]> git.mxchange.org Git - friendica.git/blobdiff - src/Core/Worker.php
Merge pull request #11506 from annando/featured-worker
[friendica.git] / src / Core / Worker.php
index fb3470270e2a08d36fd27e2495bdccf80717cb70..e29cf765a4fa38c5885798ef396cc0c6a9b8f89a 100644 (file)
@@ -1,6 +1,6 @@
 <?php
 /**
- * @copyright Copyright (C) 2020, Friendica
+ * @copyright Copyright (C) 2010-2022, the Friendica project
  *
  * @license GNU AGPL version 3 or any later version
  *
@@ -21,7 +21,8 @@
 
 namespace Friendica\Core;
 
-use Friendica\Core;
+use Friendica\App\Mode;
+use Friendica\Core\Worker\Entity\Process;
 use Friendica\Database\DBA;
 use Friendica\DI;
 use Friendica\Util\DateTimeFormat;
@@ -49,29 +50,30 @@ class Worker
        private static $lock_duration = 0;
        private static $last_update;
        private static $state;
+       private static $daemon_mode = null;
+       /** @var Process */
+       private static $process;
 
        /**
         * Processes the tasks that are in the workerqueue table
         *
         * @param boolean $run_cron Should the cron processes be executed?
+        * @param Process $process  The current running process
         * @return void
         * @throws \Friendica\Network\HTTPException\InternalServerErrorException
         */
-       public static function processQueue($run_cron = true)
+       public static function processQueue($run_cron, Process $process)
        {
-               // Ensure that all "strtotime" operations do run timezone independent
-               date_default_timezone_set('UTC');
-
                self::$up_start = microtime(true);
 
                // At first check the maximum load. We shouldn't continue with a high load
-               if (DI::process()->isMaxLoadReached()) {
+               if (DI::system()->isMaxLoadReached()) {
                        Logger::notice('Pre check: maximum load reached, quitting.');
                        return;
                }
 
                // We now start the process. This is done after the load check since this could increase the load.
-               DI::process()->start();
+               self::$process = $process;
 
                // Kill stale processes every 5 minutes
                $last_cleanup = DI::config()->get('system', 'worker_last_cleaned', 0);
@@ -95,15 +97,18 @@ class Worker
 
                // We fetch the next queue entry that is about to be executed
                while ($r = self::workerProcess()) {
+                       if (self::IPCJobsExists(getmypid())) {
+                               self::IPCDeleteJobState(getmypid());
+                       }
+
                        // Don't refetch when a worker fetches tasks for multiple workers
                        $refetched = DI::config()->get('system', 'worker_multiple_fetch');
                        foreach ($r as $entry) {
-                               // Assure that the priority is an integer value
-                               $entry['priority'] = (int)$entry['priority'];
+                               $entry = self::checkPriority($entry);
 
                                // The work will be done
                                if (!self::execute($entry)) {
-                                       Logger::info('Process execution failed, quitting.');
+                                       Logger::notice('Process execution failed, quitting.');
                                        return;
                                }
 
@@ -125,14 +130,14 @@ class Worker
                                if (DI::lock()->acquire(self::LOCK_WORKER, 0)) {
                                // Count active workers and compare them with a maximum value that depends on the load
                                        if (self::tooMuchWorkers()) {
-                                               Logger::info('Active worker limit reached, quitting.');
+                                               Logger::notice('Active worker limit reached, quitting.');
                                                DI::lock()->release(self::LOCK_WORKER);
                                                return;
                                        }
 
                                        // Check free memory
-                                       if (DI::process()->isMinMemoryReached()) {
-                                               Logger::notice('Memory limit reached, quitting.');
+                                       if (DI::system()->isMinMemoryReached()) {
+                                               Logger::warning('Memory limit reached, quitting.');
                                                DI::lock()->release(self::LOCK_WORKER);
                                                return;
                                        }
@@ -144,19 +149,41 @@ class Worker
                        // Quit the worker once every cron interval
                        if (time() > ($starttime + (DI::config()->get('system', 'cron_interval') * 60))) {
                                Logger::info('Process lifetime reached, respawning.');
-                               self::unclaimProcess();
-                               self::spawnWorker();
+                               self::unclaimProcess($process);
+                               if (self::isDaemonMode()) {
+                                       self::IPCSetJobState(true);
+                               } else {
+                                       self::spawnWorker();
+                               }
                                return;
                        }
                }
 
                // Cleaning up. Possibly not needed, but it doesn't harm anything.
-               if (DI::config()->get('system', 'worker_daemon_mode', false)) {
+               if (self::isDaemonMode()) {
                        self::IPCSetJobState(false);
                }
                Logger::info("Couldn't select a workerqueue entry, quitting process", ['pid' => getmypid()]);
        }
 
