--- a/src/event/modules/ngx_kqueue_module.c
+++ b/src/event/modules/ngx_kqueue_module.c
@@ -193,7 +193,8 @@ static ngx_int_t ngx_kqueue_add_event(ng
     ev->disabled = 0;
     ev->oneshot = (flags & NGX_ONESHOT_EVENT) ? 1 : 0;
 
-    if (nchanges > 0
+    if (ngx_thread_main()
+        && nchanges > 0
         && ev->index < (u_int) nchanges
         && ((uintptr_t) change_list[ev->index].udata & (uintptr_t) ~1)
                                                              == (uintptr_t) ev)
@@ -237,7 +238,8 @@ static ngx_int_t ngx_kqueue_del_event(ng
     ev->disabled = 0;
     ev->posted = 0;
 
-    if (nchanges > 0
+    if (ngx_thread_main()
+        && nchanges > 0
         && ev->index < (u_int) nchanges
         && ((uintptr_t) change_list[ev->index].udata & (uintptr_t) ~1)
                                                              == (uintptr_t) ev)
@@ -280,6 +282,7 @@ static ngx_int_t ngx_kqueue_set_event(ng
 {
     struct timespec    ts;
     ngx_connection_t  *c;
+    struct kevent     *kev, kv;
 
     c = ev->data;
 
@@ -287,7 +290,7 @@ static ngx_int_t ngx_kqueue_set_event(ng
                    "kevent set event: %d: ft:%d fl:%04X",
                    c->fd, filter, flags);
 
-    if (nchanges >= max_changes) {
+    if (ngx_thread_main() && nchanges >= max_changes) {
         ngx_log_error(NGX_LOG_WARN, ev->log, 0,
                       "kqueue change list is filled up");
 
@@ -302,40 +305,52 @@ static ngx_int_t ngx_kqueue_set_event(ng
         nchanges = 0;
     }
 
-    change_list[nchanges].ident = c->fd;
-    change_list[nchanges].filter = filter;
-    change_list[nchanges].flags = flags;
-    change_list[nchanges].udata = (void *) ((uintptr_t) ev | ev->instance);
+    kev = ngx_thread_main() ? &change_list[nchanges] : &kv;
+
+    kev->ident = c->fd;
+    kev->filter = filter;
+    kev->flags = flags;
+    kev->udata = (void *) ((uintptr_t) ev | ev->instance);
 
     if (filter == EVFILT_VNODE) {
-        change_list[nchanges].fflags = NOTE_DELETE|NOTE_WRITE|NOTE_EXTEND
-                                       |NOTE_ATTRIB|NOTE_RENAME
+        kev->fflags = NOTE_DELETE|NOTE_WRITE|NOTE_EXTEND
+                                 |NOTE_ATTRIB|NOTE_RENAME
 #if (__FreeBSD__ == 4 && __FreeBSD_version >= 430000) \
     || __FreeBSD_version >= 500018
-                                       |NOTE_REVOKE
+                                 |NOTE_REVOKE
 #endif
                                        ;
-        change_list[nchanges].data = 0;
+        kev->data = 0;
 
     } else {
 #if (HAVE_LOWAT_EVENT)
         if (flags & NGX_LOWAT_EVENT) {
-            change_list[nchanges].fflags = NOTE_LOWAT;
-            change_list[nchanges].data = ev->available;
+            kev->fflags = NOTE_LOWAT;
+            kev->data = ev->available;
 
         } else {
-            change_list[nchanges].fflags = 0;
-            change_list[nchanges].data = 0;
+            kev->fflags = 0;
+            kev->data = 0;
         }
 #else
-        change_list[nchanges].fflags = 0;
-        change_list[nchanges].data = 0;
+        kev->fflags = 0;
+        kev->data = 0;
 #endif
     }
 
-    ev->index = nchanges;
+    if (ngx_thread_main()) {
+        ev->index = nchanges;
+        nchanges++;
 
-    nchanges++;
+    } else {
+        ts.tv_sec = 0;
+        ts.tv_nsec = 0;
+
+        if (kevent(ngx_kqueue, &kv, 1, NULL, 0, &ts) == -1) {
+            ngx_log_error(NGX_LOG_ALERT, ev->log, ngx_errno, "kevent() failed");
+            return NGX_ERROR;
+        }
+    }
 
     return NGX_OK;
 }

--- a/src/event/ngx_event_posted.c
+++ b/src/event/ngx_event_posted.c
@@ -92,13 +92,16 @@ ngx_int_t ngx_event_thread_process_poste
                 || (ev->use_instance && ev->instance != ev->returned_instance))
             {
                 /*
-                 * the stale event from a file descriptor
-                 * that was just closed in this iteration
+                 * The stale event from a file descriptor that was just
+                 * closed in this iteration.  We use ngx_cycle->log
+                 * because ev->log may be already destoyed.
                  */
 
