X-Git-Url: https://git.mxchange.org/?a=blobdiff_plain;f=src%2FCore%2FWorker.php;h=96f3e7ae042e30fae459cff6ca272d6f1bdba261;hb=4930737cc448bcff196a2e06065249c0ffc363d0;hp=3443e6608e98248e4177f4fe3ffa4900963e910e;hpb=f7b6507438a551975016076784ef90079d1662fa;p=friendica.git

diff --git a/src/Core/Worker.php b/src/Core/Worker.php
index 3443e6608e..96f3e7ae04 100644
--- a/src/Core/Worker.php
+++ b/src/Core/Worker.php
@@ -21,8 +21,6 @@
 
 namespace Friendica\Core;
 
-use Friendica\App\Mode;
-use Friendica\Core;
 use Friendica\Core\Worker\Entity\Process;
 use Friendica\Database\DBA;
 use Friendica\DI;
@@ -33,6 +31,21 @@ use Friendica\Util\DateTimeFormat;
  */
 class Worker
 {
+	/**
+	 * @name Priority
+	 *
+	 * Process priority for the worker
+	 * @{
+	 */
+	const PRIORITY_UNDEFINED  = 0;
+	const PRIORITY_CRITICAL   = 10;
+	const PRIORITY_HIGH       = 20;
+	const PRIORITY_MEDIUM     = 30;
+	const PRIORITY_LOW        = 40;
+	const PRIORITY_NEGLIGIBLE = 50;
+	const PRIORITIES          = [self::PRIORITY_CRITICAL, self::PRIORITY_HIGH, self::PRIORITY_MEDIUM, self::PRIORITY_LOW, self::PRIORITY_NEGLIGIBLE];
+	/* @}*/
+
 	const STATE_STARTUP    = 1; // Worker is in startup. This takes most time.
 	const STATE_LONG_LOOP  = 2; // Worker is processing the whole - long - loop.
 	const STATE_REFETCH    = 3; // Worker had refetched jobs in the execution loop.
@@ -51,7 +64,6 @@ class Worker
 	private static $lock_duration = 0;
 	private static $last_update;
 	private static $state;
-	private static $daemon_mode = null;
 	/** @var Process */
 	private static $process;
 
@@ -63,7 +75,7 @@ class Worker
 	 * @return void
 	 * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 	 */
-	public static function processQueue($run_cron, Process $process)
+	public static function processQueue(bool $run_cron, Process $process)
 	{
 		self::$up_start = microtime(true);
 
@@ -80,7 +92,7 @@ class Worker
 		$last_cleanup = DI::config()->get('system', 'worker_last_cleaned', 0);
 		if (time() > ($last_cleanup + 300)) {
 			DI::config()->set('system', 'worker_last_cleaned', time());
-			self::killStaleWorkers();
+			Worker\Cron::killStaleWorkers();
 		}
 
 		// Check if the system is ready
@@ -90,7 +102,7 @@ class Worker
 
 		// Now we start additional cron processes if we should do so
 		if ($run_cron) {
-			self::runCron();
+			Worker\Cron::run();
 		}
 
 		$last_check = $starttime = time();
@@ -98,23 +110,16 @@ 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());
+			if (Worker\IPC::JobsExists(getmypid())) {
+				Worker\IPC::DeleteJobState(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'];
-				if (!in_array($entry['priority'], PRIORITIES)) {
-					Logger::warning('Invalid priority', ['entry' => $entry, 'callstack' => System::callstack(20)]);
-					$entry['priority'] = PRIORITY_MEDIUM;
-				}
-
 				// The work will be done
 				if (!self::execute($entry)) {
-					Logger::notice('Process execution failed, quitting.');
+					Logger::warning('Process execution failed, quitting.', ['entry' => $entry]);
 					return;
 				}
 
@@ -153,11 +158,11 @@ class Worker
 			}
 
 			// Quit the worker once every cron interval
-			if (time() > ($starttime + (DI::config()->get('system', 'cron_interval') * 60))) {
+			if (time() > ($starttime + (DI::config()->get('system', 'cron_interval') * 60)) && !self::systemLimitReached()) {
 				Logger::info('Process lifetime reached, respawning.');
 				self::unclaimProcess($process);
-				if (self::isDaemonMode()) {
-					self::IPCSetJobState(true);
+				if (Worker\Daemon::isMode()) {
+					Worker\IPC::SetJobState(true);
 				} else {
 					self::spawnWorker();
 				}
@@ -166,8 +171,8 @@ class Worker
 		}
 
