diff --git a/tools/test/stress2/misc/buildkernel.sh b/tools/test/stress2/misc/buildkernel.sh
index 849a09b81439..e0aa85617f9b 100755
--- a/tools/test/stress2/misc/buildkernel.sh
+++ b/tools/test/stress2/misc/buildkernel.sh
@@ -1,63 +1,64 @@
 #!/bin/sh
 
 #
 # SPDX-License-Identifier: BSD-2-Clause
 #
 # Copyright (c) 2021 Peter Holm <pho@FreeBSD.org>
 #
 # 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.
 #
 
 # Buildkernel test with SU
 
 . ../default.cfg
 
 [ `id -u ` -ne 0 ] && echo "Must be root!" && exit 1
 
 [ -d /usr/src/sys ] || exit 0
 set -e
 mount | grep -q "on $mntpoint " && umount $mntpoint
 mdconfig -a -t swap -s 5g -u $mdstart
 newfs $newfs_flags md$mdstart > /dev/null
 mount /dev/md$mdstart $mntpoint
 set +e
 
 cd /usr/src
 export MAKEOBJDIRPREFIX=$mntpoint/obj
 export TMPDIR=$mntpoint/tmp
 mkdir $TMPDIR
 chmod 0777 $TMPDIR
 log=$mntpoint/log
 
 p=$((`sysctl -n hw.ncpu`+ 1))
+[ $p -gt 32 ] && p=32  # Arbitrary cap
 p=`jot -r 1 1 $p`
 echo "make -j $p buildkernel KERNCONF=GENERIC DESTDIR=$mntpoint" \
     "TARGET=amd64 TARGET_ARCH=amd64"
 make -j $p buildkernel KERNCONF=GENERIC DESTDIR=$mntpoint TARGET=amd64 \
     TARGET_ARCH=amd64 > $log 2>&1; s=$?
 [ $s -ne 0 ] && tail -50 $log
 
 while mount | grep -q "on $mntpoint "; do
 	umount $mntpoint || sleep 1
 done
 mdconfig -d -u $mdstart
 exit $s
diff --git a/tools/test/stress2/misc/buildworld.sh b/tools/test/stress2/misc/buildworld.sh
index 595b387c90ae..3b362ec7041a 100755
--- a/tools/test/stress2/misc/buildworld.sh
+++ b/tools/test/stress2/misc/buildworld.sh
@@ -1,66 +1,67 @@
 #!/bin/sh
 
 #
 # Copyright (c) 2015 EMC Corp.
 # 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.
 #
 
 # "panic: Invalid page 0xfffff8007f227cf0 on inact queue" seen.
 # https://people.freebsd.org/~pho/stress/log/buildworld.txt
 # Fixed by r289377
 
 . ../default.cfg
 
 [ `id -u ` -ne 0 ] && echo "Must be root!" && exit 1
 
 [ -d /usr/src/sys ] || exit 0
 [ `sysctl -n hw.physmem` -gt $(( 2 * 1024 * 1024 * 1024)) ] &&
     { echo "RAM must be clamped to 2GB or less for this test."; exit 0; }
 rm -f $diskimage
 [ `df -k $(dirname $diskimage) | tail -1 | awk '{print $4}'` -lt \
     $((3 * 1024 * 1024)) ] && { echo "Need 3GB on `dirname $diskimage`"; \
     exit 0; }
 mount | grep -q "on $mntpoint " && umount $mntpoint
 dd if=/dev/zero of=$diskimage bs=1m count=3k status=none
 trap "rm -f $diskimage" EXIT INT
 mdconfig -a -t vnode -f $diskimage -u $mdstart
 newfs $newfs_flags md$mdstart > /dev/null
 mount -o async /dev/md$mdstart $mntpoint
 
 cd /usr/src
 export MAKEOBJDIRPREFIX=$mntpoint/obj
 export TMPDIR=$mntpoint/tmp
 mkdir $TMPDIR
 chmod 0777 $TMPDIR
 
 p=$((`sysctl -n hw.ncpu`+ 1))
+[ $p -gt 32 ] && p=32  # Arbitrary cap
 timeout 20m make -i -j $p buildworld  DESTDIR=$mntpoint TARGET=amd64 \
     TARGET_ARCH=amd64 > /dev/null
 
 while mount | grep -q "on $mntpoint "; do
 	umount $mntpoint || sleep 1
 done
 checkfs /dev/md$mdstart || s=$?
 mdconfig -d -u $mdstart
 exit $s
diff --git a/tools/test/stress2/misc/buildworld2.sh b/tools/test/stress2/misc/buildworld2.sh
index 9c1eed97b7ea..3653cb1db5b4 100755
--- a/tools/test/stress2/misc/buildworld2.sh
+++ b/tools/test/stress2/misc/buildworld2.sh
@@ -1,57 +1,58 @@
 #!/bin/sh
 