-                ngx_log_debug1(NGX_LOG_DEBUG_EVENT, ev->log, 0,
+                ngx_log_debug1(NGX_LOG_DEBUG_EVENT, ngx_cycle->log, 0,
                                "kevent: stale event " PTR_FMT, ev);
 
+                ngx_unlock(ev->lock);
+
                 ev = ev->next;
 
                 continue;

--- a/src/event/ngx_event_posted.h
+++ b/src/event/ngx_event_posted.h
@@ -8,9 +8,11 @@
 
 
 #define ngx_post_event(ev)                                                    \
+            if (!ev->posted) {                                                \
                 ev->next = (ngx_event_t *) ngx_posted_events;                 \
                 ngx_posted_events = ev;                                       \
-                ev->posted = 1;
+                ev->posted = 1;                                               \
+            }
 
 
 void ngx_event_process_posted(ngx_cycle_t *cycle);

--- a/src/event/ngx_event_timer.c
+++ b/src/event/ngx_event_timer.c
@@ -87,9 +87,11 @@ void ngx_event_expire_timers(ngx_msec_t 
             ev = (ngx_event_t *)
                            ((char *) node - offsetof(ngx_event_t, rbtree_key));
 
+#if (NGX_THREADS)
             if (ngx_trylock(ev->lock) == 0) {
                 break;
             }
+#endif
 
             ngx_log_debug2(NGX_LOG_DEBUG_EVENT, ev->log, 0,
                            "event timer del: %d: %d",
@@ -109,7 +111,9 @@ void ngx_event_expire_timers(ngx_msec_t 
 
             ev->timer_set = 0;
             ev->timedout = 1;
+#if (NGX_THREADS)
             ngx_unlock(ev->lock);
+#endif
 
             if (ngx_threaded) {
                 if (ngx_mutex_lock(ngx_posted_events_mutex) == NGX_ERROR) {

--- a/src/http/ngx_http_request.c
+++ b/src/http/ngx_http_request.c
@@ -1708,6 +1708,8 @@ void ngx_http_close_request(ngx_http_req
 
 void ngx_http_close_connection(ngx_connection_t *c)
 {
+    ngx_socket_t  fd;
+
     ngx_log_debug1(NGX_LOG_DEBUG_HTTP, c->log, 0,
                    "close http connection: %d", c->fd);
 
@@ -1737,15 +1739,24 @@ void ngx_http_close_connection(ngx_conne
         }
     }
 
-    if (ngx_close_socket(c->fd) == -1) {
-        ngx_log_error(NGX_LOG_ALERT, c->log, ngx_socket_errno,
-                      ngx_close_socket_n " failed");
-    }
+    fd = c->fd;
 
     c->fd = (ngx_socket_t) -1;
     c->data = NULL;
+    ngx_destroy_pool(c->pool);
 
-    ngx_destroy_pool(c->pool);
+    /*
+     * we has to clean the connection before the closing because another thread
+     * may reopen the same file descriptor before we clean the connection
+     */
+
+    if (ngx_close_socket(fd) == -1) {
+
+        /* we use ngx_cycle->log because c->log was in c->pool */
+
+        ngx_log_error(NGX_LOG_ALERT, ngx_cycle->log, ngx_socket_errno,
+                      ngx_close_socket_n " failed");
+    }
 
     return;
 }

--- a/src/os/unix/ngx_freebsd_rfork_thread.c
+++ b/src/os/unix/ngx_freebsd_rfork_thread.c
@@ -399,6 +399,10 @@ ngx_int_t ngx_mutex_dolock(ngx_mutex_t *
                     return NGX_ERROR;
                 }
 
+                ngx_log_debug2(NGX_LOG_DEBUG_CORE, m->log, 0,
+                               "mutex waked up " PTR_FMT " lock:%X",
+                               m, m->lock);
+
                 tries = 0;
                 old = m->lock;
                 continue;
@@ -505,6 +509,9 @@ ngx_int_t ngx_mutex_unlock(ngx_mutex_t *
 
             /* wake up the thread that waits on semaphore */
 
+            ngx_log_debug1(NGX_LOG_DEBUG_CORE, m->log, 0,
+                           "wake up mutex " PTR_FMT "", m);
+
             op.sem_num = 0;
             op.sem_op = 1;
             op.sem_flg = SEM_UNDO;

--- a/src/os/unix/ngx_thread.h
+++ b/src/os/unix/ngx_thread.h
@@ -77,6 +77,8 @@ static inline int ngx_gettid()
 }
 
 
+#define ngx_thread_main()   (ngx_gettid() == 0)
+
 
 #else /* use pthreads */
 
@@ -124,6 +126,10 @@ ngx_int_t ngx_cond_signal(ngx_cond_t *cv
 #define ngx_mutex_lock(m)     NGX_OK
 #define ngx_mutex_unlock(m)
 
+#define ngx_cond_signal(cv)
+
+#define ngx_thread_main()     1
+
 #endif