 		// Cleaning up. Possibly not needed, but it doesn't harm anything.
-		if (self::isDaemonMode()) {
-			self::IPCSetJobState(false);
+		if (Worker\Daemon::isMode()) {
+			Worker\IPC::SetJobState(false);
 		}
 		Logger::info("Couldn't select a workerqueue entry, quitting process", ['pid' => getmypid()]);
 	}
@@ -179,7 +184,7 @@ class Worker
 	 *
 	 * @return boolean
 	 */
-	public static function isReady()
+	public static function isReady(): bool
 	{
 		// Count active workers and compare them with a maximum value that depends on the load
 		if (self::tooMuchWorkers()) {
@@ -214,7 +219,7 @@ class Worker
 	 * @return boolean Returns "true" if tasks are existing
 	 * @throws \Exception
 	 */
-	public static function entriesExists()
+	public static function entriesExists(): bool
 	{
 		$stamp = (float)microtime(true);
 		$exists = DBA::exists('workerqueue', ["NOT `done` AND `pid` = 0 AND `next_try` < ?", DateTimeFormat::utcNow()]);
@@ -228,7 +233,7 @@ class Worker
 	 * @return integer Number of deferred entries in the worker queue
 	 * @throws \Exception
 	 */
-	private static function deferredEntries()
+	private static function deferredEntries(): int
 	{
 		$stamp = (float)microtime(true);
 		$count = DBA::count('workerqueue', ["NOT `done` AND `pid` = 0 AND `retrial` > ?", 0]);
@@ -243,7 +248,7 @@ class Worker
 	 * @return integer Number of non executed entries in the worker queue
 	 * @throws \Exception
 	 */
-	private static function totalEntries()
+	private static function totalEntries(): int
 	{
 		$stamp = (float)microtime(true);
 		$count = DBA::count('workerqueue', ['done' => false, 'pid' => 0]);
@@ -258,7 +263,7 @@ class Worker
 	 * @return integer Number of active worker processes
 	 * @throws \Exception
 	 */
-	private static function highestPriority()
+	private static function highestPriority(): int
 	{
 		$stamp = (float)microtime(true);
 		$condition = ["`pid` = 0 AND NOT `done` AND `next_try` < ?", DateTimeFormat::utcNow()];
@@ -279,7 +284,7 @@ class Worker
 	 * @return integer Is there a process running with that priority?
 	 * @throws \Exception
 	 */
-	private static function processWithPriorityActive($priority)
+	private static function processWithPriorityActive(int $priority): int
 	{
 		$condition = ["`priority` <= ? AND `pid` != 0 AND NOT `done`", $priority];
 		return DBA::exists('workerqueue', $condition);
@@ -288,41 +293,31 @@ class Worker
 	/**
 	 * Checks if the given file is valid to be included
 	 *
-	 * @param mixed $file 
-	 * @return bool 
+	 * @param mixed $file
+	 * @return bool
 	 */
-	private static function validateInclude(&$file)
+	private static function validateInclude(&$file): bool
 	{
 		$orig_file = $file;
-	
+
 		$file = realpath($file);
-	
+
 		if (strpos($file, getcwd()) !== 0) {
 			return false;
 		}
-	
-		$file = str_replace(getcwd() . "/", "", $file, $count);
+
+		$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 $valid;
+
+		return (strpos($file, 'addon/') === 0);
 	}
-	
+
 	/**
 	 * Execute a worker entry
 	 *
@@ -331,25 +326,25 @@ class Worker
 	 * @return boolean "true" if further processing should be stopped
 	 * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 	 */
-	public static function execute($queue)
+	public static function execute(array $queue): bool
 	{
 		$mypid = getmypid();
 
 		// Quit when in maintenance
 		if (DI::config()->get('system', 'maintenance', false, true)) {
-			Logger::notice("Maintenance mode - quit process", ['pid' => $mypid]);
+			Logger::notice('Maintenance mode - quit process', ['pid' => $mypid]);
 			return false;
 		}
 
 		// Constantly check the number of parallel database processes
 		if (DI::system()->isMaxProcessesReached()) {
-			Logger::warning("Max processes reached for process", ['pid' => $mypid]);
+			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::warning("Max connection reached for process", ['pid' => $mypid]);
+			Logger::warning('Max connection reached for process', ['pid' => $mypid]);
 			return false;
 		}
 
@@ -373,7 +368,7 @@ class Worker
 		if (method_exists(sprintf('Friendica\Worker\%s', $include), 'execute')) {
 			// We constantly update the "executed" date every minute to avoid being killed too soon
 			if (!isset(self::$last_update)) {
-				self::$last_update = strtotime($queue["executed"]);
+				self::$last_update = strtotime($queue['executed']);
 			}
 
 			$age = (time() - self::$last_update) / 60;
@@ -401,15 +396,10 @@ class Worker
 			return true;
 		}
 
-		// The script could be provided as full path or only with the function name
-		if ($include == basename($include)) {
-			$include = "include/".$include.".php";
-		}
-
 		if (!self::validateInclude($include)) {
-			Logger::warning("Include file is not valid", ['file' => $argv[0]]);
+			Logger::warning('Include file is not valid', ['file' => $argv[0]]);
 			$stamp = (float)microtime(true);
-			DBA::delete('workerqueue', ['id' => $queue["id"]]);
+			DBA::delete('workerqueue', ['id' => $queue['id']]);
 			self::$db_duration = (microtime(true) - $stamp);
 			self::$db_duration_write += (microtime(true) - $stamp);
 			return true;
@@ -417,12 +407,12 @@ class Worker
 
 		require_once $include;
 
