diff --git a/lib/interval_tree_test.c b/lib/interval_tree_test.c
index bababcf..222c801 100644
--- a/lib/interval_tree_test.c
+++ b/lib/interval_tree_test.c
@@ -17,6 +17,7 @@
 __param(int, search_loops, 1000, "Number of iterations searching the tree");
 __param(bool, search_all, false, "Searches will iterate all nodes in the tree");
 
+__param(uint, max_endpoint, ~0, "Largest value for the interval's endpoint");
 
 static struct rb_root root = RB_ROOT;
 static struct interval_tree_node *nodes = NULL;
@@ -41,18 +42,20 @@
 	int i;
 
 	for (i = 0; i < nnodes; i++) {
-		u32 a = prandom_u32_state(&rnd);
-		u32 b = prandom_u32_state(&rnd);
-		if (a <= b) {
-			nodes[i].start = a;
-			nodes[i].last = b;
-		} else {
-			nodes[i].start = b;
-			nodes[i].last = a;
-		}
+		u32 b = (prandom_u32_state(&rnd) >> 4) % max_endpoint;
+		u32 a = (prandom_u32_state(&rnd) >> 4) % b;
+
+		nodes[i].start = a;
+		nodes[i].last = b;
 	}
+
+	/*
+	 * Limit the search scope to what the user defined.
+	 * Otherwise we are merely measuring empty walks,
+	 * which is pointless.
+	 */
 	for (i = 0; i < nsearches; i++)
-		queries[i] = prandom_u32_state(&rnd);
+		queries[i] = (prandom_u32_state(&rnd) >> 4) % max_endpoint;
 }
 
 static int interval_tree_test_init(void)