From patchwork Sun Mar 2 07:17:49 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Darrick Wong X-Patchwork-Id: 325522 Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id C122C2C00A7 for ; Sun, 2 Mar 2014 18:17:53 +1100 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751503AbaCBHRx (ORCPT ); Sun, 2 Mar 2014 02:17:53 -0500 Received: from aserp1040.oracle.com ([141.146.126.69]:44240 "EHLO aserp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751467AbaCBHRw (ORCPT ); Sun, 2 Mar 2014 02:17:52 -0500 Received: from acsinet21.oracle.com (acsinet21.oracle.com [141.146.126.237]) by aserp1040.oracle.com (Sentrion-MTA-4.3.2/Sentrion-MTA-4.3.2) with ESMTP id s227Hpeg019889 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK); Sun, 2 Mar 2014 07:17:51 GMT Received: from aserz7022.oracle.com (aserz7022.oracle.com [141.146.126.231]) by acsinet21.oracle.com (8.14.4+Sun/8.14.4) with ESMTP id s227HovG021727 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Sun, 2 Mar 2014 07:17:50 GMT Received: from abhmp0012.oracle.com (abhmp0012.oracle.com [141.146.116.18]) by aserz7022.oracle.com (8.14.4+Sun/8.14.4) with ESMTP id s227HoS4004074; Sun, 2 Mar 2014 07:17:50 GMT Received: from localhost (/67.160.151.179) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Sat, 01 Mar 2014 23:17:50 -0800 Subject: [PATCH 11/32] mke2fs: set block_validity as a default mount option To: tytso@mit.edu, darrick.wong@oracle.com From: "Darrick J. Wong" Cc: linux-ext4@vger.kernel.org Date: Sat, 01 Mar 2014 23:17:49 -0800 Message-ID: <20140302071749.28217.59415.stgit@birch.djwong.org> In-Reply-To: <20140302071639.28217.57302.stgit@birch.djwong.org> References: <20140302071639.28217.57302.stgit@birch.djwong.org> User-Agent: StGit/0.15 MIME-Version: 1.0 X-Source-IP: acsinet21.oracle.com [141.146.126.237] Sender: linux-ext4-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-ext4@vger.kernel.org The block_validity mount option spot-checks block allocations against a bitmap of known group metadata blocks. This helps us to prevent self-inflicted catastrophic failures such as trying to "share" critical metadata (think bitmaps) with file data, which usually results in filesystem destruction. In order to test the overhead of the mount option, I re-used the speed tests in the metadata checksum testing script. In short, the program creates what looks like 15 copies of a kernel source tree, except that it uses fallocate to strip out the overhead of writing the file data so that we can focus on metadata overhead. On a 64G RAM disk, the overhead was generally about 0.9% and at most 1.6%. On a 160G USB disk, the overhead was about 0.8% and peaked at 1.2%. When I changed the test to write out files instead of merely fallocating space, the overhead was negligible. Signed-off-by: Darrick J. Wong --- misc/mke2fs.conf.in | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html diff --git a/misc/mke2fs.conf.in b/misc/mke2fs.conf.in index 178733f..3919f3b 100644 --- a/misc/mke2fs.conf.in +++ b/misc/mke2fs.conf.in @@ -1,6 +1,6 @@ [defaults] base_features = sparse_super,filetype,resize_inode,dir_index,ext_attr - default_mntopts = acl,user_xattr + default_mntopts = acl,user_xattr,block_validity enable_periodic_fsck = 0 blocksize = 4096 inode_size = 256