manually control timeout, to dump trace data after hitting the limit

core/timeout.php

@@ -0,0 +1,32 @@
+<?php
+
+class TimeoutException extends RuntimeException
+{
+}
+
+class Timeout
+{
+    private $active;
+
+    public function set($seconds)
+    {
+        $this->active = true;
+        // declare(ticks = 1);
+        pcntl_signal(SIGALRM, [$this, 'handle'], true);
+        pcntl_alarm($seconds);
+        set_time_limit($seconds + 5);
+    }
+
+    public function clear()
+    {
+        set_time_limit(0);
+        $this->active = false;
+    }
+
+    public function handle($signal)
+    {
+        if ($this->active) {
+            throw new TimeoutException();
+        }
+    }
+}