+       /**
+        * Check and fix the priority of a worker task
+        * @param array $entry
+        * @return array
+        */
+       private static function checkPriority(array $entry)
+       {
+               $entry['priority'] = (int)$entry['priority'];
+
+               if (!in_array($entry['priority'], PRIORITIES)) {
+                       Logger::warning('Invalid priority', ['entry' => $entry, 'callstack' => System::callstack(20)]);
+                       DBA::update('workerqueue', ['priority' => PRIORITY_MEDIUM], ['id' => $entry['id']]);
+                       $entry['priority'] = PRIORITY_MEDIUM;
+               }
+
+               return $entry;
+       }
+
        /**
         * Checks if the system is ready.
         *
@@ -168,28 +195,28 @@ class Worker
        {
                // Count active workers and compare them with a maximum value that depends on the load
                if (self::tooMuchWorkers()) {
-                       Logger::info('Active worker limit reached, quitting.');
+                       Logger::notice('Active worker limit reached, quitting.');
                        return false;
                }
 
                // Do we have too few memory?
-               if (DI::process()->isMinMemoryReached()) {
-                       Logger::notice('Memory limit reached, quitting.');
+               if (DI::system()->isMinMemoryReached()) {
+                       Logger::warning('Memory limit reached, quitting.');
                        return false;
                }
 
                // Possibly there are too much database connections
                if (self::maxConnectionsReached()) {
-                       Logger::notice('Maximum connections reached, quitting.');
+                       Logger::warning('Maximum connections reached, quitting.');
                        return false;
                }
 
                // Possibly there are too much database processes that block the system
-               if (DI::process()->isMaxProcessesReached()) {
-                       Logger::notice('Maximum processes reached, quitting.');
+               if (DI::system()->isMaxProcessesReached()) {
+                       Logger::warning('Maximum processes reached, quitting.');
                        return false;
                }
-               
+
                return true;
        }
 
@@ -250,7 +277,7 @@ class Worker
                $workerqueue = DBA::selectFirst('workerqueue', ['priority'], $condition, ['order' => ['priority']]);
                self::$db_duration += (microtime(true) - $stamp);
                if (DBA::isResult($workerqueue)) {
-                       return $workerqueue["priority"];
+                       return $workerqueue['priority'];
                } else {
                        return 0;
                }
@@ -270,6 +297,44 @@ class Worker
                return DBA::exists('workerqueue', $condition);
        }
 
+       /**
+        * Checks if the given file is valid to be included
+        *
+        * @param mixed $file
+        * @return bool
+        */
+       private static function validateInclude(&$file)
+       {
+               $orig_file = $file;
+
+               $file = realpath($file);
+
+               if (strpos($file, getcwd()) !== 0) {
+                       return false;
+               }
+
+               $file = str_replace(getcwd() . "/", "", $file, $count);
+               if ($count != 1) {
+                       return false;
+               }
+
+               if ($orig_file !== $file) {
+                       return false;
+               }
+
+               $valid = false;
+               if (strpos($file, "include/") === 0) {
+                       $valid = true;
+               }
+
+               if (strpos($file, "addon/") === 0) {
+                       $valid = true;
+               }
+
+               // Simply return flag
+               return $valid;
+       }
+
        /**
         * Execute a worker entry
         *
@@ -289,18 +354,22 @@ class Worker
                }
 
                // Constantly check the number of parallel database processes
-               if (DI::process()->isMaxProcessesReached()) {
-                       Logger::notice("Max processes reached for process", ['pid' => $mypid]);
+               if (DI::system()->isMaxProcessesReached()) {
+                       Logger::warning("Max processes reached for process", ['pid' => $mypid]);
                        return false;
                }
 
                // Constantly check the number of available database connections to let the frontend be accessible at any time
                if (self::maxConnectionsReached()) {
-                       Logger::notice("Max connection reached for process", ['pid' => $mypid]);
+                       Logger::warning("Max connection reached for process", ['pid' => $mypid]);
                        return false;
                }
 
                $argv = json_decode($queue['parameter'], true);
+               if (!is_array($argv)) {
+                       $argv = [];
+               }
+
                if (!empty($queue['command'])) {
                        array_unshift($argv, $queue['command']);
                }
@@ -349,7 +418,7 @@ class Worker
                        $include = "include/".$include.".php";
                }
 
-               if (!validate_include($include)) {
+               if (!self::validateInclude($include)) {
                        Logger::warning("Include file is not valid", ['file' => $argv[0]]);
                        $stamp = (float)microtime(true);
                        DBA::delete('workerqueue', ['id' => $queue["id"]]);
@@ -411,9 +480,15 @@ class Worker
        {
                $a = DI::app();
 
