/**
* Maintain the worker process map and notify the worker of an exited process.
* @param bool $block When true, method will block waiting for an exit signal
* @return void
*/
public function reap($block = false)
{
$map = $this->processes();
while (true) {
$pid = pcntl_wait($status, $block === true && $this->daemon->is('parent') ? NULL : WNOHANG);
if (!$pid || !isset($map[$pid])) {
break;
}
$alias = $map[$pid]->group;
$process = $this->processes[$alias][$pid];
$this->daemon->dispatch(array(Core_Daemon::ON_REAP), array($process, $status));
unset($this->processes[$alias][$pid]);
// Keep track of process churn -- failures within a processes min_ttl
// If too many failures of new processes occur inside a given interval, that's a problem.
// Raise a fatal error to prevent runaway process forking which can be very damaging to a server
if ($this->daemon->is('shutdown') || $process->runtime() >= $process->min_ttl) {
continue;
}
foreach ($this->failures as $key => $failure_time) {
if ($failure_time + self::CHURN_WINDOW < time()) {
unset($this->failures[$key]);
}
}
if (count($this->failures) > self::CHURN_LIMIT) {
$this->daemon->fatal_error("Recently forked processes are continuously failing. See error log for additional details.");
}
}
}
/**
* Dispatch ON_ERROR event, write an error message to the event log, and restart the worker.
*
* Part of the Worker API - Use from your worker to log a fatal error message and restart the current process.
*
* @param $message
* @return void
*/
public function fatal_error($message)
{
if ($this->daemon->is('parent')) {
$this->daemon->fatal_error("Fatal Error: {$message}", $this->alias);
} else {
$this->daemon->fatal_error("Fatal Error: {$message}\nWorker process will restart", $this->alias);
}
}
