Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758886Ab3GZNYP (ORCPT ); Fri, 26 Jul 2013 09:24:15 -0400 Received: from mx1.redhat.com ([209.132.183.28]:31482 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758868Ab3GZNYL (ORCPT ); Fri, 26 Jul 2013 09:24:11 -0400 Date: Fri, 26 Jul 2013 09:23:35 -0400 From: Vivek Goyal To: Jingbai Ma Cc: "kexec@lists.infradead.org" , "linux-kernel@vger.kernel.org" , "kumagai-atsushi@mxc.nes.nec.co.jp" , HATAYAMA Daisuke , "Eric W. Biederman" , cpw@sgi.com, "Mitchell, Lisa (MCLinux in Fort Collins)" , "Croxon, Nigel" , "Wang, Jin (Steven)" , Andrew Morton Subject: Re: makedumpfile 1.5.4 + kernel 3.11-rc2+ 4TB tests Message-ID: <20130726132335.GA27529@redhat.com> References: <51F260AF.7010409@hp.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <51F260AF.7010409@hp.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1285 Lines: 37 On Fri, Jul 26, 2013 at 07:42:39PM +0800, Jingbai Ma wrote: > 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. [CC Andrew]. Thanks Jingbai for testing results. Good to see that vmcore mmap() patches are helping. Thanks Vivek -- 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/