+               $cooldown = DI::config()->get("system", "worker_cooldown", 0);
+               if ($cooldown > 0) {
+                       Logger::info('Pre execution cooldown.', ['priority' => $queue['priority'], 'id' => $queue["id"], 'cooldown' => $cooldown]);
+                       sleep($cooldown);
+               }
+
                Logger::enableWorker($funcname);
 
-               Logger::info("Process start.", ['priority' => $queue["priority"], 'id' => $queue["id"]]);
+               Logger::info("Process start.", ['priority' => $queue['priority'], 'id' => $queue["id"]]);
 
                $stamp = (float)microtime(true);
 
@@ -421,12 +496,7 @@ class Worker
                // For this reason the variables have to be initialized.
                DI::profiler()->reset();
 
-               if (!in_array($queue['priority'], PRIORITIES)) {
-                       Logger::warning('Invalid priority', ['queue' => $queue, 'callstack' => System::callstack(20)]);
-                       $queue['priority'] = PRIORITY_MEDIUM;
-               }
-
-               $a->queue = $queue;
+               $a->setQueue($queue);
 
                $up_duration = microtime(true) - self::$up_start;
 
@@ -442,7 +512,7 @@ class Worker
 
                Logger::disableWorker();
 
-               unset($a->queue);
+               $a->setQueue([]);
 
                $duration = (microtime(true) - $stamp);
 
@@ -470,23 +540,21 @@ class Worker
                self::$lock_duration = 0;
 
                if ($duration > 3600) {
-                       Logger::info('Longer than 1 hour.', ['priority' => $queue["priority"], 'id' => $queue["id"], 'duration' => round($duration/60, 3)]);
+                       Logger::info('Longer than 1 hour.', ['priority' => $queue['priority'], 'id' => $queue["id"], 'duration' => round($duration/60, 3)]);
                } elseif ($duration > 600) {
-                       Logger::info('Longer than 10 minutes.', ['priority' => $queue["priority"], 'id' => $queue["id"], 'duration' => round($duration/60, 3)]);
+                       Logger::info('Longer than 10 minutes.', ['priority' => $queue['priority'], 'id' => $queue["id"], 'duration' => round($duration/60, 3)]);
                } elseif ($duration > 300) {
-                       Logger::info('Longer than 5 minutes.', ['priority' => $queue["priority"], 'id' => $queue["id"], 'duration' => round($duration/60, 3)]);
+                       Logger::info('Longer than 5 minutes.', ['priority' => $queue['priority'], 'id' => $queue["id"], 'duration' => round($duration/60, 3)]);
                } elseif ($duration > 120) {
-                       Logger::info('Longer than 2 minutes.', ['priority' => $queue["priority"], 'id' => $queue["id"], 'duration' => round($duration/60, 3)]);
+                       Logger::info('Longer than 2 minutes.', ['priority' => $queue['priority'], 'id' => $queue["id"], 'duration' => round($duration/60, 3)]);
                }
 
-               Logger::info('Process done.', ['priority' => $queue["priority"], 'id' => $queue["id"], 'duration' => round($duration, 3)]);
+               Logger::info('Process done.', ['priority' => $queue['priority'], 'id' => $queue["id"], 'duration' => round($duration, 3)]);
 
                DI::profiler()->saveLog(DI::logger(), "ID " . $queue["id"] . ": " . $funcname);
 
-               $cooldown = DI::config()->get("system", "worker_cooldown", 0);
-
                if ($cooldown > 0) {
-                       Logger::info('Cooldown.', ['priority' => $queue["priority"], 'id' => $queue["id"], 'cooldown' => $cooldown]);
+                       Logger::info('Post execution cooldown.', ['priority' => $queue['priority'], 'id' => $queue["id"], 'cooldown' => $cooldown]);
                        sleep($cooldown);
                }
        }
@@ -540,7 +608,7 @@ class Worker
                        $level = ($used / $max) * 100;
 
                        if ($level >= $maxlevel) {
-                               Logger::notice("Maximum level (".$maxlevel."%) of user connections reached: ".$used."/".$max);
+                               Logger::warning("Maximum level (".$maxlevel."%) of user connections reached: ".$used."/".$max);
                                return true;
                        }
                }
@@ -570,7 +638,7 @@ class Worker
                if ($level < $maxlevel) {
                        return false;
                }
-               Logger::notice("Maximum level (".$level."%) of system connections reached: ".$used."/".$max);
+               Logger::warning("Maximum level (".$level."%) of system connections reached: ".$used."/".$max);
                return true;
        }
 
@@ -592,6 +660,8 @@ class Worker
                self::$db_duration += (microtime(true) - $stamp);
 
                while ($entry = DBA::fetch($entries)) {
+                       $entry = self::checkPriority($entry);
+
                        if (!posix_kill($entry["pid"], 0)) {
                                $stamp = (float)microtime(true);
                                DBA::update(
@@ -603,14 +673,10 @@ class Worker
                                self::$db_duration_write += (microtime(true) - $stamp);
                        } else {
                                // Kill long running processes
-                               // Check if the priority is in a valid range
-                               if (!in_array($entry["priority"], [PRIORITY_CRITICAL, PRIORITY_HIGH, PRIORITY_MEDIUM, PRIORITY_LOW, PRIORITY_NEGLIGIBLE])) {
-                                       $entry["priority"] = PRIORITY_MEDIUM;
-                               }
 
