diff --git a/tests/zfs-tests/tests/functional/cli_root/zpool_expand/zpool_expand_001_pos.ksh b/tests/zfs-tests/tests/functional/cli_root/zpool_expand/zpool_expand_001_pos.ksh
index b8bdfcfe78c2..c58e933f11be 100755
--- a/tests/zfs-tests/tests/functional/cli_root/zpool_expand/zpool_expand_001_pos.ksh
+++ b/tests/zfs-tests/tests/functional/cli_root/zpool_expand/zpool_expand_001_pos.ksh
@@ -1,168 +1,175 @@
 #! /bin/ksh -p
 #
 # CDDL HEADER START
 #
 # The contents of this file are subject to the terms of the
 # Common Development and Distribution License (the "License").
 # You may not use this file except in compliance with the License.
 #
 # You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 # or https://opensource.org/licenses/CDDL-1.0.
 # See the License for the specific language governing permissions
 # and limitations under the License.
 #
 # When distributing Covered Code, include this CDDL HEADER in each
 # file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 # If applicable, add the following below this CDDL HEADER, with the
 # fields enclosed by brackets "[]" replaced with your own identifying
 # information: Portions Copyright [yyyy] [name of copyright owner]
 #
 # CDDL HEADER END
 #
 
 #
 # Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
 # Use is subject to license terms.
 #
 
 #
 # Copyright (c) 2012, 2016 by Delphix. All rights reserved.
 # Copyright (c) 2018 by Lawrence Livermore National Security, LLC.
 #
 
 . $STF_SUITE/include/libtest.shlib
 . $STF_SUITE/tests/functional/cli_root/zpool_expand/zpool_expand.cfg
 
 #
 # DESCRIPTION:
 # Once zpool set autoexpand=on poolname, zpool can autoexpand by
 # Dynamic VDEV Expansion
 #
 #
 # STRATEGY:
 # 1) Create three vdevs (loopback, scsi_debug, and file)
 # 2) Create pool by using the different devices and set autoexpand=on
 # 3) Expand each device as appropriate
 # 4) Check that the pool size was expanded
 #
 # NOTE: Three different device types are used in this test to verify
 # expansion of non-partitioned block devices (loopback), partitioned
 # block devices (scsi_debug), and non-disk file vdevs.  ZFS volumes
 # are not used in order to avoid a possible lock inversion when
 # layering pools on zvols.
 #
 
 verify_runnable "global"
 
+# We override $org_size and $exp_size from zpool_expand.cfg to make sure we get
+# an expected free space value every time.  Otherwise, if we left it
+# configurable, the free space ratio to pool size ratio would diverge too much
+# much at low $org_size values.
+#
+org_size=$((1024 * 1024 * 1024))
+exp_size=$(($org_size * 2))
+
 function cleanup
 {
 	poolexists $TESTPOOL1 && destroy_pool $TESTPOOL1
 
 	if losetup -a | grep -q $DEV1; then
 		losetup -d $DEV1
 	fi
 
 	rm -f $FILE_LO $FILE_RAW
 
 	block_device_wait
 	unload_scsi_debug
 }
 
+# Wait for the size of a pool to autoexpand to $1 and the total free space to
+# expand to $2 (both values allowing a 10% tolerance).
+#
+# Wait for up to 10 seconds for this to happen (typically takes 1-2 seconds)
+#
+function wait_for_autoexpand
+{
+	typeset exp_new_size=$1
+	typeset exp_new_free=$2
+
+	for i in $(seq 1 10) ; do
+		typeset new_size=$(get_pool_prop size $TESTPOOL1)
+		typeset new_free=$(get_prop avail $TESTPOOL1)
+		# Values need to be within 90% of each other (10% tolerance)
+		if within_percent $new_size $exp_new_size 90 > /dev/null && \
+		    within_percent $new_free $exp_new_free 90 > /dev/null ; then
+			return
+		fi
+		sleep 1
+	done
+	log_fail "$TESTPOOL never expanded to $exp_new_size with $exp_new_free" \
+	    " free space (got $new_size with $new_free free space)"
+}
+
 log_onexit cleanup
 
 log_assert "zpool can be autoexpanded after set autoexpand=on on vdev expansion"
 
 for type in " " mirror raidz draid:1s; do
 	log_note "Setting up loopback, scsi_debug, and file vdevs"
 	log_must truncate -s $org_size $FILE_LO
 	DEV1=$(losetup -f)
 	log_must losetup $DEV1 $FILE_LO
 
 	load_scsi_debug $org_size_mb 1 1 1 '512b'
 	block_device_wait
 	DEV2=$(get_debug_device)
 
 	log_must truncate -s $org_size $FILE_RAW
 	DEV3=$FILE_RAW
 
 	# The -f is required since we're mixing disk and file vdevs.
 	log_must zpool create -f -o autoexpand=on $TESTPOOL1 $type \
 	    $DEV1 $DEV2 $DEV3
 
 	typeset autoexp=$(get_pool_prop autoexpand $TESTPOOL1)
 	if [[ $autoexp != "on" ]]; then
 		log_fail "zpool $TESTPOOL1 autoexpand should be on but is " \
 		    "$autoexp"
 	fi
 
 	typeset prev_size=$(get_pool_prop size $TESTPOOL1)
 	typeset zfs_prev_size=$(get_prop avail $TESTPOOL1)
 
