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diff --git a/src/event/ngx_event_timer.c b/src/event/ngx_event_timer.c
index ababb819aa4be9229c3281785d2962cdda742e31..589de6d41282ed9cf91a13a253515f6866c3e2b2 100644 (file)
--- a/src/event/ngx_event_timer.c
+++ b/src/event/ngx_event_timer.c
@@ -17,6 +17,11 @@ ngx_mutex_t  *ngx_event_timer_mutex;
 ngx_thread_volatile ngx_rbtree_t  ngx_event_timer_rbtree;
 static ngx_rbtree_node_t          ngx_event_timer_sentinel;
 
+/*
+ * the event timer rbtree may contain the duplicate keys, however,
+ * it should not be a problem, because we use the rbtree to find
+ * a minimum timer value only
+ */
 
 ngx_int_t
 ngx_event_timer_init(ngx_log_t *log)