                                // Define the maximum durations
                                $max_duration_defaults = [PRIORITY_CRITICAL => 720, PRIORITY_HIGH => 10, PRIORITY_MEDIUM => 60, PRIORITY_LOW => 180, PRIORITY_NEGLIGIBLE => 720];
-                               $max_duration = $max_duration_defaults[$entry["priority"]];
+                               $max_duration = $max_duration_defaults[$entry['priority']];
 
                                $argv = json_decode($entry['parameter'], true);
                                if (!empty($entry['command'])) {
@@ -632,12 +698,12 @@ class Worker
                                        // We killed the stale process.
                                        // To avoid a blocking situation we reschedule the process at the beginning of the queue.
                                        // Additionally we are lowering the priority. (But not PRIORITY_CRITICAL)
-                                       $new_priority = $entry["priority"];
-                                       if ($entry["priority"] == PRIORITY_HIGH) {
+                                       $new_priority = $entry['priority'];
+                                       if ($entry['priority'] == PRIORITY_HIGH) {
                                                $new_priority = PRIORITY_MEDIUM;
-                                       } elseif ($entry["priority"] == PRIORITY_MEDIUM) {
+                                       } elseif ($entry['priority'] == PRIORITY_MEDIUM) {
                                                $new_priority = PRIORITY_LOW;
-                                       } elseif ($entry["priority"] != PRIORITY_CRITICAL) {
+                                       } elseif ($entry['priority'] != PRIORITY_CRITICAL) {
                                                $new_priority = PRIORITY_NEGLIGIBLE;
                                        }
                                        $stamp = (float)microtime(true);
@@ -697,13 +763,10 @@ class Worker
                                        }
 
                                        $stamp = (float)microtime(true);
-                                       $jobs = DBA::p("SELECT COUNT(*) AS `jobs` FROM `workerqueue` WHERE `done` AND `executed` > UTC_TIMESTAMP() - INTERVAL ? MINUTE", $interval);
+                                       $jobs = DBA::count('workerqueue', ["`done` AND `executed` > ?", DateTimeFormat::utc('now - ' . $interval . ' minute')]);
                                        self::$db_duration += (microtime(true) - $stamp);
                                        self::$db_duration_stat += (microtime(true) - $stamp);
-                                       if ($job = DBA::fetch($jobs)) {
-                                               $jobs_per_minute[$interval] = number_format($job['jobs'] / $interval, 0);
-                                       }
-                                       DBA::close($jobs);
+                                       $jobs_per_minute[$interval] = number_format($jobs / $interval, 0);
                                }
                                $processlist = ' - jpm: '.implode('/', $jobs_per_minute);
                        }
@@ -724,15 +787,12 @@ class Worker
                                self::$db_duration_stat += (microtime(true) - $stamp);
                                while ($entry = DBA::fetch($jobs)) {
                                        $stamp = (float)microtime(true);
-                                       $processes = DBA::p("SELECT COUNT(*) AS `running` FROM `workerqueue-view` WHERE `priority` = ?", $entry["priority"]);
+                                       $running = DBA::count('workerqueue-view', ['priority' => $entry['priority']]);
                                        self::$db_duration += (microtime(true) - $stamp);
                                        self::$db_duration_stat += (microtime(true) - $stamp);
-                                       if ($process = DBA::fetch($processes)) {
-                                               $idle_workers -= $process["running"];
-                                               $waiting_processes += $entry["entries"];
-                                               $listitem[$entry["priority"]] = $entry["priority"].":".$process["running"]."/".$entry["entries"];
-                                       }
-                                       DBA::close($processes);
+                                       $idle_workers -= $running;
+                                       $waiting_processes += $entry["entries"];
+                                       $listitem[$entry['priority']] = $entry['priority'] . ":" . $running . "/" . $entry["entries"];
                                }
                                DBA::close($jobs);
                        } else {
@@ -744,7 +804,7 @@ class Worker
 