 #
 # Copyright (c) 2015 EMC Corp.
 # 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.
 #
 
 # tmpfs version of buildworld.sh
 
 . ../default.cfg
 
 [ `id -u ` -ne 0 ] && echo "Must be root!" && exit 1
 
 [ -d /usr/src/sys ] || exit 0
 [ `swapinfo | wc -l` -eq 1 ] && exit 0
 [ `sysctl -n hw.physmem` -gt $(( 2 * 1024 * 1024 * 1024)) ] &&
     { echo "RAM must be clamped to 2GB or less."; exit 0; }
 mount | grep -q "on $mntpoint " && umount $mntpoint
 mount -t tmpfs tmpfs $mntpoint || exit 1
 
 cd /usr/src
 export MAKEOBJDIRPREFIX=$mntpoint/obj
 export TMPDIR=$mntpoint/tmp
 mkdir $TMPDIR
 chmod 0777 $TMPDIR
 
 p=$((`sysctl -n hw.ncpu`+ 1))
+[ $p -gt 32 ] && p=32  # Arbitrary cap
 make -j $p buildworld  DESTDIR=$mntpoint TARGET=amd64 TARGET_ARCH=amd64 \
     > /dev/null &
 sleep $((20 *  60))
 kill $!
 wait
 
 while mount | grep -q "on $mntpoint "; do
 	umount $mntpoint || sleep 1
 done
diff --git a/tools/test/stress2/misc/buildworld3.sh b/tools/test/stress2/misc/buildworld3.sh
index 0c660cae8eae..e3bce2764c0c 100755
--- a/tools/test/stress2/misc/buildworld3.sh
+++ b/tools/test/stress2/misc/buildworld3.sh
@@ -1,94 +1,95 @@
 #!/bin/sh
 
 #
 # SPDX-License-Identifier: BSD-2-Clause
 #
 # Copyright (c) 2018 Dell EMC Isilon
 #
 # 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.
 #
 
 # Buildworld / quota test scenario.
 
 # "panic: chkdquot: missing dquot" seen
 # https://people.freebsd.org/~pho/stress/log/kostik1113.txt
 # Fixed in r338798 + r338799
 
 . ../default.cfg
 
 [ `id -u ` -ne 0 ] && echo "Must be root!" && exit 1
 
 [ "`sysctl -in kern.features.ufs_quota`" != "1" ] && exit 0
 [ -d /usr/src/sys ] || exit 0
 mount | grep -q "on $mntpoint " && umount $mntpoint
 mdconfig -a -t swap -s 2g -u $mdstart
 newfs $newfs_flags md$mdstart > /dev/null
 
 export PATH_FSTAB=/tmp/fstab
 trap "rm -f $PATH_FSTAB" EXIT INT
 echo "/dev/md$mdstart $mntpoint ufs rw,userquota 2 2" > $PATH_FSTAB
 mount $mntpoint
 set `df -ik $mntpoint | tail -1 | awk '{print $4,$7}'`
 export QK=$(($1 / 2))
 export QI=$(($2 / 2))
 edquota -u -f $mntpoint -e \
     ${mntpoint}:$((QK - 50)):$QK:$((QI - 50 )):$QI $testuser
 quotaon $mntpoint
 mount | grep $mntpoint
 
 cd /usr/src
 export MAKEOBJDIRPREFIX=$mntpoint/obj
 export TMPDIR=$mntpoint/tmp
 mkdir $TMPDIR $MAKEOBJDIRPREFIX
 chmod 0777 $TMPDIR $MAKEOBJDIRPREFIX
 
