From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail137.messagelabs.com (mail137.messagelabs.com [216.82.249.19]) by kanga.kvack.org (Postfix) with SMTP id 9BA2762012A for ; Wed, 4 Aug 2010 03:21:53 -0400 (EDT) From: "Kleen, Andi" Date: Wed, 4 Aug 2010 08:21:30 +0100 Subject: RE: scalability investigation: Where can I get your latest patches? Message-ID: References: <1278579387.2096.889.camel@ymzhang.sh.intel.com> <20100720031201.GC21274@amd> <1280883843.2125.20.camel@ymzhang.sh.intel.com> In-Reply-To: <1280883843.2125.20.camel@ymzhang.sh.intel.com> Content-Language: en-US Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Sender: owner-linux-mm@kvack.org To: "Zhang, Yanmin" , Nick Piggin Cc: "alexs.shi@intel.com" , "linux-mm@kvack.org" , "linux-fsdevel@vger.kernel.org" List-ID: > Issues: > 1) Compiling fails on a couple of file systems, such like > CONFIG_ISO9660_FS=3Dy. > 2) dbenchthreads has about 50% regression. We connect a JBOD of 12 > disks to > a machine. Start 4 dbench threads per disk. > We run the workload under a regular user account. If we run it under > root account, > we get 22% improvement instead of regression. > The root cause is ACL checking. With your patch, do_path_lookup firstly > goes through > rcu steps which including a exec permission checking. With ACL, the > __exec_permission > always fails. Then a later nameidata_drop_rcu often fails as dentry- > >d_seq is changed. I believe the latest version of Nick's patchkit has a likely fix for that. http://git.kernel.org/?p=3Dlinux/kernel/git/npiggin/linux-npiggin.git;a=3Dc= ommitdiff;h=3D9edd35f9aeafc8a5e1688b84cf4488a94898ca45 -Andi -- 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