From mboxrd@z Thu Jan 1 00:00:00 1970 From: Thadeu Lima de Souza Cascardo Date: Tue, 11 May 2021 07:36:22 -0300 Subject: [LTP] [PATCH] mkfs: force block size to 1024 for ext3 and ext4 In-Reply-To: References: <20210510134739.37512-1-cascardo@canonical.com> Message-ID: <20210511103622.GC12149@mussarela> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: ltp@lists.linux.it On Tue, May 11, 2021 at 08:19:01AM +0200, Petr Vorel wrote: > Hi, > > > ext3 and ext4 filesystems will reserve at least 1024 blocks for the > > journal. With a blocksize of 4096, this will be 25% of the filesystem size > > without accounting for any other overhead. > Is that any actual problem? It causes the test to fail. mkfs01 2 TFAIL: 'mkfs -t ext4 /dev/loop0 16000' failed, unexpected size. The filesystem size is very small, 16K 1k blocks, and we test that there are at least 80% of that available. As I said, the journal takes at least 1024 blocks, and with 4k blocks, that is too much overhead. > > > /etc/mke2fs.conf will use 1024 block size for small filesystems, which are > > between 3M and 512M. However, on recent versions of Ubuntu, this > > configuration has changed and thet default blocksize is 4096 even for small > > filesystems. > > > Force the blocksize to 1024 on ext3 and ext4 filesystems, which will lead > > to the expected results, as journals will take only 1M. > > IMHO it'd be better to keep the default, because that covers what end users > actually use. One alternative to forcing the block size is accouting for the journal blocks, but, then, that needs to consider the block size. I think my approach is more simple. We could restrict it to the smaller 16M filesystem, though. What do you think? Thanks. Cascardo. > > Kind regards, > Petr