Index: user/pho/stress2/misc/zfs5.sh
===================================================================
--- user/pho/stress2/misc/zfs5.sh	(revision 297917)
+++ user/pho/stress2/misc/zfs5.sh	(revision 297918)
@@ -1,69 +1,70 @@
 #!/bin/sh
 
 #
 # Copyright (c) 2009 Peter Holm <pho@FreeBSD.org>
 # All rights reserved.
 #
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions
 # are met:
 # 1. Redistributions of source code must retain the above copyright
 #    notice, this list of conditions and the following disclaimer.
 # 2. Redistributions in binary form must reproduce the above copyright
 #    notice, this list of conditions and the following disclaimer in the
 #    documentation and/or other materials provided with the distribution.
 #
 # THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 # ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 # IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 # ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 # FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 # DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 # OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 # HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 # LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 # OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 # SUCH DAMAGE.
 #
 # $FreeBSD$
 #
 
 # Simple zfs test of vdev as a file and snapshot clones
 
 [ `id -u ` -ne 0 ] && echo "Must be root!" && exit 1
 [ $((`sysctl -n hw.usermem` / 1024 / 1024 / 1024)) -le 3 ] && exit 0
 
 . ../default.cfg
 
 kldstat -v | grep -q zfs.ko  || { kldload zfs.ko; loaded=1; }
 
 d1=${diskimage}.1
 d2=${diskimage}.2
 
 dd if=/dev/zero of=$d1 bs=1m count=1k 2>&1 | egrep -v "records|transferred"
 dd if=/dev/zero of=$d2 bs=1m count=1k 2>&1 | egrep -v "records|transferred"
 
 [ -d /tank ] && rm -rf /tank
 zpool create tank $d1 $d2
 zfs create tank/test
 zfs set quota=100m tank/test
 
 export RUNDIR=/tank/test/stressX
 export runRUNTIME=10m
 (cd ..; ./run.sh vfs.cfg) &
 
 for i in `jot 20`; do
 	zfs snapshot tank/test@snap$i
 	zfs clone    tank/test@snap$i tank/snap$i
 done
 for i in `jot 20`; do
 	zfs destroy tank/snap$i
 	zfs destroy tank/test@snap$i
 done
 wait
 
 zfs destroy -r tank
 zpool destroy tank
 
 rm -rf $d1 $d2
 [ -n "$loaded" ] && kldunload zfs.ko
+exit 0
Index: user/pho/stress2/misc/zfs6.sh
===================================================================
--- user/pho/stress2/misc/zfs6.sh	(revision 297917)
+++ user/pho/stress2/misc/zfs6.sh	(revision 297918)
@@ -1,76 +1,79 @@
 #!/bin/sh
 
 #
 # Copyright (c) 2009 Peter Holm <pho@FreeBSD.org>
 # All rights reserved.
 #
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions
 # are met:
 # 1. Redistributions of source code must retain the above copyright
 #    notice, this list of conditions and the following disclaimer.
 # 2. Redistributions in binary form must reproduce the above copyright
 #    notice, this list of conditions and the following disclaimer in the
 #    documentation and/or other materials provided with the distribution.
 #
 # THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 # ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 # IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 # ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 # FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 # DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 # OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 # HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 # LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 # OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 # SUCH DAMAGE.
 #
 # $FreeBSD$
 #
 
-# Parallel mount / umount and snapshots. No problems seen.
+# Parallel mount / umount and snapshots. zpool hang seen:
+# https://people.freebsd.org/~pho/stress/log/zfs6.txt
 
 [ `id -u ` -ne 0 ] && echo "Must be root!" && exit 1
 [ $((`sysctl -n hw.usermem` / 1024 / 1024 / 1024)) -le 3 ] && exit 0
 
 . ../default.cfg
 
 kldstat -v | grep -q zfs.ko  || { kldload zfs.ko; loaded=1; }
 
 u1=$mdstart
 u2=$((u1 + 1))
 u3=$((u2 + 1))
 
 mdconfig -l | grep -q md${u1} && mdconfig -d -u $u1
 mdconfig -l | grep -q md${u2} && mdconfig -d -u $u2
 mdconfig -l | grep -q md${u3} && mdconfig -d -u $u3
 
 mdconfig -s 512m -u $u1
 mdconfig -s 512m -u $u2
 mdconfig -s 512m -u $u3
 
+zpool list | grep -q tank && zpool destroy tank
 [ -d /tank ] && rm -rf /tank
-zpool create tank raidz md$u1 md$u2 md$u3
-zfs create tank/test
+zpool create tank raidz md$u1 md$u2 md$u3 || exit 1
+zfs create tank/test || exit 1
 
 while true; do
 	zfs umount tank/test
 	zfs mount tank/test
 done &
 
 for i in `jot 5000`; do
 	touch /tank/test/f$i
 	zfs snapshot tank/test@$i
 	if [ $i -gt 5 ]; then
 		zfs destroy tank/test@$((i - 5))
 	fi
 done
 kill $!
 wait
 zfs destroy -r tank
 zpool destroy tank
 
 mdconfig -d -u $u1
 mdconfig -d -u $u2
 mdconfig -d -u $u3
 [ -n "$loaded" ] && kldunload zfs.ko
+exit 0