On Thu, Mar 25, 2021 at 08:49:26AM -0700, Darrick J. Wong wrote: > On Thu, Mar 25, 2021 at 04:41:29PM +0100, Christian Brauner wrote: > > Hey, > > > > I've been running xfstests on a v5.12-rc3 kernel using a swapfile: > > > > ubuntu@edfu|~ > > > cat /etc/fstab > > # /etc/fstab: static file system information. > > # > > # Use 'blkid' to print the universally unique identifier for a > > # device; this may be used with UUID= as a more robust way to name devices > > # that works even if disks are added and removed. See fstab(5). > > # > > # <file system> <mount point> <type> <options> <dump> <pass> > > # / was on /dev/sdb1 during curtin installation > > /dev/disk/by-uuid/f2c4df25-b55c-4d1b-95fa-059f72ef86eb / ext4 defaults 0 0 > > /swap.img none swap sw 0 0 > > > > where my rootfs is ext4: > > > > ubuntu@edfu|~ > > > findmnt | grep -i ext4 > > / /dev/sdb1 ext4 rw,relatime > > > > In addition to the /dev/sdb disk I have three other disks attached: > > > > ubuntu@edfu|~ > > > lsblk > > NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT > > loop0 7:0 0 55.5M 1 loop /snap/core18/1988 > > loop1 7:1 0 69.9M 1 loop /snap/lxd/19188 > > loop2 7:2 0 70.4M 1 loop /snap/lxd/19647 > > loop3 7:3 0 32.3M 1 loop /snap/snapd/11107 > > loop4 7:4 0 32.3M 1 loop /snap/snapd/11402 > > sda 8:0 0 931.5G 0 disk > > sdb 8:16 0 223.6G 0 disk > > └─sdb1 8:17 0 223.6G 0 part / > > sdc 8:32 0 279.5G 0 disk > > sdd 8:48 0 931.5G 0 disk > > > > I'm using two of them /dev/sdc and /dev/sdb for xfstests: > > > > ubuntu@edfu|~/src/git/xfstests > > > cat local.config > > # Ideally define at least these 4 to match your environment > > # The first 2 are required. > > # See README for other variables which can be set. > > # > > # Note: SCRATCH_DEV >will< get overwritten! > > > > export FSTYP=xfs > > export TEST_DEV=/dev/sdc > > export TEST_DIR=/mnt/test > > export SCRATCH_DEV=/dev/sdd > > export SCRATCH_MNT=/mnt/scratch > > > > when the system gets under load during test runs I assume it sometimes > > swaps and so sometimes I see the following messages pop up: > > > > > sudo journalctl | grep -i swapon > > Mar 21 00:00:58 edfu kernel: swapon: file has shared extents > > Mar 21 02:25:52 edfu kernel: swapon: file has unallocated extents > > Mar 21 21:38:12 edfu kernel: swapon: file has shared extents > > Mar 22 00:16:03 edfu kernel: swapon: file has unallocated extents > > Mar 23 11:49:46 edfu kernel: swapon: file has shared extents > > Mar 23 12:34:38 edfu kernel: swapon: file has unallocated extents > > > > I don't know enough about swapfiles to make any deep observations but I > > wonder what this can be caused by and whether this is something to worry > > about. > > That's ... probably just fstests performing regression tests of the > swapfile activation code to make sure that we only ever feed the mm > file extents that are mapped and stable. > > If you run only these tests: > generic/356 generic/357 generic/472 generic/493 generic/494 generic/495 > generic/496 generic/497 generic/554 generic/569 generic/570 > > Do you get the kernel messages right away? Those are the swapfile > stressors that I know about... Ah, that sounds good: generic/357 -> "swapon: file has shared extents" generic/495 -> "swapon: file has unallocated extents" Ok, I'm a bit careful since I've been bitten by the swapfile thing and wanted to make sure! Thanks for the pointer! Christian
