From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Thu, 24 Jul 2008 12:26:42 -0700 From: Andrew Morton Subject: Re: [Bugme-new] [Bug 11156] New: Old kernels copy memory faster than new Message-Id: <20080724122642.b8ef2ac6.akpm@linux-foundation.org> In-Reply-To: References: Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: linux-mm@kvack.org Cc: bugme-daemon@bugzilla.kernel.org, smal.root@gmail.com, Nick Piggin , Hugh Dickins List-ID: (switched to email. Please respond via emailed reply-to-all, not via the bugzilla web interface). On Thu, 24 Jul 2008 10:57:42 -0700 (PDT) bugme-daemon@bugzilla.kernel.org wrote: > http://bugzilla.kernel.org/show_bug.cgi?id=11156 > > Summary: Old kernels copy memory faster than new > Product: IO/Storage > Version: 2.5 > KernelVersion: 2.6.24, 2.6.25 > Platform: All > OS/Version: Linux > Tree: Mainline > Status: NEW > Severity: normal > Priority: P1 > Component: Block Layer > AssignedTo: axboe@kernel.dk > ReportedBy: smal.root@gmail.com > > > Latest working kernel version: 2.6.25 > Earliest failing kernel version: 2.6.24 > Distribution: Slackware 10-12 > > First machine: > CPU - AMD Athlon3600+(2______) > Chipset - nForce 6150(MCP51) > RAM - 3G DDR2 > Video - internal GeForce6150 > Kernel - 2.6.25.4(own built) > Copy speed - 1.7GByte/s > > on another kernel: > Kernel - 2.6.23.5(own built) > Copy speed - 43.5GByte/s > -------------------------------------------- > Second machine: > CPU - PII-350 > MB i440BX > RAM - 128M SDRAM > Video - 3DFX Voodoo3 > Kernel - 2.6.21.5(Vanila from slackware distribution) > Copy speed - 11.3GByte/s > > Steps to reproduce: > dd if=/dev/zero of=/dev/null bs=16M count=10000 > lol. OK, who did that? Perhaps ZERO_PAGE changes? -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org