diff --git a/tests/xfs/167 b/tests/xfs/167
index ab0156f7..875bd318 100755
--- a/tests/xfs/167
+++ b/tests/xfs/167
@@ -62,6 +62,12 @@ _require_scratch
 _scratch_mkfs_xfs >/dev/null 2>&1
 _scratch_mount
 
+# fast devices can consume disk space at a rate of 1GB every 5s via the
+# background workload. With 50 test loops, at 1 second per loop, that means we
+# need at least 10GB of disk space to ensure this test will not fail with ENOSPC
+# errors.
+_require_fs_space $SCRATCH_MNT 10485760
+
 TEST_FILE=$SCRATCH_MNT/test_file
 TEST_PROG=$here/src/unwritten_sync
 LOOPS=50