                                while ($entry = DBA::fetch($jobs)) {
                                        $idle_workers -= $entry["running"];
-                                       $listitem[$entry["priority"]] = $entry["priority"].":".$entry["running"];
+                                       $listitem[$entry['priority']] = $entry['priority'].":".$entry["running"];
                                }
                                DBA::close($jobs);
                        }
@@ -770,7 +830,7 @@ class Worker
                        // Are there fewer workers running as possible? Then fork a new one.
                        if (!DI::config()->get("system", "worker_dont_fork", false) && ($queues > ($active + 1)) && self::entriesExists()) {
                                Logger::info("There are fewer workers as possible, fork a new worker.", ['active' => $active, 'queues' => $queues]);
-                               if (DI::config()->get('system', 'worker_daemon_mode', false)) {
+                               if (self::isDaemonMode()) {
                                        self::IPCSetJobState(true);
                                } else {
                                        self::spawnWorker();
@@ -779,7 +839,7 @@ class Worker
                }
 
                // if there are too much worker, we don't spawn a new one.
-               if (DI::config()->get('system', 'worker_daemon_mode', false) && ($active > $queues)) {
+               if (self::isDaemonMode() && ($active > $queues)) {
                        self::IPCSetJobState(false);
                }
 
@@ -795,7 +855,7 @@ class Worker
        private static function activeWorkers()
        {
                $stamp = (float)microtime(true);
-               $count = DBA::count('process', ['command' => 'Worker.php']);
+               $count = DI::process()->countCommand('Worker.php');
                self::$db_duration += (microtime(true) - $stamp);
                self::$db_duration_count += (microtime(true) - $stamp);
                return $count;
@@ -813,7 +873,7 @@ class Worker
                $stamp = (float)microtime(true);
 
                $queues = DBA::p("SELECT `process`.`pid`, COUNT(`workerqueue`.`pid`) AS `entries` FROM `process`
-                       LEFT JOIN `workerqueue` ON `workerqueue`.`pid` = `process`.`pid` AND NOT `workerqueue`.`done` 
+                       LEFT JOIN `workerqueue` ON `workerqueue`.`pid` = `process`.`pid` AND NOT `workerqueue`.`done`
                        GROUP BY `process`.`pid`");
                while ($queue = DBA::fetch($queues)) {
                        $ids[$queue['pid']] = $queue['entries'];
@@ -1058,126 +1118,123 @@ class Worker
        /**
         * Removes a workerqueue entry from the current process
         *
+        * @param Process $process the process behind the workerqueue
+        *
         * @return void
         * @throws \Exception
         */
-       public static function unclaimProcess()
+       public static function unclaimProcess(Process $process)
        {
-               $mypid = getmypid();
-
                $stamp = (float)microtime(true);
-               DBA::update('workerqueue', ['executed' => DBA::NULL_DATETIME, 'pid' => 0], ['pid' => $mypid, 'done' => false]);
+               DBA::update('workerqueue', ['executed' => DBA::NULL_DATETIME, 'pid' => 0], ['pid' => $process->pid, 'done' => false]);
                self::$db_duration += (microtime(true) - $stamp);
                self::$db_duration_write += (microtime(true) - $stamp);
        }
 
        /**
-        * Call the front end worker
+        * Runs the cron processes
         *
         * @return void
         * @throws \Friendica\Network\HTTPException\InternalServerErrorException
         */
-       public static function callWorker()
+       private static function runCron()
        {
-               if (!DI::config()->get("system", "frontend_worker")) {
-                       return;
-               }
+               Logger::info('Add cron entries');
 
-               $url = DI::baseUrl() . '/worker';
-               DI::httpRequest()->fetch($url, 1);
+               // Check for spooled items
+               self::add(['priority' => PRIORITY_HIGH, 'force_priority' => true], 'SpoolPost');
+
+               // Run the cron job that calls all other jobs
+               self::add(['priority' => PRIORITY_MEDIUM, 'force_priority' => true], 'Cron');
+
+               // Cleaning dead processes
+               self::killStaleWorkers();
+
+               // Remove old entries from the workerqueue
+               self::cleanWorkerQueue();
        }
 
        /**
-        * Call the front end worker if there aren't any active
+        * Remove old entries from the workerqueue
         *
         * @return void
-        * @throws \Friendica\Network\HTTPException\InternalServerErrorException
         */
-       public static function executeIfIdle()
+       private static function cleanWorkerQueue()
        {
-               self::checkDaemonState();
+               DBA::delete('workerqueue', ["`done` AND `executed` < ?", DateTimeFormat::utc('now - 1 hour')]);
+
+               // Optimizing this table only last seconds
+               if (DI::config()->get('system', 'optimize_tables')) {
+                       // We are acquiring the two locks from the worker to avoid locking problems
+                       if (DI::lock()->acquire(Worker::LOCK_PROCESS, 10)) {
+                               if (DI::lock()->acquire(Worker::LOCK_WORKER, 10)) {
+                                       DBA::e("OPTIMIZE TABLE `workerqueue`");
+                                       DBA::e("OPTIMIZE TABLE `process`");
+                                       DI::lock()->release(Worker::LOCK_WORKER);
+                               }
+                               DI::lock()->release(Worker::LOCK_PROCESS);
+                       }
+               }
+       }
 