 p=$((`sysctl -n hw.ncpu`+ 1))
+[ $p -gt 32 ] && p=32  # Arbitrary cap
 su $testuser -c \
     "make -i -j $p buildworld  DESTDIR=$mntpoint TARGET=amd64 \
     TARGET_ARCH=amd64 > /dev/null" &
 sleep 2
 start=`date +%s`
 while [ $((`date +%s` - start)) -lt 1200 ]; do
 	kill -0 $! > /dev/null 2>&1 || break
 	sleep 2
 done
 kill $! > /dev/null 2>&1
 # Let make run 50% of the time so quotaoff runs on an active FS
 [ `jot -r 1 0 1` -eq 1 ] &&
 	pkill -U$testuser make
 wait
 
 while ! quotaoff $mntpoint; do
 	sync
 	sleep 5
 done
 pgrep -q -U$testuser make && pkill -U$testuser make
 export tmp=/tmp/$(basename $0).$$
 quotacheck -v $mntpoint > $tmp 2>&1
 grep -q failed $tmp && { cat $tmp; s=1; }
 while mount | grep -q "on $mntpoint "; do
 	umount $mntpoint || sleep 1
 done
 checkfs /dev/md$mdstart || s=$?
 mdconfig -d -u $mdstart
 rm -f $PATH_FSTAB
 exit $s
diff --git a/tools/test/stress2/misc/buildworld4.sh b/tools/test/stress2/misc/buildworld4.sh
index 6c15a72a9dcb..d1d162120952 100755
--- a/tools/test/stress2/misc/buildworld4.sh
+++ b/tools/test/stress2/misc/buildworld4.sh
@@ -1,73 +1,74 @@
 #!/bin/sh
 
 #
 # SPDX-License-Identifier: BSD-2-Clause
 #
 # Copyright (c) 2018 Dell EMC Isilon
 #
 # 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.
 #
 
 # Buildworld test with SUJ
 # "fsync: giving up on dirty (error = 35): tag devfs, type VCHR" seen.
 
 . ../default.cfg
 
 [ `id -u ` -ne 0 ] && echo "Must be root!" && exit 1
 
 [ -d /usr/src/sys ] || exit 0
 rm -f $diskimage
 mount | grep -q "on $mntpoint " && umount $mntpoint
 mdconfig -a -t swap -s 5g -u $mdstart
 [ "$newfs_flags" = "-U" ] && newfs_flags="-j"
 newfs $newfs_flags md$mdstart > /dev/null
 mount /dev/md$mdstart $mntpoint
 mount | grep $mntpoint
 
 cd /usr/src
 export MAKEOBJDIRPREFIX=$mntpoint/obj
 export TMPDIR=$mntpoint/tmp
 mkdir $TMPDIR
 chmod 0777 $TMPDIR
 
 p=$((`sysctl -n hw.ncpu`+ 1))
+[ $p -gt 16 ] && p=16  # Arbitrary cap
 [ `sysctl -n vm.swap_total` -gt 0 ] && p=$((p * 4))
 p=`jot -r 1 1 $p`
 echo "make -i -j $p buildworld  DESTDIR=$mntpoint TARGET=amd64 "\
     "TARGET_ARCH=amd64"
 make -i -j $p buildworld  DESTDIR=$mntpoint TARGET=amd64 TARGET_ARCH=amd64 \
     > /dev/null &
 sleep 1
 start=`date +%s`
 while [ $((`date +%s` - start)) -lt 600 ]; do
 	kill -0 $! > /dev/null 2>&1 || break
 	sleep 30
 done
 kill $!  > /dev/null 2>&1
 wait
 
 while mount | grep -q "on $mntpoint "; do
 	umount $mntpoint || sleep 1
 done
 checkfs /dev/md$mdstart; s=$?
 mdconfig -d -u $mdstart
 exit $s
diff --git a/tools/test/stress2/misc/crossmp3.sh b/tools/test/stress2/misc/crossmp3.sh
index 5eecb936e900..32c625a1e4ad 100755
--- a/tools/test/stress2/misc/crossmp3.sh
+++ b/tools/test/stress2/misc/crossmp3.sh
@@ -1,111 +1,112 @@
 #!/bin/sh
 
 #
 # Copyright (c) 2014 EMC Corp.
 # 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.
 #
 
 # Parallel mount and umount of file systems
 # "panic: Bad link elm 0xfffff8052a20cc00 prev->next != elm" seen:
 # http://people.freebsd.org/~pho/stress/log/crossmp3.txt
 # Fixed in r269853
 
 # panic: softdep_waitidle: work added after flush:
 # http://people.freebsd.org/~pho/stress/log/crossmp3-2.txt, fixed by r273967.
 
