Can't remember how I stumbled on this testcase, but mounting an ext3 filesystem with "-t ext4" and then resizing leads to trouble. With -o nodelalloc, the newly added space isn't seen by the allocator and we get ENOSPC for the extending writes in the script below. Without -o nodelalloc, the writes worked but I got an umount hang. Without -t ext4 (but letting ext4.ko handle the ext3 mount) it seems to work fine. Haven't looked into it much at all yet but wanted to put it out there for posterity. (script requires xfs_io, sorry, could be changed to dd I suppose) -Eric #!/bin/bash # Initial setup to create block devices prior to test: # /root/fallocate -l 100g fsfile # losetup /dev/loop0 fsfile # pvcreate /dev/loop0 # vgcreate VG /dev/loop0 COUNT=20 mkdir -p mnt umount mnt &>/dev/null lvremove -f /dev/VG/LV lvcreate -L 75G -n LV /dev/VG mkfs.ext3 -K /dev/VG/LV mount -t ext4 -o nodelalloc /dev/VG/LV mnt/ for I in `seq 1 $COUNT`; do mkdir mnt/dir$I; dd if=/dev/zero of=mnt/dir$I/file$I bs=1M count=4096; done echo "before growing:" df mnt/ umount mnt mount -t ext4 -o nodelalloc /dev/VG/LV mnt/ lvextend -L +5g /dev/VG/LV echo "growing:" resize2fs /dev/VG/LV echo "done growing:" df mnt/ # This gets ENOSPC for all of them echo "try extending files:" for I in `seq 1 $COUNT`; do xfs_io -f -F -c "pwrite -b 60m 4g 120m" mnt/dir$I/file$I; done df mnt/ umount mnt -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
