srv0start.c, srv0srv.c:

  If UNIV_SYNC_DEBUG was switched on, the error monitor thread could reserve a mutex BEFORE the sync debug system was initialized, and that caused a sync debug assertion in startup: move the 2 sec. sleep to a safer place; note that this is only heuristics, and in theory it can assert still

innobase/srv/srv0srv.c

@@ -2739,8 +2739,6 @@ srv_error_monitor_thread(
 
 	cnt++;
 
-	os_thread_sleep(2000000);
-
 	/* Try to track a strange bug reported by Harald Fuchs and others,
 	where the lsn seems to decrease at times */
 
@@ -2782,6 +2780,8 @@ srv_error_monitor_thread(
 	fflush(stderr);
 	fflush(stdout);
 
+	os_thread_sleep(2000000);
+
 	if (srv_shutdown_state < SRV_SHUTDOWN_LAST_PHASE) {
 
 		goto loop;

innobase/srv/srv0start.c

@@ -1512,12 +1512,13 @@ NetWare. */
 	srv_is_being_started = FALSE;
 
 #ifdef UNIV_DEBUG
-        /* Wait a while so that creates threads have time to suspend themselves
-	before we switch sync debugging on; otherwise a thread may execute
-	mutex_enter() before the checks are on, and mutex_exit() after the
-	checks are on. */
+        /* Wait a while so that the created threads have time to suspend
+	themselves before we switch sync debugging on; otherwise a thread may
+	execute mutex_enter() before the checks are on, and mutex_exit() after
+	the checks are on, which will cause an assertion failure in sync
+	debug. */
 
-        os_thread_sleep(2000000);
+        os_thread_sleep(3000000);
 #endif
 	sync_order_checks_on = TRUE;