From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 25236C433EF for ; Wed, 25 May 2022 00:24:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234728AbiEYAYS (ORCPT ); Tue, 24 May 2022 20:24:18 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58952 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234347AbiEYAYS (ORCPT ); Tue, 24 May 2022 20:24:18 -0400 Received: from mail105.syd.optusnet.com.au (mail105.syd.optusnet.com.au [211.29.132.249]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id D10895BD21; Tue, 24 May 2022 17:24:16 -0700 (PDT) Received: from dread.disaster.area (pa49-181-2-147.pa.nsw.optusnet.com.au [49.181.2.147]) by mail105.syd.optusnet.com.au (Postfix) with ESMTPS id 5EA8D10E6CF4; Wed, 25 May 2022 10:24:15 +1000 (AEST) Received: from dave by dread.disaster.area with local (Exim 4.92.3) (envelope-from ) id 1nteov-00G1gy-4l; Wed, 25 May 2022 10:24:13 +1000 Date: Wed, 25 May 2022 10:24:13 +1000 From: Dave Chinner To: "Darrick J. Wong" Cc: Zorro Lang , Eryu Guan , fstests , xfs Subject: Re: [PATCH] xfs: test mkfs.xfs sizing of internal logs that Message-ID: <20220525002413.GT2306852@dread.disaster.area> References: <20220524234426.GQ2306852@dread.disaster.area> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Optus-CM-Score: 0 X-Optus-CM-Analysis: v=2.4 cv=VuxAv86n c=1 sm=1 tr=0 ts=628d7730 a=ivVLWpVy4j68lT4lJFbQgw==:117 a=ivVLWpVy4j68lT4lJFbQgw==:17 a=kj9zAlcOel0A:10 a=oZkIemNP1mAA:10 a=VwQbUJbxAAAA:8 a=7-415B0cAAAA:8 a=m0X_Dc9OxdgQlCnj0dMA:9 a=CjuIK1q_8ugA:10 a=AjGcO6oz07-iQ99wixmX:22 a=biEYGPWJfzWAr4FL6Ov7:22 Precedence: bulk List-ID: X-Mailing-List: linux-xfs@vger.kernel.org On Tue, May 24, 2022 at 04:49:30PM -0700, Darrick J. Wong wrote: > On Wed, May 25, 2022 at 09:44:26AM +1000, Dave Chinner wrote: > > On Tue, May 24, 2022 at 12:52:57PM -0700, Darrick J. Wong wrote: > > > From: Darrick J. Wong > > > > > > This is a regression test that exercises the mkfs.xfs code that creates > > > log sizes that are very close to the AG size when stripe units are in > > > play and/or when the log is forced to be in AG 0. > > > > > > Signed-off-by: Darrick J. Wong > > > --- > > > tests/xfs/843 | 56 +++++++++++++++++++++++++++++++++++++++++++++++++++++ > > > tests/xfs/843.out | 2 ++ > > > 2 files changed, 58 insertions(+) > > > create mode 100755 tests/xfs/843 > > > create mode 100644 tests/xfs/843.out > > > > > > diff --git a/tests/xfs/843 b/tests/xfs/843 > > > new file mode 100755 > > > index 00000000..3384b1aa > > > --- /dev/null > > > +++ b/tests/xfs/843 > > > @@ -0,0 +1,56 @@ > > > +#! /bin/bash > > > +# SPDX-License-Identifier: GPL-2.0 > > > +# Copyright (c) 2022 Oracle. All Rights Reserved. > > > +# > > > +# FS QA Test 843 > > > +# > > > +# Now that we've increased the default log size calculation, test mkfs with > > > +# various stripe units and filesystem sizes to see if we can provoke mkfs into > > > +# breaking. > > > +# > > > +. ./common/preamble > > > +_begin_fstest auto mkfs > > > + > > > +_cleanup() > > > +{ > > > + cd / > > > + rm -r -f $tmp.* $testfile > > > +} > > > > I'd omit this completely. > > > > > +# real QA test starts here > > > + > > > +# Modify as appropriate. > > > +_supported_fs xfs > > > +_require_test > > > + > > > +testfile=$TEST_DIR/a > > > +rm -f $testfile > > > + > > > +test_format() { > > > + local tag="$1" > > > + shift > > > + > > > + echo "$tag" >> $seqres.full > > > + $MKFS_XFS_PROG $@ -d file,name=$testfile &>> $seqres.full > > > + local res=$? > > > + test $res -eq 0 || echo "$tag FAIL $res" | tee -a $seqres.full > > > > What breakage are you trying to provoke? Just the log size > > calculation? If so, why do we need to actually write the filesystem > > to disk? Won't "-N" still calculate everything and fail if it's > > broken or quit with success without needing to write anything to > > disk? > > It will, but... > > > > +} > > > + > > > +# First we try various small filesystems and stripe sizes. > > > +for M in `seq 298 302` `seq 490 520`; do > > > + for S in `seq 32 4 64`; do > > > + test_format "M=$M S=$S" -dsu=${S}k,sw=1,size=${M}m > > > + done > > > +done > > > + > > > +# log so large it pushes the root dir into AG 1 > > > +test_format "log pushes rootdir into AG 1" -d agcount=3200,size=6366g -lagnum=0 > > ...this particular check in mkfs only happens after we allocate the root > directory, which an -N invocation doesn't do. Ok, so for this test can we drop the -N? We don't need to do 30 IOs and write 64MB logs for every config we test - I think there's ~35 * 8 invocations of test_format in the loop above before we get here... Also, why do we need a 6.3TB filesystem with 2.1GB AGs and a 2GB log to trigger this? That means we have to write 2GB to disk, plus ~20,000 write IOs for the AG headers and btree root blocks before we get to the failure case, yes? Why not just exercise the failure case with something like this: # mkfs.xfs -d agcount=2,size=64M -l size=8180b,agnum=0 -d file,name=test.img meta-data=test.img isize=512 agcount=2, agsize=8192 blks = sectsz=512 attr=2, projid32bit=1 = crc=1 finobt=1, sparse=1, rmapbt=0 = reflink=1 bigtime=0 inobtcount=0 data = bsize=4096 blocks=16384, imaxpct=25 = sunit=0 swidth=0 blks naming =version 2 bsize=4096 ascii-ci=0, ftype=1 log =internal log bsize=4096 blocks=8180, version=2 = sectsz=512 sunit=0 blks, lazy-count=1 realtime =none extsz=4096 blocks=0, rtextents=0 mkfs.xfs: root inode created in AG 1, not AG 0 # echo $? 1 # Otherwise I don't exactly understand what this specific case is supposed to be testing, so maybe some more explaining is necessary? Cheers, Dave. -- Dave Chinner david@fromorbit.com