 [ `id -u ` -ne 0 ] && echo "Must be root!" && exit 1
 
 . ../default.cfg
 
 CONT=/tmp/crossmp3.continue
 if [ $# -eq 0 ]; then
 	N=`sysctl -n hw.ncpu`
+	[ $N -gt 32 ] && N=32  # Arbitrary cap
 	usermem=`sysctl -n hw.usermem`
 	[ `sysctl -n vm.swap_total` -eq 0 ] && usermem=$((usermem / 2))
 	size=$((usermem / 1024 / 1024 / N))
 	echo "Using $N memory disks of size $size MB."
 
 	mounts=$N		# Number of parallel scripts
 
 	for i in `jot $mounts`; do
 		m=$(( i + mdstart - 1 ))
 		[ ! -d ${mntpoint}$m ] &&
 		    { mkdir ${mntpoint}$m; chmod 755 ${mntpoint}$m; }
 		mount | grep "${mntpoint}$m " | grep -q md$m &&
 		    umount ${mntpoint}$m
 		mdconfig -l | grep -q md$m && mdconfig -d -u $m
 
 		mdconfig -a -t swap -s ${size}m -u $m
 		newfs $newfs_flags md${m} > /dev/null 2>&1
 	done
 
 	# start the parallel tests
 	touch $CONT
 	for i in `jot $mounts`; do
 		m=$(( i + mdstart - 1 ))
 		./$0 $m &
 		./$0 find &
 	done
 	wait
 
 	for i in `jot $mounts`; do
 		m=$(( i + mdstart - 1 ))
 		while mount | grep -q "on ${mntpoint}$m "; do
 		    umount ${mntpoint}$m && break
 		    sleep 1
 		done
 		mdconfig -d -u $m
 	done
 	exit 0
 else
 	if [ $1 = find ]; then
 		while [ -f $CONT ]; do
 			find ${mntpoint}* -type f > /dev/null 2>&1
 		done
 	else
 		export runRUNTIME=20s
 		# The test: Parallel mount and unmounts
 		start=`date +%s`
 		for i in `jot 3`; do
 			m=$1
 			mount /dev/md${m} ${mntpoint}$m &&
 			   chmod 777 ${mntpoint}$m
 			export RUNDIR=${mntpoint}$m/stressX
 			export CTRLDIR=${mntpoint}$m/stressX.control
 			(cd ${mntpoint}$m && find . -delete)
 			su $testuser -c 'cd ..; ./run.sh disk.cfg' > \
 			    /dev/null 2>&1
 
 			while mount | grep -q "on ${mntpoint}$m "; do
 				opt=$([ $((`date '+%s'` % 2)) -eq 0 ] && echo "-f")
 				umount $opt ${mntpoint}$m > /dev/null 2>&1
 				[ -f $CONT ] || break 2
 			done
 			[ $((`date +%s` - start)) -gt 600 ] && 
 			    { echo "Timed out"; s=1; }
 		done
 		rm -f $CONT
 	fi
 	exit $s
 fi
diff --git a/tools/test/stress2/misc/crossmp4.sh b/tools/test/stress2/misc/crossmp4.sh
index e22f969b72bb..21d22bee69e5 100755
--- a/tools/test/stress2/misc/crossmp4.sh
+++ b/tools/test/stress2/misc/crossmp4.sh
@@ -1,106 +1,107 @@
 #!/bin/sh
 
 #
 # Copyright (c) 2014 EMC Corp.
 # 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.
 #
 
 # Parallel mount and umount of file systems. Nullfs version.
 
 # "panic: Lock (lockmgr) null not locked @ kern/vfs_default.c:523." seen.
 # http://people.freebsd.org/~pho/stress/log/kostik698.txt
 # Fixed by r269708.
 