 	# Expand each device as appropriate being careful to add an artificial
 	# delay to ensure we get a single history entry for each.  This makes
 	# is easier to verify each expansion for the striped pool case, since
 	# they will not be merged in to a single larger expansion.
 	log_note "Expanding loopback, scsi_debug, and file vdevs"
 	log_must truncate -s $exp_size $FILE_LO
 	log_must losetup -c $DEV1
-	sleep 3
 
 	echo "2" > /sys/bus/pseudo/drivers/scsi_debug/virtual_gb
 	echo "1" > /sys/class/block/$DEV2/device/rescan
 	block_device_wait
-	sleep 3
 
 	log_must truncate -s $exp_size $FILE_RAW
 	log_must zpool online -e $TESTPOOL1 $FILE_RAW
 
-	typeset expand_size=$(get_pool_prop size $TESTPOOL1)
-	typeset zfs_expand_size=$(get_prop avail $TESTPOOL1)
-
-	log_note "$TESTPOOL1 $type has previous size: $prev_size and " \
-	    "expanded size: $expand_size"
-	# compare available pool size from zfs
-	if [[ $zfs_expand_size -gt $zfs_prev_size ]]; then
-		# check for zpool history for the pool size expansion
-		if [[ $type == " " ]]; then
-			typeset expansion_size=$(($exp_size-$org_size))
-			typeset	size_addition=$(zpool history -il $TESTPOOL1 |\
-			    grep "pool '$TESTPOOL1' size:" | \
-			    grep "vdev online" | \
-			    grep -c "(+${expansion_size}")
-
-			if [[ $size_addition -ne 3 ]]; then
-				log_fail "pool $TESTPOOL1 has not expanded, " \
-				    "$size_addition/3 vdevs expanded"
-			fi
-		elif [[ $type == "mirror" ]]; then
-			typeset expansion_size=$(($exp_size-$org_size))
-			zpool history -il $TESTPOOL1 | \
-			    grep "pool '$TESTPOOL1' size:" | \
-			    grep "vdev online" | \
-			    grep -q "(+${expansion_size})" ||
-				log_fail "pool $TESTPOOL1 has not expanded"
-		elif [[ $type == "draid:1s" ]]; then
-			typeset expansion_size=$((2*($exp_size-$org_size)))
-			zpool history -il $TESTPOOL1 | \
-			    grep "pool '$TESTPOOL1' size:" | \
-			    grep "vdev online" | \
-			    grep -q "(+${expansion_size})" ||
-					log_fail "pool $TESTPOOL has not expanded"
-		else
-			typeset expansion_size=$((3*($exp_size-$org_size)))
-			zpool history -il $TESTPOOL1 | \
-			    grep "pool '$TESTPOOL1' size:" | \
-			    grep "vdev online" | \
-			    grep -q "(+${expansion_size})" ||
-					log_fail "pool $TESTPOOL has not expanded"
-		fi
-	else
-		log_fail "pool $TESTPOOL1 is not autoexpanded after vdev " \
-		    "expansion.  Previous size: $zfs_prev_size and expanded " \
-		    "size: $zfs_expand_size"
+
+	# The expected free space values below were observed at the time of
+	# this commit.  However, we know ZFS overhead will change over time,
+	# and thus we do not do an exact comparison to these values in
+	# wait_for_autoexpand.  Rather, we make sure the free space
+	# is within some small percentage threshold of these values.
+	typeset exp_new_size=$(($prev_size * 2))
+	if [[ "$type" == " " ]] ; then
+		exp_new_free=6045892608
+	elif [[ "$type" == "mirror" ]] ; then
+		exp_new_free=1945997312
+	elif [[ "$type" == "raidz" ]] ; then
+		exp_new_free=3977637338
+	elif [[ "$type" == "draid:1s" ]] then
+		exp_new_free=1946000384
 	fi
 
+	wait_for_autoexpand $exp_new_size $exp_new_free
+
+	expand_size=$(get_pool_prop size $TESTPOOL1)
+
+	log_note "$TESTPOOL1 '$type' grew from $prev_size -> $expand_size with" \
+	    "free space from $zfs_prev_size -> $(get_prop avail $TESTPOOL1)"
+
 	cleanup
 done
 
 log_pass "zpool can autoexpand if autoexpand=on after vdev expansion"