This problem is occuring for me as well with version 0.9.1. The issue is related to the fact that event_init() adds a "hidden" signal event to a static C function called signal_cb(). That event never appears to happen, or continues to reschedule itself.

I ended up fixing #7892, #7893, #7894, #7895. Here is a patch. Feel free to contact me if you have any problems.


Problems:
* Globals event_count_active and event_count were not initialized to 0. Initializing them fixed #7892 and #7894.
* Dispatch didn't check for initialization. Checking for initialization fixed #7893.
* Execution success/failure of call_user_func_ex were not returned by callback_to_php so that event_process_active would keep rescheduling bad events. Returning the result of call_user_func_ex and checking it in event_process_active for success fixed #7895. (My interpretation of the problem, but fix works for me).



diff -ruN event-0.9.1/event.c event-0.9.1-patched/event.c
--- event-0.9.1/event.c 2004-12-15 21:33:36.000000000 -0800
+++ event-0.9.1-patched/event.c 2007-02-11 16:38:28.000000000 -0800
@@ -191,7 +191,7 @@
 RB_GENERATE(event_tree, php_event, ev_timeout_node, php_event_compare);

 #if HAVE_SIGACTION
-static void signal_cb(int fd, short mask, void *arg TSRMLS_DC)
+int signal_cb(int fd, short mask, void *arg TSRMLS_DC)
 {
        int sig[32];
        struct php_event *ev;
@@ -208,6 +208,7 @@
                        }
                }
        } while (n == sizeof(sig));
+       return SUCCESS;
 }
 #endif

@@ -294,6 +295,9 @@
        }
 #endif

+       EVENT_G(event_count_active) = 0;
+       EVENT_G(event_count) = 0;
+
        RETURN_STRING(EVENT_G(evsel)->name, 1);
 }
 /* }}} */
@@ -626,6 +630,7 @@
        struct php_event *ev;
        struct event_list *activeq = NULL;
        int i;
+       int res;
        short ncalls;

        if (!EVENT_G(event_count_active))
@@ -637,7 +642,6 @@
                        break;
                }
        }
-
        for (ev = TAILQ_FIRST(activeq); ev; ev = TAILQ_FIRST(activeq)) {
                event_queue_remove(ev, EVLIST_ACTIVE TSRMLS_CC);

@@ -647,11 +651,13 @@
                while (ncalls) {
                        ncalls--;
                        ev->ev_ncalls = ncalls;
-                       (*ev->ev_callback)((int)ev->ev_fd, ev->ev_res, ev->ev_arg TSRMLS_CC);
+                       res = (*ev->ev_callback)((int)ev->ev_fd, ev->ev_res, ev->ev_arg TSRMLS_CC);
+                       if( res != SUCCESS )
+                               break;
                }

                /* re-add the event if its a persistent timeout only event */
-               if (ev->ev_events == (EV_TIMEOUT|EV_PERSIST)) {
+               if ( res == SUCCESS && ev->ev_events == (EV_TIMEOUT|EV_PERSIST)) {
                        event_add(ev, &ev->ev_timeout_interval TSRMLS_CC);
                }
        }
@@ -677,7 +683,11 @@
        struct timeval tv;
        int res, done;
        long flags = 0;
-
+
+       if (!EVENT_G(evsel)) {
+               php_error_docref(NULL TSRMLS_CC, E_WARNING, "Event enginte not initialized");
+               RETURN_FALSE;
+       }

        if (FAILURE == zend_parse_parameters(ZEND_NUM_ARGS() TSRMLS_CC, "|l", &flags)) {
                RETURN_LONG(-1);
@@ -767,8 +777,7 @@
        RETURN_LONG(res);
 }
 /* }}} */
-
-static void callback_to_php(int fd, short events, void *arg TSRMLS_DC)
+int callback_to_php(int fd, short events, void *arg TSRMLS_DC)
 {
        struct php_event *ev = (struct php_event*)arg;
        zval *retval = NULL;
@@ -793,8 +802,25 @@
        zval_ptr_dtor(&zevents);

        if (res != SUCCESS) {
-               php_error_docref(NULL TSRMLS_CC, E_WARNING, "callback failed");
+               if( EG(exception) )
+               {
+                       char ex_class_name[128];
+                       if( Z_TYPE_P(EG(exception)) == IS_OBJECT )
+                       {
+                               if (Z_TYPE_P(EG(exception)) == IS_OBJECT) {
+                                       strncpy(ex_class_name, Z_OBJ_CLASS_NAME_P(EG(exception)), 127);
+                                       ex_class_name[127] = '\0';
+                               } else {
+                                       strcpy(ex_class_name, "Unknown Exception");
+                               }
+                       }
+
+                       php_error_docref(NULL TSRMLS_CC, E_WARNING, "callback failed; %s thrown", ex_class_name);
+               }
+               else
+                       php_error_docref(NULL TSRMLS_CC, E_WARNING, "callback failed");
        }
+       return res;
 }

 static int event_set_for_php(int isnew, struct php_event *event, zval *zstream, long events, zval *cb, zval *cbarg TSRMLS_DC)
diff -ruN event-0.9.1/php_event_int.h event-0.9.1-patched/php_event_int.h
--- event-0.9.1/php_event_int.h 2004-12-15 19:30:18.000000000 -0800
+++ event-0.9.1-patched/php_event_int.h 2007-02-11 16:07:28.000000000 -0800
@@ -68,7 +68,7 @@

 #define TIMEOUT_DEFAULT                {5, 0}

-typedef void (*php_event_callback)(int, short, void *arg TSRMLS_DC);
+typedef int (*php_event_callback)(int, short, void *arg TSRMLS_DC);

 struct php_event {
 #ifdef PHP_WIN32

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