From mboxrd@z Thu Jan 1 00:00:00 1970 From: Eric Sandeen Subject: Re: [PATCH, RFC] properly lock group descriptors before initializing Date: Wed, 16 Jul 2008 00:36:09 -0500 Message-ID: <487D88C9.4050501@redhat.com> References: <487D8671.2080307@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit To: ext4 development Return-path: Received: from mx1.redhat.com ([66.187.233.31]:50919 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751818AbYGPFgM (ORCPT ); Wed, 16 Jul 2008 01:36:12 -0400 Received: from int-mx1.corp.redhat.com (int-mx1.corp.redhat.com [172.16.52.254]) by mx1.redhat.com (8.13.8/8.13.8) with ESMTP id m6G5aBZb014696 for ; Wed, 16 Jul 2008 01:36:11 -0400 Received: from pobox-2.corp.redhat.com (pobox-2.corp.redhat.com [10.11.255.15]) by int-mx1.corp.redhat.com (8.13.1/8.13.1) with ESMTP id m6G5aACj000400 for ; Wed, 16 Jul 2008 01:36:10 -0400 Received: from liberator.sandeen.net (sebastian-int.corp.redhat.com [172.16.52.221]) by pobox-2.corp.redhat.com (8.13.1/8.13.1) with ESMTP id m6G5a9Ok032661 for ; Wed, 16 Jul 2008 01:36:10 -0400 In-Reply-To: <487D8671.2080307@redhat.com> Sender: linux-ext4-owner@vger.kernel.org List-ID: Eric Sandeen wrote: > I noticed when filling a 1T filesystem with 4 threads using the > fs_mark benchmark: > > fs_mark -d /mnt/test -D 256 -n 100000 -t 4 -s 20480 -F -S 0 > > that I occasionally got checksum mismatch errors: > > EXT4-fs error (device sdb): ext4_init_inode_bitmap: Checksum bad for group 6935 > > etc. I'd reliably get 4-5 of them during the run. > > It appears that the problem is likely a race to init the bg's > when the uninit_bg feature is enabled. > > With the patch below I was able to complete 2 runs with no errors > or warnings. However, I did hit a hang on one run that I can't yet > explain, so maybe this bears more inspection or testing. Crud hit it again, looks like it's my fault. So hold off on this one :) -Eric