masonmark/zfs_bug_15526_reproducer.sh

## zfs_bug_15526_reproducer.sh
#!/bin/bash

# masonmark 2023-11-25
#
# This is my modified reproducer.sh for https://github.com/openzfs/zfs/issues/15526
# Original: https://gist.github.com/tonyhutter/d69f305508ae3b7ff6e9263b22031a84#file-reproducer-sh
#
# This is my modified reproducer script, which just fixes the typo in
# the example command and comments out the initial if block. I did
# not need zfs_bclone_enabled to be set (the orginial script got a
# "file not found" on my system, which is a physical machine running
# TrueNAS-SCALE-23.10.0.1 from a consumer SATA SSD. The machine is
# based on my kids' old gaming PC and has Intel Core i9 9900K CPU
# and a 3 NVMe SSDs, 5 SATA SSDs, and 7 spinning magnetic disks.
#
# This script reproduced the bug first try, and every try so far,
# within a few seconds, when run from the home director of the
# admin user, which is located on the default boot ZFS filesystem
# created by the TrueNAS SCALE installer.

# Run this script multiple times in parallel inside your pool's mount
# to reproduce https://github.com/openzfs/zfs/issues/15526.  Like:
#
# ./reproducer.sh & ./reproducer.sh & ./reproducer.sh & ./reproducer.sh & wait
#

#if [ $(cat /sys/module/zfs/parameters/zfs_bclone_enabled) != "1" ] ; then
#       echo "please set /sys/module/zfs/parameters/zfs_bclone_enabled = 1"
#       exit
#fi
#
# I commented the above out because this TrueNAS SCALE system is unmodified
# from what the installed configured, and I want to keep it that way for
# my testing. However, the reproducer apparently reproduces regardless of
# whether block-cloning is enabled; because I could reproduce this within the
# home directory of the admin user which is on boot-pool.
#
#   root@truenas:/mnt/slow# zpool get all | grep clon
#   big        bcloneused                     0                              -
#   big        bclonesaved                    0                              -
#   big        bcloneratio                    1.00x                          -
#   big        feature@block_cloning          enabled                        local
#   boot-pool  bcloneused                     0                              -
#   boot-pool  bclonesaved                    0                              -
#   boot-pool  bcloneratio                    1.00x                          -
#   boot-pool  feature@block_cloning          disabled                       local
#   fast       bcloneused                     1.71G                          -
#   fast       bclonesaved                    3.41G                          -
#   fast       bcloneratio                    2.99x                          -
#   fast       feature@block_cloning          active                         local
#   medium     bcloneused                     0                              -
#   medium     bclonesaved                    0                              -
#   medium     bcloneratio                    1.00x                          -
#   medium     feature@block_cloning          enabled                        local
#   slow       bcloneused                     1.46G                          -
#   slow       bclonesaved                    2.92G                          -
#   slow       bcloneratio                    2.99x                          -
#   slow       feature@block_cloning          active                         local
#   root@truenas:/mnt/slow#


prefix="reproducer_${BASHPID}_"
dd if=/dev/urandom of=${prefix}0 bs=1M count=1 status=none

echo "writing files"
end=1000
h=0
for i in `seq 1 2 $end` ; do
        let "j=$i+1"
        cp  ${prefix}$h ${prefix}$i
        cp --reflink=never ${prefix}$i ${prefix}$j
        let "h++"
done

echo "checking files"
for i in `seq 1 $end` ; do
        diff ${prefix}0 ${prefix}$i
done
	#!/bin/bash

	# masonmark 2023-11-25
	#
	# This is my modified reproducer.sh for https://github.com/openzfs/zfs/issues/15526
	# Original: https://gist.github.com/tonyhutter/d69f305508ae3b7ff6e9263b22031a84#file-reproducer-sh
	#
	# This is my modified reproducer script, which just fixes the typo in
	# the example command and comments out the initial if block. I did
	# not need zfs_bclone_enabled to be set (the orginial script got a
	# "file not found" on my system, which is a physical machine running
	# TrueNAS-SCALE-23.10.0.1 from a consumer SATA SSD. The machine is
	# based on my kids' old gaming PC and has Intel Core i9 9900K CPU
	# and a 3 NVMe SSDs, 5 SATA SSDs, and 7 spinning magnetic disks.
	#
	# This script reproduced the bug first try, and every try so far,
	# within a few seconds, when run from the home director of the
	# admin user, which is located on the default boot ZFS filesystem
	# created by the TrueNAS SCALE installer.

	# Run this script multiple times in parallel inside your pool's mount
	# to reproduce https://github.com/openzfs/zfs/issues/15526. Like:
	#
	# ./reproducer.sh & ./reproducer.sh & ./reproducer.sh & ./reproducer.sh & wait
	#

	#if [ $(cat /sys/module/zfs/parameters/zfs_bclone_enabled) != "1" ] ; then
	# echo "please set /sys/module/zfs/parameters/zfs_bclone_enabled = 1"
	# exit
	#fi
	#
	# I commented the above out because this TrueNAS SCALE system is unmodified
	# from what the installed configured, and I want to keep it that way for
	# my testing. However, the reproducer apparently reproduces regardless of
	# whether block-cloning is enabled; because I could reproduce this within the
	# home directory of the admin user which is on boot-pool.
	#
	# root@truenas:/mnt/slow# zpool get all \| grep clon
	# big bcloneused 0 -
	# big bclonesaved 0 -
	# big bcloneratio 1.00x -
	# big feature@block_cloning enabled local
	# boot-pool bcloneused 0 -
	# boot-pool bclonesaved 0 -
	# boot-pool bcloneratio 1.00x -
	# boot-pool feature@block_cloning disabled local
	# fast bcloneused 1.71G -
	# fast bclonesaved 3.41G -
	# fast bcloneratio 2.99x -
	# fast feature@block_cloning active local
	# medium bcloneused 0 -
	# medium bclonesaved 0 -
	# medium bcloneratio 1.00x -
	# medium feature@block_cloning enabled local
	# slow bcloneused 1.46G -
	# slow bclonesaved 2.92G -
	# slow bcloneratio 2.99x -
	# slow feature@block_cloning active local
	# root@truenas:/mnt/slow#


	prefix="reproducer_${BASHPID}_"
	dd if=/dev/urandom of=${prefix}0 bs=1M count=1 status=none

	echo "writing files"
	end=1000
	h=0
	for i in `seq 1 2 $end` ; do
	let "j=$i+1"
	cp ${prefix}$h ${prefix}$i
	cp --reflink=never ${prefix}$i ${prefix}$j
	let "h++"
	done

	echo "checking files"
	for i in `seq 1 $end` ; do
	diff ${prefix}0 ${prefix}$i
	done