Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757582Ab3GZLmp (ORCPT ); Fri, 26 Jul 2013 07:42:45 -0400 Received: from g4t0017.houston.hp.com ([15.201.24.20]:11730 "EHLO g4t0017.houston.hp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755325Ab3GZLmo (ORCPT ); Fri, 26 Jul 2013 07:42:44 -0400 Message-ID: <51F260AF.7010409@hp.com> Date: Fri, 26 Jul 2013 19:42:39 +0800 From: Jingbai Ma User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:10.0.12) Gecko/20130108 Thunderbird/10.0.12 MIME-Version: 1.0 To: "kexec@lists.infradead.org" , "linux-kernel@vger.kernel.org" CC: "kumagai-atsushi@mxc.nes.nec.co.jp" , HATAYAMA Daisuke , Vivek Goyal , "Eric W. Biederman" , cpw@sgi.com, "Mitchell, Lisa (MCLinux in Fort Collins)" , "Croxon, Nigel" , Jingbai Ma , "Wang, Jin (Steven)" Subject: makedumpfile 1.5.4 + kernel 3.11-rc2+ 4TB tests Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1087 Lines: 32 Hi, I have run some tests with makedumpfile 1.5.4 and upstream kernel 3.11-rc2+ on a machine with 4TB memory, here is testing results: Test environment: Machine: HP ProLiant DL980 G7 with 4TB RAM. CPU: Intel(R) Xeon(R) CPU E7- 2860 @ 2.27GHz (8 sockets, 10 cores) (Only 1 CPU was enabled the 2nd kernel) Kernel: 3.11.0-rc2+ (at patch b3a3a9c441e2c8f6b6760de9331023a7906a4ac6) crashkernel=384MB vmcore size: 4.0TB Dump file size: 15GB All measured time from debug message of makedumpfile. As a comparison, I also have tested makedumpfile 1.5.3. (all time in seconds) Excluding pages Copy data Total makedumpfile 1.5.3 468 1182 1650 makedumpfile 1.5.4 93 518 611 So it seems there is a great performance improvement by the mmap mechanism. -- Thanks, Jingbai Ma -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/