Backend/Frontend detection when checking for overload

diff --git a/boot.php b/boot.php
index 42767845c267b0089dcde159f91716ea8e78dabf..2db7d49d004dbff0263180c25863186dcec7482f 100644 (file)
--- a/boot.php
+++ b/boot.php
@@ -475,6 +475,7 @@ class App {
        public  $performance = array();
        public  $callstack = array();
        public  $theme_info = array();
+       public  $backend = true;
 
        public $nav_sel;
 
@@ -1111,6 +1112,80 @@ class App {
                return($this->is_friendica_app);
        }
 
+       /**
+        * @brief Checks if the site is called via a backend process
+        *
+        * This isn't a perfect solution. But we need this check very early.
+        * So we cannot wait until the modules are loaded.
+        *
+        * @return bool Is it a known backend?
+        */
+       function is_backend() {
+               $backend = array();
+               $backend[] = "_well_known";
+               $backend[] = "api";
+               $backend[] = "dfrn_notify";
+               $backend[] = "dfrn_poll";
+               $backend[] = "fetch";
+               $backend[] = "hcard";
+               $backend[] = "hostxrd";
+               $backend[] = "nodeinfo";
+               $backend[] = "noscrape";
+               $backend[] = "p";
+               $backend[] = "photo";
+               $backend[] = "photos";
+               $backend[] = "poco";
+               $backend[] = "post";
+               $backend[] = "proxy";
+               $backend[] = "pubsub";
+               $backend[] = "pubsubhubbub";
+               $backend[] = "receive";
+               $backend[] = "rsd_xml";
+               $backend[] = "salmon";
+               $backend[] = "statistics_json";
+               $backend[] = "xrd";
+
+               if (in_array($this->module, $backend))
+                       return(true);
+               else
+                       return($this->backend);
+       }
+
+       /**
+        * @brief Checks if the maximum number of database processes is reached
+        *
+        * @return bool Is the limit reached?
+        */
+       function max_processes_reached() {
+
+               // Is the function called statically?
+               if (!is_object($this))
+                       return(self::$a->max_processes_reached());
+
+               if ($this->is_backend()) {
+                       $process = "backend";
+                       $max_processes = get_config('system', 'max_processes_backend');
+                       if (intval($max_processes) == 0)
+                               $max_processes = 5;
+               } else {
+                       $process = "frontend";
+                       $max_processes = get_config('system', 'max_processes_frontend');
+                       if (intval($max_processes) == 0)
+                               $max_processes = 20;
+               }
+
+               $processlist = dbm::processlist();
+               if ($processlist["list"] != "") {
+                       logger("Processcheck: Processes: ".$processlist["amount"]." - Processlist: ".$processlist["list"], LOGGER_DEBUG);
+
+                       if ($processlist["amount"] > $max_processes) {
+                               logger("Processcheck: Maximum number of processes for ".$process." tasks (".$max_processes.") reached.", LOGGER_DEBUG);
+                               return true;
+                       }
+               }
+               return false;
+       }
+
        /**
         * @brief Checks if the maximum load is reached
         *
@@ -1118,14 +1193,26 @@ class App {
         */
        function maxload_reached() {
 
-               $maxsysload = intval(get_config('system', 'maxloadavg'));
-               if ($maxsysload < 1)
-                       $maxsysload = 50;
+               // Is the function called statically?
+               if (!is_object($this))
+                       return(self::$a->maxload_reached());
+
+               if ($this->is_backend()) {
+                       $process = "backend";
+                       $maxsysload = intval(get_config('system', 'maxloadavg'));
+                       if ($maxsysload < 1)
+                               $maxsysload = 50;
+               } else {
+                       $process = "frontend";
+                       $maxsysload = intval(get_config('system','maxloadavg_frontend'));
+                       if ($maxsysload < 1)
+                               $maxsysload = 50;
+               }
 
                $load = current_load();
                if ($load) {
                        if (intval($load) > $maxsysload) {
-                               logger('system: load '.$load.' too high.');
+                               logger('system: load '.$load.' for '.$process.' tasks ('.$maxsysload.') too high.');
                                return true;
                        }
                }

diff --git a/index.php b/index.php
index 943763a5110ce54c6dc9543ee2b0615e33ed523a..d2d3ecec3a371f4fa173627431678d1279bde392 100644 (file)
--- a/index.php
+++ b/index.php
@@ -19,6 +19,10 @@ require_once('object/BaseObject.php');
 $a = new App;
 BaseObject::set_app($a);
 
+// We assume that the index.php is called by a frontend process
+// The value is set to "true" by default in boot.php
+$a->backend = false;
+
 /**
  *
  * Load the configuration file which contains our DB credentials.
@@ -54,36 +58,12 @@ if(!$install) {
        load_config('config');
        load_config('system');
 
-       $processlist = dbm::processlist();
-       if ($processlist["list"] != "") {
-
-               logger("Processcheck: Processes: ".$processlist["amount"]." - Processlist: ".$processlist["list"], LOGGER_DEBUG);
-
-               $max_processes = get_config('system', 'max_processes_frontend');
-               if (intval($max_processes) == 0)
-                       $max_processes = 20;
-
-               if ($processlist["amount"] > $max_processes) {
-                       logger("Processcheck: Maximum number of processes for frontend tasks (".$max_processes.") reached.", LOGGER_DEBUG);
-                       system_unavailable();
-               }
-       }
-
-       $maxsysload_frontend = intval(get_config('system','maxloadavg_frontend'));
-       if($maxsysload_frontend < 1)
-               $maxsysload_frontend = 50;
-
-       $load = current_load();
-       if($load) {
-               if($load > $maxsysload_frontend) {
-                       logger('system: load ' . $load . ' too high. Service Temporarily Unavailable.');
-                       header($_SERVER["SERVER_PROTOCOL"].' 503 Service Temporarily Unavailable');
-                       header('Retry-After: 300');
-                       die("System is currently unavailable. Please try again later");
-               }
+       if ($a->max_processes_reached() OR $a->maxload_reached()) {
+               header($_SERVER["SERVER_PROTOCOL"].' 503 Service Temporarily Unavailable');
+               header('Retry-After: 300');
+               die("System is currently unavailable. Please try again later");
        }
 
-
        if (get_config('system','force_ssl') AND ($a->get_scheme() == "http") AND
                (intval(get_config('system','ssl_policy')) == SSL_POLICY_FULL) AND
                (substr($a->get_baseurl(), 0, 8) == "https://")) {
@@ -114,9 +94,12 @@ load_translation_table($lang);
  *
  */
 
-$stamp1 = microtime(true);
-session_start();
-$a->save_timestamp($stamp1, "parser");
+// Exclude the backend processes from the session management
+if (!$a->is_backend()) {
+       $stamp1 = microtime(true);
+       session_start();
+       $a->save_timestamp($stamp1, "parser");
+}
 
 /**
  * Language was set earlier, but we can over-ride it in the session.