Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756853Ab3IKTiG (ORCPT ); Wed, 11 Sep 2013 15:38:06 -0400 Received: from mx1.redhat.com ([209.132.183.28]:26700 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754387Ab3IKTiE (ORCPT ); Wed, 11 Sep 2013 15:38:04 -0400 Message-ID: <5230C5A7.2030206@redhat.com> Date: Wed, 11 Sep 2013 14:33:59 -0500 From: Eric Sandeen User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.8; rv:17.0) Gecko/20130801 Thunderbird/17.0.8 MIME-Version: 1.0 To: "Theodore Ts'o" , Andreas Dilger , Thavatchai Makphaibulchoke , T Makphaibulchoke , Al Viro , "linux-ext4@vger.kernel.org List" , Linux Kernel Mailing List , "linux-fsdevel@vger.kernel.org Devel" , aswin@hp.com, Linus Torvalds , aswin_proj@lists.hp.com Subject: Re: [PATCH v3 0/2] ext4: increase mbcache scalability References: <1374108934-50550-1-git-send-email-tmac@hp.com> <1378312756-68597-1-git-send-email-tmac@hp.com> <20130905023522.GA21268@thunk.org> <52285395.1070508@hp.com> <0787C579-7E2C-4864-B8F4-98816E1E50A2@dilger.ca> <5229C939.8030108@hp.com> <62D71A85-C7EE-4F5F-B481-5329F0282044@dilger.ca> <20130910210250.GH29237@thunk.org> <522FDFCC.1070007@redhat.com> <20130911113001.GB13315@thunk.org> <52309F27.8060008@redhat.com> In-Reply-To: <52309F27.8060008@redhat.com> X-Enigmail-Version: 1.5.2 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1810 Lines: 43 On 9/11/13 11:49 AM, Eric Sandeen wrote: > On 9/11/13 6:30 AM, Theodore Ts'o wrote: >> On Tue, Sep 10, 2013 at 10:13:16PM -0500, Eric Sandeen wrote: >>> >>> Above doesn't tell us the prevalence of various contexts on the actual system, >>> but they are all under 100 bytes in any case. >> >> OK, so in other words, on your system i_file_acl and i_file_acl_high >> (which is where we store the block # for the external xattr block), >> should always be zero for all inodes, yes? > > Oh, hum - ok, so that would have been the better thing to check (or at > least an additional thing). > > # find / -xdev -exec filefrag -x {} \; | awk -F : '{print $NF}' | sort | uniq -c > > Finds quite a lot that claim to have external blocks, but it seems broken: > > # filefrag -xv /var/lib/yum/repos/x86_64/6Server/epel > Filesystem type is: ef53 > File size of /var/lib/yum/repos/x86_64/6Server/epel is 4096 (1 block, blocksize 4096) > ext logical physical expected length flags > 0 0 32212996252 100 not_aligned,inline > /var/lib/yum/repos/x86_64/6Server/epel: 1 extent found > > So _filefrag_ says it has a block (at a 120T physical address not on my fs!) Oh, this is the special-but-not-documented "print inline extents in bytes not blocks" :( I'll send a patch to ignore inline extents on fiemap calls to make this easier, but in the meantime, neither my RHEL6 root nor my F17 root have any out-of-inode selinux xattrs on 256-byte-inode filesystems. So selinux alone should not be exercising mbcache much, if at all, w/ 256 byte inodes. -Eric -- 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/