From mboxrd@z Thu Jan 1 00:00:00 1970 From: bugme-daemon@bugzilla.kernel.org Subject: [Bug 11635] strange message in dmesg for IDE HDD: cannot use LBA48 DMA - PIO mode will be used for accessing sectors > 268435456 Date: Wed, 24 Sep 2008 03:18:07 -0700 (PDT) Message-ID: <20080924101807.9B313108056@picon.linux-foundation.org> References: Return-path: Received: from smtp1.linux-foundation.org ([140.211.169.13]:34419 "EHLO smtp1.linux-foundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752057AbYIXKS3 (ORCPT ); Wed, 24 Sep 2008 06:18:29 -0400 Received: from picon.linux-foundation.org (picon.linux-foundation.org [140.211.169.79]) by smtp1.linux-foundation.org (8.14.2/8.13.5/Debian-3ubuntu1.1) with ESMTP id m8OAI72x000474 for ; Wed, 24 Sep 2008 03:18:08 -0700 In-Reply-To: Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: linux-ide@vger.kernel.org http://bugzilla.kernel.org/show_bug.cgi?id=11635 ------- Comment #1 from sshtylyov@ru.mvista.com 2008-09-24 03:18 ------- (In reply to comment #0) > hdc: cannot use LBA48 DMA - PIO mode will be used for accessing sectors > > 268435456 The IDE core honestly warns you that the controller doesn't support DMA for accesses abobe 137 GB. Where's the problem? > hdc: 488397168 sectors (250059 MB) w/8192KiB Cache, CHS=30401/255/63 > hdparm output: > hdparm -Tt /dev/hdc output: > /dev/hdc: > Timing cached reads: 388 MB in 2.01 seconds = 193.07 MB/sec > Timing buffered disk reads: 142 MB in 3.03 seconds = 46.89 MB/sec > (I want to get something above 500MB/sec) 500 MB/s on disk reads?! That's totally wrong expectaion. What I am seeing seems quite adequate speed for UltraDMA. And cached reads don't measure disk transfer speed but rather your CPU bus/memory bandwidth. > May it help (googled) > i found that related info: > https://bugs.launchpad.net/ubuntu/+source/linux-source-2.6.20/+bug/119730 > http://osdir.com/ml/ide/2005-03/msg00064.html The latter reports DMA timeouts -- now that's an error indeed. But the report is against 2.6.11. :-) I suggest this to be resolved INVALID. -- Configure bugmail: http://bugzilla.kernel.org/userprefs.cgi?tab=email ------- You are receiving this mail because: ------- You are the assignee for the bug, or are watching the assignee.