-               if (!DI::config()->get("system", "frontend_worker")) {
+       /**
+        * Fork a child process
+        *
+        * @param boolean $do_cron
+        * @return void
+        */
+       private static function forkProcess(bool $do_cron)
+       {
+               if (DI::system()->isMinMemoryReached()) {
+                       Logger::warning('Memory limit reached - quitting');
                        return;
                }
 
-               // Do we have "proc_open"? Then we can fork the worker
-               if (function_exists("proc_open")) {
-                       // When was the last time that we called the worker?
-                       // Less than one minute? Then we quit
-                       if ((time() - DI::config()->get("system", "worker_started")) < 60) {
-                               return;
-                       }
-
-                       DI::config()->set("system", "worker_started", time());
+               // Children inherit their parent's database connection.
+               // To avoid problems we disconnect and connect both parent and child
+               DBA::disconnect();
+               $pid = pcntl_fork();
+               if ($pid == -1) {
+                       DBA::connect();
+                       Logger::warning('Could not spawn worker');
+                       return;
+               } elseif ($pid) {
+                       // The parent process continues here
+                       DBA::connect();
 
-                       // Do we have enough running workers? Then we quit here.
-                       if (self::tooMuchWorkers()) {
-                               // Cleaning dead processes
-                               self::killStaleWorkers();
-                               DI::modelProcess()->deleteInactive();
+                       self::IPCSetJobState(true, $pid);
+                       Logger::info('Spawned new worker', ['pid' => $pid]);
 
-                               return;
+                       $cycles = 0;
+                       while (self::IPCJobsExists($pid) && (++$cycles < 100)) {
+                               usleep(10000);
                        }
 
-                       self::runCron();
-
-                       Logger::info('Call worker');
-                       self::spawnWorker();
+                       Logger::info('Spawned worker is ready', ['pid' => $pid, 'wait_cycles' => $cycles]);
                        return;
                }
 
-               // We cannot execute background processes.
-               // We now run the processes from the frontend.
-               // This won't work with long running processes.
-               self::runCron();
-
-               self::clearProcesses();
+               // We now are in the new worker
+               DBA::connect();
 
-               $workers = self::activeWorkers();
+               DI::flushLogger();
+               $process = DI::process()->create(getmypid(), basename(__FILE__));
 
-               if ($workers == 0) {
-                       self::callWorker();
+               $cycles = 0;
+               while (!self::IPCJobsExists($process->pid) && (++$cycles < 100)) {
+                       usleep(10000);
                }
-       }
 
-       /**
-        * Removes long running worker processes
-        *
-        * @return void
-        * @throws \Friendica\Network\HTTPException\InternalServerErrorException
-        */
-       public static function clearProcesses()
-       {
-               $timeout = DI::config()->get("system", "frontend_worker_timeout", 10);
+               Logger::info('Worker spawned', ['pid' => $process->pid, 'wait_cycles' => $cycles]);
 
-               /// @todo We should clean up the corresponding workerqueue entries as well
-               $stamp = (float)microtime(true);
-               $condition = ["`created` < ? AND `command` = 'worker.php'",
-                               DateTimeFormat::utc("now - ".$timeout." minutes")];
-               DBA::delete('process', $condition);
-               self::$db_duration = (microtime(true) - $stamp);
-               self::$db_duration_write += (microtime(true) - $stamp);
-       }
+               self::processQueue($do_cron, $process);
 
-       /**
-        * Runs the cron processes
-        *
-        * @return void
-        * @throws \Friendica\Network\HTTPException\InternalServerErrorException
-        */
-       private static function runCron()
-       {
-               Logger::info('Add cron entries');
+               self::unclaimProcess($process);
 
-               // Check for spooled items
-               self::add(['priority' => PRIORITY_HIGH, 'force_priority' => true], 'SpoolPost');
-
-               // Run the cron job that calls all other jobs
-               self::add(['priority' => PRIORITY_MEDIUM, 'force_priority' => true], 'Cron');
-
-               // Cleaning dead processes
-               self::killStaleWorkers();
+               self::IPCSetJobState(false, $process->pid);
+               DI::process()->delete($process);
+               Logger::info('Worker ended', ['pid' => $process->pid]);
+               exit();
        }
 
