diff --git a/tests/xfs/016 b/tests/xfs/016
index 3407a4b1..aed37dca 100755
--- a/tests/xfs/016
+++ b/tests/xfs/016
@@ -44,10 +44,21 @@ _block_filter()
 
 _init()
 {
+    echo "*** determine log size"
+    local sz_mb=50
+    local dsize="-d size=${sz_mb}m"
+    local lsize="-l size=$(_scratch_find_xfs_min_logblocks $dsize)b"
+    local force_opts="$dsize $lsize"
+    _scratch_mkfs_xfs $force_opts >> $seqres.full 2>&1
+
+    # set log_size and log_size_bb globally
+    log_size_bb=`_log_size`
+    log_size=$((log_size_bb * 512))
+    echo "log_size_bb = $log_size_bb log_size = $log_size" >> $seqres.full
+
     echo "*** reset partition"
-    $here/src/devzero -b 2048 -n 50 -v 198 $SCRATCH_DEV
+    $here/src/devzero -b 2048 -n $sz_mb -v 198 $SCRATCH_DEV # write 0xc6
     echo "*** mkfs"
-    force_opts="-dsize=50m -lsize=$log_size"
     #
     # Do not discard blocks as we check for patterns in free space.
     # 
@@ -65,6 +76,9 @@ _init()
     . $tmp.mkfs
     [ $logsunit -ne 0 ] && \
         _notrun "Cannot run this test using log MKFS_OPTIONS specified"
+
+    # quotas generate extra log traffic so force it off
+    _qmount_option noquota
 }
 
 _log_traffic()
@@ -157,6 +171,7 @@ _check_corrupt()
 # get standard environment, filters and checks
 . ./common/rc
 . ./common/filter
+. ./common/quota
 
 # real QA test starts here
 _supported_fs xfs
@@ -164,10 +179,6 @@ _supported_os Linux
 
 rm -f $seqres.full
 
-# mkfs sizes
-log_size=3493888
-log_size_bb=`expr $log_size / 512`
-
 _require_scratch
 _init
 
@@ -188,18 +199,29 @@ echo "log sunit = $lsunit"			>>$seqres.full
 [ $head -eq 2 -o $head -eq $((lsunit/512)) ] || \
     _fail "!!! unexpected initial log position $head vs. $((lsunit/512))"
 
-# find how how many blocks per op for 100 ops
+# find how how many blocks per op for 200 ops
 # ignore the fact that it will also include an unmount record etc...
 # this should be small overall
 echo "    lots of traffic for sampling" >>$seqres.full
-sample_size_ops=100
+sample_size_ops=200
 _log_traffic $sample_size_ops
 head1=`_log_head`
 num_blocks=`expr $head1 - $head`
 blocks_per_op=`echo "scale=3; $num_blocks / $sample_size_ops" | bc`
+echo "log position = $head1; old log position: $head" >> $seqres.full
 echo "blocks_per_op = $blocks_per_op" >>$seqres.full
-num_expected_ops=`echo "$log_size_bb / $blocks_per_op" | bc`
+
+# Since this is a log wrapping test, it's critical to push the log head to
+# the point where it will wrap around within twenty rounds of log traffic.
+near_end_min=$(echo "$log_size_bb - (10 * $blocks_per_op / 1)" | bc)
+echo "near_end_min = $near_end_min" >>$seqres.full
+
+# Estimate the number of ops needed to get the log head close to but not past
+# near_end_min.  We'd rather fall short and have to step our way closer to the
+# end than run past the end.
+num_expected_ops=$(( 8 * $(echo "$log_size_bb / $blocks_per_op" | bc) / 10))
 echo "num_expected_ops = $num_expected_ops" >>$seqres.full
+
 num_expected_to_go=`echo "$num_expected_ops - $sample_size_ops" | bc`
 echo "num_expected_to_go = $num_expected_to_go" >>$seqres.full
 
@@ -208,13 +230,17 @@ _log_traffic $num_expected_to_go
 head=`_log_head`
 echo "log position = $head"                     >>$seqres.full
 
-# e.g. 3891
-near_end_min=`echo "0.95 * $log_size_bb" | bc | sed 's/\..*//'`
-echo "near_end_min = $near_end_min" >>$seqres.full
+# If we fell short of near_end_min, step our way towards it.
+while [ $head -lt $near_end_min ]; do
+	echo "    bump traffic from $head towards $near_end_min" >> $seqres.full
+	_log_traffic 10 > /dev/null 2>&1
+	head=$(_log_head)
+done
 
 [ $head -gt $near_end_min -a $head -lt $log_size_bb ] || \
     _fail "!!! unexpected near end log position $head"
 
+# Try to wrap the log, checking for corruption with each advance.
 for c in `seq 0 20`
 do
     echo "   little traffic"            >>$seqres.full
diff --git a/tests/xfs/016.out b/tests/xfs/016.out
index f7844cdf..f4c8f88d 100644
--- a/tests/xfs/016.out
+++ b/tests/xfs/016.out
@@ -1,4 +1,5 @@
 QA output created by 016
+*** determine log size
 *** reset partition
 Wrote 51200.00Kb (value 0xc6)
 *** mkfs