 # Not fixed: https://people.freebsd.org/~pho/stress/log/kostik798.txt
 # https://people.freebsd.org/~pho/stress/log/kostik856.txt
 
 [ `id -u ` -ne 0 ] && echo "Must be root!" && exit 1
 
 . ../default.cfg
 
 N=`sysctl -n hw.ncpu`
+[ $N -gt 32 ] && N=32  # Arbitrary cap
 usermem=`sysctl -n hw.usermem`
 [ `swapinfo | wc -l` -eq 1 ] && usermem=$((usermem/100*80))
 size=$((usermem / 1024 / 1024 - 2))
 
 CONT=/tmp/crossmp4.continue
 mounts=$N		# Number of parallel scripts
 
 if [ $# -eq 0 ]; then
 	mount | grep "$mntpoint" | grep -q md && umount $mntpoint
 	mdconfig -l | grep -q md$mdstart &&  mdconfig -d -u $mdstart
 
 	mdconfig -a -t swap -s ${size}m -u $mdstart
 	newfs $newfs_flags md$mdstart > /dev/null 2>&1
 	mount /dev/md$mdstart $mntpoint
 
 	# start the parallel tests
 	for i in `jot $mounts`; do
 		m=$(( i + mdstart - 1 ))
 		./$0 $m &
 		./$0 find &
 	done
 
 	wait
 
 	while mount | grep -q "on $mntpoint "; do
 		umount $mntpoint > /dev/null 2>&1 || sleep 1
 	done
 	mdconfig -d -u $mdstart
 	exit 0
 else
 	touch $CONT
 	if [ $1 = find ]; then
 		while [ -f $CONT ]; do
 			find ${mntpoint}* -type f > /dev/null 2>&1
 		done
 	else
 		m=$1
 		set `df -ik $mntpoint | tail -1 | awk '{print $4,$7}'`
 		export KBLOCKS=$(($1 / N))
 		export INODES=$(($2 / N))
 		export runRUNTIME=1m
 		export INCARNATIONS=4
 		# The test: Parallel mount and unmounts
 		for i in `jot 4`; do
 			[ ! -d ${mntpoint}$m ] && mkdir ${mntpoint}$m
 			mount -t nullfs $mntpoint ${mntpoint}$m
 			mkdir -p ${mntpoint}$m/$m
 			chmod 777 ${mntpoint}$m/$m
 			export RUNDIR=${mntpoint}$m/$m/stressX
 			export CTRLDIR=${mntpoint}$m/$m/stressX.control
 			(cd  ${mntpoint}$m/$m && find . -delete)
 			su $testuser -c 'cd ..; ./run.sh disk.cfg' > \
 			    /dev/null 2>&1 &
 			sleep 30
 
 			while mount | grep -q "on ${mntpoint}$m "; do
 				opt=$([ $((`date '+%s'` % 2)) -eq 0 ] && echo "-f")
 				umount $opt ${mntpoint}$m > /dev/null 2>&1
 			done
 			wait
 		done
 		rm -f $CONT
 	fi
 fi
diff --git a/tools/test/stress2/misc/crossmp5.sh b/tools/test/stress2/misc/crossmp5.sh
index 038dea7ebe4f..6e504d9f20ad 100755
--- a/tools/test/stress2/misc/crossmp5.sh
+++ b/tools/test/stress2/misc/crossmp5.sh
@@ -1,97 +1,98 @@
 #!/bin/sh
 
 #
 # Copyright (c) 2014 EMC Corp.
 # 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.
 #
 
 # Variation of crossmp3.sh
 
 [ `id -u ` -ne 0 ] && echo "Must be root!" && exit 1
 
 . ../default.cfg
 
 N=`sysctl -n hw.ncpu`
+[ $N -gt 32 ] && N=32  # Arbitrary cap
 usermem=`sysctl -n hw.usermem`
 [ `swapinfo | wc -l` -eq 1 ] && usermem=$((usermem/100*80))
 size=$((usermem / 1024 / 1024 / N))
 
 mounts=$N		# Number of parallel scripts
 
 if [ $# -eq 0 ]; then
 	for i in `jot $mounts`; do
 		m=$(( i + mdstart - 1 ))
 		[ ! -d ${mntpoint}$m ] && mkdir ${mntpoint}$m
 		mount | grep "${mntpoint}$m " | grep -q md$m &&
 		    umount ${mntpoint}$m
 		mdconfig -l | grep -q md$m && mdconfig -d -u $m
 
 		mdconfig -a -t swap -s ${size}m -u $m
 		newfs $newfs_flags md${m} > /dev/null 2>&1
 	done
 
