random' disagree by over 6 sigma with results obtained from `mt-random' (the "mersenne twister") or from the built-in functions in both clisp and sbcl. Perhaps you could check for changes from earlier versions. The problem seems absent from version 22.1.1. Here's some info on the hardware from /proc/cpuinfo processor : 0 vendor_id : GenuineIntel cpu family : 6 model : 15 model name : Intel(R) Xeon(R) CPU E5335 @ 2.00GHz stepping : 11 cpu MHz : 1995.000 cache size : 4096 KB fpu : yes fpu_exception : yes cpuid level : 10 wp : yes flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss syscall lm constant_tsc arch\ _perfmon pebs bts rep_good nopl tsc_reliable aperfmperf pni ssse3 cx16 hypervisor lahf_lm dts bogomips : 3990.00 clflush size : 64 cache_alignment : 64 address sizes : 40 bits physical, 48 bits virtual power management: Thanks, ~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~ Rafael Sorkin Perimeter Institute for Theoretical Physics 31 Caroline Street North Waterloo, ON N2L 2Y5 Canada ~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~-~ ------------=_1310199362-31315-1--