diff --git a/src/backend/tcop/postgres.c b/src/backend/tcop/postgres.c
index b185c1b..b5d7f80 100644
--- a/src/backend/tcop/postgres.c
+++ b/src/backend/tcop/postgres.c
@@ -3120,6 +3120,24 @@ check_stack_depth(void)
 	}
 }
 
+#ifdef DEBUG_STACK_DEPTH
+long last_stack_depth = 0;
+long high_stack_depth = 0;
+long high_stack_incr = 0;
+bool stack_depth_on_proc_exit = 0;
+
+/*
+ * on_proc_exit handler to log end of session
+ */
+static void
+log_stack_depth(int code, Datum arg)
+{
+	ereport(LOG,
+			(errmsg("disconnection: highest stack depth: %lu largest stack increment: %lu",
+					high_stack_depth, high_stack_incr)));
+}
+#endif
+
 bool
 stack_is_too_deep(void)
 {
@@ -3137,6 +3155,21 @@ stack_is_too_deep(void)
 	if (stack_depth < 0)
 		stack_depth = -stack_depth;
 
+#ifdef DEBUG_STACK_DEPTH
+	/* book-keeping for measuring STACK_DEPTH_SLOP */
+	if (stack_depth > high_stack_depth)
+		high_stack_depth = stack_depth;
+	if (stack_depth - last_stack_depth > high_stack_incr)
+		high_stack_incr = stack_depth - last_stack_depth;
+	last_stack_depth = stack_depth;
+
+	if (!stack_depth_on_proc_exit)
+	{
+		stack_depth_on_proc_exit = 1;
+		on_proc_exit(log_stack_depth, 0);
+	}
+#endif
+
 	/*
 	 * Trouble?
 	 *