 	# start the parallel tests
 	for i in `jot $mounts`; do
 		m=$(( i + mdstart - 1 ))
 		./$0 $m &
 		./$0 find &
 	done
 
 	wait
 
 	for i in `jot $mounts`; do
 		m=$(( i + mdstart - 1 ))
 		mdconfig -d -u $m
 		rm -f $D$m
 	done
 	exit 0
 else
 	touch /tmp/crossmp.continue
 	if [ $1 = find ]; then
 		while [ -f /tmp/crossmp.continue ]; do
 			find ${mntpoint}* -type f > /dev/null 2>&1
 		done
 	else
 		# The test: Parallel mount and unmount
 		i=0
 		m=$1
 		start=`date +%s`
 		while [ $((`date +%s`- start)) -lt 300 ]; do
 			mount /dev/md${m} ${mntpoint}$m
 			chmod 777 ${mntpoint}$m
 			l=`jot -r 1 65535`
 			dd if=/dev/zero of=$mntpoint/$i bs=$l count=100 \
 		            status=none
 			rm -f $mntpoint/$i
 
 			while mount | grep -q "on ${mntpoint}$m "; do
 				opt=$([ $((`date '+%s'` % 2)) -eq 0 ] &&
 				    echo "-f")
 				umount $opt ${mntpoint}$m > /dev/null 2>&1
 			done
 			i=$((i + 1))
 		done
 		rm -f /tmp/crossmp.continue
 	fi
 fi
diff --git a/tools/test/stress2/misc/crossmp8.sh b/tools/test/stress2/misc/crossmp8.sh
index e877dfaf6d1c..eec5ba9bc7c1 100755
--- a/tools/test/stress2/misc/crossmp8.sh
+++ b/tools/test/stress2/misc/crossmp8.sh
@@ -1,124 +1,125 @@
 #!/bin/sh
 
 #
 # Copyright (c) 2015 EMC Corp.
 # 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.
 #
 
 # Variation of crossmp3.sh. fifos and sockets added to load.
 # Not really a cross mount point test, but a test of the old
 # non-directory use of the vnode v_un union.
 # mckusick@ suggested using fifos for this test.
 
 # "panic: mtx_lock() of spin mutex  @ ../kern/vfs_subr.c:512" seen.
 # https://people.freebsd.org/~pho/stress/log/crossmp8.txt
 # Fixed by r291671.
 
 [ `id -u ` -ne 0 ] && echo "Must be root!" && exit 1
 
 . ../default.cfg
 
 CONT=/tmp/crossmp8.continue
 N=`sysctl -n hw.ncpu`
+[ $N -gt 32 ] && N=32	# Arbitrary cap
 usermem=`sysctl -n hw.usermem`
 [ `swapinfo | wc -l` -eq 1 ] && usermem=$((usermem/100*80))
 size=$((usermem / 1024 / 1024 / N))
 
 mounts=$N		# Number of parallel scripts
 
 if [ $# -eq 0 ]; then
 	oldmx=`sysctl -n kern.maxvnodes`
 	trap "sysctl kern.maxvnodes=$oldmx > /dev/null" EXIT SIGINT
 	sysctl kern.maxvnodes=3072 > /dev/null
 
 	for i in `jot $mounts`; do
 		m=$((i + mdstart - 1))
 		[ ! -d ${mntpoint}$m ] &&
 		    { mkdir ${mntpoint}$m;  chmod 755 ${mntpoint}$m; }
 		mount | grep "${mntpoint}$m " | grep -q md$m &&
 		    umount ${mntpoint}$m
 		mdconfig -l | grep -q md$m && mdconfig -d -u $m
 
 		mdconfig -a -t swap -s ${size}m -u $m
 		newfs md${m} > /dev/null 2>&1
 	done
 
 	# start the parallel tests
 	touch $CONT
 	for i in `jot $mounts`; do
 		m=$((i + mdstart - 1))
 		./$0 $m &
 		./$0 find &
 	done
 	sleep 60
 	rm -f $CONT
 	../tools/killall.sh
 	wait
 