        /**
@@ -1189,16 +1246,12 @@ class Worker
         */
        public static function spawnWorker($do_cron = false)
        {
-               $command = 'bin/worker.php';
-
-               $args = ['no_cron' => !$do_cron];
-
-               $a = DI::app();
-               $process = new Core\Process(DI::logger(), DI::mode(), DI::config(), DI::modelProcess(), $a->getBasePath(), getmypid());
-               $process->run($command, $args);
-
-               // after spawning we have to remove the flag.
-               if (DI::config()->get('system', 'worker_daemon_mode', false)) {
+               if (self::isDaemonMode() && DI::config()->get('system', 'worker_fork')) {
+                       self::forkProcess($do_cron);
+               } else {
+                       DI::system()->run('bin/worker.php', ['no_cron' => !$do_cron]);
+               }
+               if (self::isDaemonMode()) {
                        self::IPCSetJobState(false);
                }
        }
@@ -1212,7 +1265,7 @@ class Worker
         * or: Worker::add(PRIORITY_HIGH, "Notifier", Delivery::DELETION, $drop_id);
         * or: Worker::add(array('priority' => PRIORITY_HIGH, 'dont_fork' => true), "Delivery", $post_id);
         *
-        * @return boolean "false" if worker queue entry already existed or there had been an error
+        * @return int "0" if worker queue entry already existed or there had been an error, otherwise the ID of the worker task
         * @throws \Friendica\Network\HTTPException\InternalServerErrorException
         * @note $cmd and string args are surrounded with ""
         *
@@ -1220,19 +1273,17 @@ class Worker
         *    array $arr
         *
         */
-       public static function add($cmd)
+       public static function add(...$args)
        {
-               $args = func_get_args();
-
                if (!count($args)) {
-                       return false;
+                       return 0;
                }
 
                $arr = ['args' => $args, 'run_cmd' => true];
 
                Hook::callAll("proc_run", $arr);
                if (!$arr['run_cmd'] || !count($args)) {
-                       return true;
+                       return 1;
                }
 
                $priority = PRIORITY_MEDIUM;
@@ -1262,35 +1313,37 @@ class Worker
                        if (isset($run_parameter['force_priority'])) {
                                $force_priority = $run_parameter['force_priority'];
                        }
+               } else {
+                       throw new \InvalidArgumentException('Priority number or task parameter array expected as first argument');
                }
 
                $command = array_shift($args);
                $parameters = json_encode($args);
                $found = DBA::exists('workerqueue', ['command' => $command, 'parameter' => $parameters, 'done' => false]);
-               $added = false;
+               $added = 0;
 
-               if (!in_array($priority, PRIORITIES)) {
+               if (!is_int($priority) || !in_array($priority, PRIORITIES)) {
                        Logger::warning('Invalid priority', ['priority' => $priority, 'command' => $command, 'callstack' => System::callstack(20)]);
                        $priority = PRIORITY_MEDIUM;
                }
 
                // Quit if there was a database error - a precaution for the update process to 3.5.3
                if (DBA::errorNo() != 0) {
-                       return false;
+                       return 0;
                }
 
                if (!$found) {
-                       $added = DBA::insert('workerqueue', ['command' => $command, 'parameter' => $parameters, 'created' => $created,
-                               'priority' => $priority, 'next_try' => $delayed]);
-                       if (!$added) {
-                               return false;
+                       if (!DBA::insert('workerqueue', ['command' => $command, 'parameter' => $parameters, 'created' => $created,
+                               'priority' => $priority, 'next_try' => $delayed])) {
+                               return 0;
                        }
+                       $added = DBA::lastInsertId();
                } elseif ($force_priority) {
                        DBA::update('workerqueue', ['priority' => $priority], ['command' => $command, 'parameter' => $parameters, 'done' => false, 'pid' => 0]);
                }
 
                // Set the IPC flag to ensure an immediate process execution via daemon
-               if (DI::config()->get('system', 'worker_daemon_mode', false)) {
+               if (self::isDaemonMode()) {
                        self::IPCSetJobState(true);
                }
 
@@ -1315,7 +1368,7 @@ class Worker
                }
 
                // Quit on daemon mode
-               if (DI::config()->get('system', 'worker_daemon_mode', false)) {
+               if (self::isDaemonMode()) {
                        return $added;
                }
 
@@ -1352,7 +1405,7 @@ class Worker
                                $new_retrial = $retrial;
                        }
                }
-               Logger::info('New retrial for task', ['id' => $queue['id'], 'created' => $queue['created'], 'old' => $queue['retrial'], 'new' => $new_retrial]);
+               Logger::notice('New retrial for task', ['id' => $queue['id'], 'created' => $queue['created'], 'old' => $queue['retrial'], 'new' => $new_retrial]);
                return $new_retrial;
        }
 
@@ -1360,16 +1413,18 @@ class Worker
         * Defers the current worker entry
         *
         * @return boolean had the entry been deferred?
+        * @throws \Exception
         */
-       public static function defer()
+       public static function defer(): bool
        {
-               if (empty(DI::app()->queue)) {
+               $queue = DI::app()->getQueue();
+
+               if (empty($queue)) {
                        return false;
                }
 
-               $queue = DI::app()->queue;
+               $queue = self::checkPriority($queue);
 
-               $retrial = $queue['retrial'];
                $id = $queue['id'];
                $priority = $queue['priority'];
 
