new file mode 100644
--- /dev/null
+++ b/src/event/ngx_event_timer.c
@@ -0,0 +1,165 @@
+
+/*
+ * Copyright (C) Igor Sysoev
+ */
+
+
+#include <ngx_config.h>
+#include <ngx_core.h>
+#include <ngx_event.h>
+
+
+#if (NGX_THREADS)
+ngx_mutex_t  *ngx_event_timer_mutex;
+#endif
+
+
+ngx_thread_volatile ngx_rbtree_t  *ngx_event_timer_rbtree;
+ngx_rbtree_t                       ngx_event_timer_sentinel;
+
+
+ngx_int_t ngx_event_timer_init(ngx_log_t *log)
+{
+    if (ngx_event_timer_rbtree) {
+#if (NGX_THREADS)
+        ngx_event_timer_mutex->log = log;
+#endif
+        return NGX_OK;
+    }
+
+    ngx_event_timer_rbtree = &ngx_event_timer_sentinel;
+
+#if (NGX_THREADS)
+    if (!(ngx_event_timer_mutex = ngx_mutex_init(log, 0))) {
+        return NGX_ERROR;
+    }
+#endif
+
+    return NGX_OK;
+}
+
+
+ngx_msec_t ngx_event_find_timer(void)
+{
+    ngx_msec_t     timer;
+    ngx_rbtree_t  *node;
+
+    if (ngx_event_timer_rbtree == &ngx_event_timer_sentinel) {
+        return NGX_TIMER_INFINITE;
+    }
+
+    if (ngx_mutex_lock(ngx_event_timer_mutex) == NGX_ERROR) {
+        return NGX_TIMER_ERROR;
+    }
+
+    node = ngx_rbtree_min((ngx_rbtree_t *) ngx_event_timer_rbtree,
+                          &ngx_event_timer_sentinel);
+
+    ngx_mutex_unlock(ngx_event_timer_mutex);
+
+    timer = (ngx_msec_t)
+         (node->key * NGX_TIMER_RESOLUTION -
+               ngx_elapsed_msec / NGX_TIMER_RESOLUTION * NGX_TIMER_RESOLUTION);
+#if 0
+                         (node->key * NGX_TIMER_RESOLUTION - ngx_elapsed_msec);
+#endif
+
+    return timer > 0 ? timer: 0 ;
+}
+
+
+void ngx_event_expire_timers(ngx_msec_t timer)
+{
+    ngx_event_t   *ev;
+    ngx_rbtree_t  *node;
+
+    if (timer < 0) {
+        /* avoid the endless loop if the time goes backward for some reason */
+        timer = 0;
+    }
+
+    for ( ;; ) {
+
+        if (ngx_event_timer_rbtree == &ngx_event_timer_sentinel) {
+            return;
+        }
+
+        if (ngx_mutex_lock(ngx_event_timer_mutex) == NGX_ERROR) {
+            return;
+        }
+
+        node = ngx_rbtree_min((ngx_rbtree_t *) ngx_event_timer_rbtree,
+                              &ngx_event_timer_sentinel);
+
+        if (node->key <= (ngx_msec_t)
+                         (ngx_old_elapsed_msec + timer) / NGX_TIMER_RESOLUTION)
+        {
+            ev = (ngx_event_t *)
+                           ((char *) node - offsetof(ngx_event_t, rbtree_key));
+
+#if (NGX_THREADS)
+
+            if (ngx_threaded && ngx_trylock(ev->lock) == 0) {
+
+                /*
+                 * We can not change the timer of the event that is been
+                 * handling by another thread.  And we can not easy walk
+                 * the rbtree to find a next expired timer so we exit the loop.
+                 * However it should be rare case when the event that is
+                 * been handling has expired timer.
+                 */
+
+                ngx_log_debug1(NGX_LOG_DEBUG_EVENT, ev->log, 0,
+                               "event " PTR_FMT " is busy in expire timers",
+                               ev);
+                break;
+            }
+#endif
+
+            ngx_log_debug2(NGX_LOG_DEBUG_EVENT, ev->log, 0,
+                           "event timer del: %d: %d",
+                            ngx_event_ident(ev->data), ev->rbtree_key);
+
+            ngx_rbtree_delete((ngx_rbtree_t **) &ngx_event_timer_rbtree,
+                              &ngx_event_timer_sentinel,
+                              (ngx_rbtree_t *) &ev->rbtree_key);
+
+            ngx_mutex_unlock(ngx_event_timer_mutex);
+
+#if (NGX_DEBUG)
+            ev->rbtree_left = NULL;
+            ev->rbtree_right = NULL;
+            ev->rbtree_parent = NULL;
+#endif
+
+            ev->timer_set = 0;
+
+#if (NGX_THREADS)
+            if (ngx_threaded) {
+                if (ngx_mutex_lock(ngx_posted_events_mutex) == NGX_ERROR) {
+                    return;
+                }
+
+                ev->posted_timedout = 1;
+                ngx_post_event(ev);
+
+                ngx_mutex_unlock(ngx_posted_events_mutex);
+
+                ngx_unlock(ev->lock);
+
+                continue;
+            }
+#endif
+
+            ev->timedout = 1;
+
+            ev->event_handler(ev);
+
+            continue;
+        }
+
+        break;
+    }
+
+    ngx_mutex_unlock(ngx_event_timer_mutex);
+}