 	for i in `jot $mounts`; do
 		m=$((i + mdstart - 1))
 		while mount | grep -q "on ${mntpoint}$m "; do
 		    umount ${mntpoint}$m && break
 		    sleep 1
 		done
 		mdconfig -d -u $m
 	done
 	./cleanup.sh
 	exit 0
 else
 	if [ $1 = find ]; then
 		while [ -f $CONT ]; do
 			find ${mntpoint}* -maxdepth 1 -ls > /dev/null 2>&1
 			sleep .1
 		done
 	else
 		export RUNTIME=15s
 		export runRUNTIME=15s
 		# The test: Parallel mount and unmounts
 		start=`date '+%s'`
 		while [ $((`date '+%s'` - start)) -lt 300 ]; do
 			m=$1
 			mount /dev/md${m} ${mntpoint}$m &&
 			   chmod 777 ${mntpoint}$m
 			export RUNDIR=${mntpoint}$m/stressX
 			export CTRLDIR=${mntpoint}$m/stressX.control
 			export mkfifoLOAD=80
 			export socketLOAD=80
 			export TP="
 			testcases/mkfifo/mkfifo
 			testcases/mkdir/mkdir
 			"
 			(cd ${mntpoint}$m && find . -delete)
 			su $testuser -c 'cd ..; ./testcases/run/run $TP' > \
 			    /dev/null 2>&1
 
 			while mount | grep -q "on ${mntpoint}$m "; do
 				opt=$([ $((`date '+%s'` % 2)) -eq 0 ] && echo "-f")
 				umount $opt ${mntpoint}$m > /dev/null 2>&1
 				[ -f $CONT ] || break 2
 			done
 		done
 		rm -f $CONT
 	fi
 fi
diff --git a/tools/test/stress2/misc/gnop4.sh b/tools/test/stress2/misc/gnop4.sh
index f938dd3b790b..1b4da74266f6 100755
--- a/tools/test/stress2/misc/gnop4.sh
+++ b/tools/test/stress2/misc/gnop4.sh
@@ -1,76 +1,79 @@
 #!/bin/sh
 
 #
 # Copyright (c) 2016 Dell EMC
 # 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.
 #
 
 [ `id -u ` -ne 0 ] && echo "Must be root!" && exit 1
 
 # A 8k sector size test using buildworld.
 
 # "panic: DI already started" seen:
 # https://people.freebsd.org/~pho/stress/log/kostik1017.txt
 # Fixed by r322175
 
+# Seen with p=513: Threads stuck in "ffsrca"
+
 . ../default.cfg
 
 gigs=9
 [ $((`sysctl -n vm.swap_total` / 1024 / 1024 / 1024)) -lt $gigs ] && exit 0
 [ -d /usr/src/sys ] || exit 0
 
 kldstat | grep -q geom_nop || { gnop load 2>/dev/null || exit 0 &&
     notloaded=1; }
 gnop status || exit 1
 
 mount | grep $mntpoint | grep -q /dev/md && umount -f $mntpoint
 [ -c /dev/md$mdstart ] &&  mdconfig -d -u $mdstart
 
 set -e
 mdconfig -a -t swap -s ${gigs}g -u $mdstart
 gnop create -S 8k /dev/md$mdstart
 newfs $newfs_flags /dev/md$mdstart.nop > /dev/null
 mount /dev/md$mdstart.nop $mntpoint
 chmod 777 $mntpoint
 set +e
 
 (cd /usr; tar --exclude compile --exclude-vcs -cf - src) | \
     (cd $mntpoint; tar xf -)
 
 cd $mntpoint/src
 export MAKEOBJDIRPREFIX=$mntpoint/obj
 
 p=$((`sysctl -n hw.ncpu`+ 1))
+[ $p -gt 32 ] && p=32  # Temporary work around
 timeout 10m \
     make -i -j $p buildworld  DESTDIR=$mntpoint TARGET=amd64 \
     TARGET_ARCH=amd64 > /dev/null
 
 cd /
 while mount | grep $mntpoint | grep -q /dev/md; do
 	umount $mntpoint || sleep 1
 done
 gnop destroy /dev/md$mdstart.nop
 mdconfig -d -u $mdstart
 [ $notloaded ] && gnop unload
 exit 0
diff --git a/tools/test/stress2/misc/tmpfs13.sh b/tools/test/stress2/misc/tmpfs13.sh
index 29b44cbc9ad4..231c42033f9d 100755
--- a/tools/test/stress2/misc/tmpfs13.sh
+++ b/tools/test/stress2/misc/tmpfs13.sh
@@ -1,95 +1,96 @@
 #!/bin/sh
 
 #
 # Copyright (c) 2014 EMC Corp.
 # 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.
 #
 
 [ `id -u ` -ne 0 ] && echo "Must be root!" && exit 1
 
 # umount -f test scenario
 
 # "panic: deadlkres: possible deadlock detected..." seen.
 # http://people.freebsd.org/~pho/stress/log/tmpfs13.txt
 # Fixed by r269457.
 