@@ -1378,7 +1433,7 @@ class Worker
                $new_retrial = self::getNextRetrial($queue, $max_level);
 
                if ($new_retrial > $max_level) {
-                       Logger::info('The task exceeded the maximum retry count', ['id' => $id, 'created' => $queue['created'], 'old_prio' => $queue['priority'], 'old_retrial' => $queue['retrial'], 'max_level' => $max_level, 'retrial' => $new_retrial]);
+                       Logger::notice('The task exceeded the maximum retry count', ['id' => $id, 'created' => $queue['created'], 'old_prio' => $queue['priority'], 'old_retrial' => $queue['retrial'], 'max_level' => $max_level, 'retrial' => $new_retrial]);
                        return false;
                }
 
@@ -1409,12 +1464,27 @@ class Worker
         * Set the flag if some job is waiting
         *
         * @param boolean $jobs Is there a waiting job?
+        * @param int $key Key number
+        * @throws \Exception
+        */
+       public static function IPCSetJobState(bool $jobs, int $key = 0)
+       {
+               $stamp = (float)microtime(true);
+               DBA::replace('worker-ipc', ['jobs' => $jobs, 'key' => $key]);
+               self::$db_duration += (microtime(true) - $stamp);
+               self::$db_duration_write += (microtime(true) - $stamp);
+       }
+
+       /**
+        * Delete a key entry
+        *
+        * @param int $key Key number
         * @throws \Exception
         */
-       public static function IPCSetJobState($jobs)
+       public static function IPCDeleteJobState(int $key)
        {
                $stamp = (float)microtime(true);
-               DBA::update('worker-ipc', ['jobs' => $jobs], ['key' => 1], true);
+               DBA::delete('worker-ipc', ['key' => $key]);
                self::$db_duration += (microtime(true) - $stamp);
                self::$db_duration_write += (microtime(true) - $stamp);
        }
@@ -1422,13 +1492,14 @@ class Worker
        /**
         * Checks if some worker job waits to be executed
         *
+        * @param int $key Key number
         * @return bool
         * @throws \Exception
         */
-       public static function IPCJobsExists()
+       public static function IPCJobsExists(int $key = 0)
        {
                $stamp = (float)microtime(true);
-               $row = DBA::selectFirst('worker-ipc', ['jobs'], ['key' => 1]);
+               $row = DBA::selectFirst('worker-ipc', ['jobs'], ['key' => $key]);
                self::$db_duration += (microtime(true) - $stamp);
 
                // When we don't have a row, no job is running
@@ -1439,6 +1510,51 @@ class Worker
                return (bool)$row['jobs'];
        }
 
+       /**
+        * Checks if the worker is running in the daemon mode.
+        *
+        * @return boolean
+        */
+       public static function isDaemonMode()
+       {
+               if (!is_null(self::$daemon_mode)) {
+                       return self::$daemon_mode;
+               }
+
+               if (DI::mode()->getExecutor() == Mode::DAEMON) {
+                       return true;
+               }
+
+               $daemon_mode = DI::config()->get('system', 'worker_daemon_mode', false, true);
+               if ($daemon_mode) {
+                       return $daemon_mode;
+               }
+
+               if (!function_exists('pcntl_fork')) {
+                       self::$daemon_mode = false;
+                       return false;
+               }
+
+               $pidfile = DI::config()->get('system', 'pidfile');
+               if (empty($pidfile)) {
+                       // No pid file, no daemon
+                       self::$daemon_mode = false;
+                       return false;
+               }
+
+               if (!is_readable($pidfile)) {
+                       // No pid file. We assume that the daemon had been intentionally stopped.
+                       self::$daemon_mode = false;
+                       return false;
+               }
+
+               $pid = intval(file_get_contents($pidfile));
+               $running = posix_kill($pid, 0);
+
+               self::$daemon_mode = $running;
+               return $running;
+       }
+
        /**
         * Test if the daemon is running. If not, it will be started
         *
@@ -1490,12 +1606,11 @@ class Worker
         */
        private static function spawnDaemon()
        {
-               Logger::info('Starting new daemon process');
+               Logger::notice('Starting new daemon process');
                $command = 'bin/daemon.php';
                $a = DI::app();
-               $process = new Core\Process(DI::logger(), DI::mode(), DI::config(), DI::modelProcess(), $a->getBasePath(), getmypid());
-               $process->run($command, ['start']);
-               Logger::info('New daemon process started');
+               DI::system()->run($command, ['start']);
+               Logger::notice('New daemon process started');
        }
 
        /**
@@ -1538,7 +1653,7 @@ class Worker
                } else {
                        Logger::info('We are outside the maintenance window', ['current' => date('H:i:s', $current), 'start' => date('H:i:s', $start), 'end' => date('H:i:s', $end)]);
                }
-               
+
                return $execute;
        }
 }