 # "panic: vm_domainset_iter_first: Invalid domain 2" seen.
 # Fixed by r339075
 
 . ../default.cfg
 
 N=`sysctl -n hw.ncpu`
+[ $N -gt 32 ] && N=32  # Arbitrary cap
 usermem=`sysctl -n hw.usermem`
 [ `swapinfo | wc -l` -eq 1 ] && usermem=$((usermem/100*80))
 size=$((usermem / 1024 / 1024 / 2))
 
 export runRUNTIME=15m
 export RUNDIR=$mp1/stressX
 export CTRLDIR=$mp1/stressX.control
 export LOAD=80
 export symlinkLOAD=80
 export rwLOAD=80
 export TESTPROGS="
 testcases/lockf2/lockf2
 testcases/symlink/symlink
 testcases/openat/openat
 testcases/rw/rw
 testcases/fts/fts
 testcases/link/link
 testcases/lockf/lockf
 testcases/creat/creat
 testcases/mkdir/mkdir
 testcases/rename/rename
 testcases/mkfifo/mkfifo
 "
 
 for i in `jot $N 1`; do
 	eval mp$i=${mntpoint}$i
 done
 
 for i in `jot $N 1`; do
 	eval mp=\$mp$i
 	[ -d $mp ] || mkdir -p $mp
 	mount | grep $mp | grep -q tmpfs && umount -f $mp
 	mount  -o size=${size}m -t tmpfs tmpfs $mp
 	chmod 777 $mp
 	export RUNDIR=$mp/stressX
 	export CTRLDIR=$mp/stressX.control
 	su $testuser -c 'cd ..; ./testcases/run/run $TESTPROGS' > \
 	    /dev/null 2>&1 &
 done
 
 sleep 60
 
 for i in `jot $N 1`; do
 	eval mp=\$mp$i
 	while mount | grep "$mp " | grep -q tmpfs; do
 		umount -f $mp || sleep 1
 	done
 done
 ../tools/killall.sh
 while pgrep -q swap; do
 	pkill -9 swap
 done
 wait
diff --git a/tools/test/stress2/misc/zzbuildworld.sh b/tools/test/stress2/misc/zzbuildworld.sh
index 2104eb156c86..e1bf867d8d5f 100755
--- a/tools/test/stress2/misc/zzbuildworld.sh
+++ b/tools/test/stress2/misc/zzbuildworld.sh
@@ -1,54 +1,55 @@
 #!/bin/sh
 
 #
 # SPDX-License-Identifier: BSD-2-Clause
 #
 # Copyright (c) 2019 Dell EMC Isilon
 #
 # 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.
 #
 
 # Run a "make buildworld" as last test in stress2/misc.
 
 . ../default.cfg
 [ `id -u ` -ne 0 ] && echo "Must be root!" && exit 1
 kernel=`sysctl -n kern.bootfile`
 kerneldir=`strings -a $kernel | egrep -m 1 "$(hostname).*/compile/" | sed 's/.*://;s/ .*//'`
 [ -z "$kerneldir" ] && { echo "Can not find kerneldir"; exit 1; }
 src=`echo $kerneldir | sed 's#/sys/.*##'`
 [ ! -d $src ] && { echo "Can not find source in $src"; exit 1; }
 
 start=`date +%s`
 mount | grep -q "on $mntpoint " && exit 1
 mount -t tmpfs tmpfs $mntpoint
 top=$mntpoint
 export MAKEOBJDIRPREFIX=$top/obj
 export log=$top/buildworld.`date +%Y%m%dT%H%M`
 n=$((`sysctl -n hw.ncpu` + 1))
+[ $n -gt 32 ] && n=32  # Arbitrary cap
 cd $src
 make -j$n buildworld > $log 2>&1 && s=0 ||s=1
 grep  '\*\*\*' $log && s=2
 stop=`date +%s`
 echo "Elapsed `date -u -j -f '%s' '+%H:%M' $((stop - start))`"
 [ $s -ne 0 ] && { xz $log; cp -a $log.xz /tmp; }
 umount $mntpoint
 exit $s