-		$funcname = str_replace(".php", "", basename($argv[0]))."_run";
+		$funcname = str_replace('.php', '', basename($argv[0])) .'_run';
 
 		if (function_exists($funcname)) {
 			// We constantly update the "executed" date every minute to avoid being killed too soon
 			if (!isset(self::$last_update)) {
-				self::$last_update = strtotime($queue["executed"]);
+				self::$last_update = strtotime($queue['executed']);
 			}
 
 			$age = (time() - self::$last_update) / 60;
@@ -438,15 +428,15 @@ class Worker
 			self::execFunction($queue, $funcname, $argv, false);
 
 			$stamp = (float)microtime(true);
-			if (DBA::update('workerqueue', ['done' => true], ['id' => $queue["id"]])) {
+			if (DBA::update('workerqueue', ['done' => true], ['id' => $queue['id']])) {
 				DI::config()->set('system', 'last_worker_execution', DateTimeFormat::utcNow());
 			}
 			self::$db_duration = (microtime(true) - $stamp);
 			self::$db_duration_write += (microtime(true) - $stamp);
 		} else {
-			Logger::warning("Function does not exist", ['function' => $funcname]);
+			Logger::warning('Function does not exist', ['function' => $funcname]);
 			$stamp = (float)microtime(true);
-			DBA::delete('workerqueue', ['id' => $queue["id"]]);
+			DBA::delete('workerqueue', ['id' => $queue['id']]);
 			self::$db_duration = (microtime(true) - $stamp);
 			self::$db_duration_write += (microtime(true) - $stamp);
 		}
@@ -454,6 +444,95 @@ class Worker
 		return true;
 	}
 
+	/**
+	 * Checks if system limits are reached.
+	 *
+	 * @return boolean
+	 */
+	private static function systemLimitReached(): bool
+	{
+		$load_cooldown      = DI::config()->get('system', 'worker_load_cooldown');
+		$processes_cooldown = DI::config()->get('system', 'worker_processes_cooldown');
+
+		if ($load_cooldown == 0) {
+			$load_cooldown = DI::config()->get('system', 'maxloadavg');
+		}
+
+		if (($load_cooldown == 0) && ($processes_cooldown == 0)) {
+			return false;
+		}
+
+		$load = System::getLoadAvg();
+		if (empty($load)) {
+			return false;
+		}
+
+		if (($load_cooldown > 0) && ($load['average1'] > $load_cooldown)) {
+			return true;
+		}
+
+		if (($processes_cooldown > 0) && ($load['scheduled'] > $processes_cooldown)) {
+			return true;
+		}
+
+		return false;
+	}
+
+	/**
+	 * Slow the execution down if the system load is too high
+	 *
+	 * @return void
+	 */
+	public static function coolDown()
+	{
+		$cooldown = DI::config()->get('system', 'worker_cooldown', 0);
+		if ($cooldown > 0) {
+			Logger::debug('Wait for cooldown.', ['cooldown' => $cooldown]);
+			if ($cooldown < 1) {
+				usleep($cooldown * 1000000);
+			} else {
+				sleep($cooldown);
+			}
+		}
+
+		$load_cooldown      = DI::config()->get('system', 'worker_load_cooldown');
+		$processes_cooldown = DI::config()->get('system', 'worker_processes_cooldown');
+
+		if ($load_cooldown == 0) {
+			$load_cooldown = DI::config()->get('system', 'maxloadavg');
+		}
+
+		if (($load_cooldown == 0) && ($processes_cooldown == 0)) {
+			return;
+		}
+
+		$sleeping = false;
+
+		while ($load = System::getLoadAvg()) {
+			if (($load_cooldown > 0) && ($load['average1'] > $load_cooldown)) {
+				if (!$sleeping) {
+					Logger::notice('Load induced pre execution cooldown.', ['max' => $load_cooldown, 'load' => $load, 'called-by' => System::callstack(1)]);
+					$sleeping = true;
+				}
+				sleep(1);
+				continue;
+			}
+			if (($processes_cooldown > 0) && ($load['scheduled'] > $processes_cooldown)) {
+				if (!$sleeping) {
+					Logger::notice('Process induced pre execution cooldown.', ['max' => $processes_cooldown, 'load' => $load, 'called-by' => System::callstack(1)]);
+					$sleeping = true;
+				}
+				sleep(1);
+				continue;
+			}
+			break;
+		}
+
+		if ($sleeping) {
+			Logger::notice('Cooldown ended.', ['max-load' => $load_cooldown, 'max-processes' => $processes_cooldown, 'load' => $load, 'called-by' => System::callstack(1)]);
+		}
+	}
+
 	/**
 	 * Execute a function from the queue
 	 *
@@ -464,19 +543,15 @@ class Worker
 	 * @return void
 	 * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 	 */
-	private static function execFunction($queue, $funcname, $argv, $method_call)
+	private static function execFunction(array $queue, string $funcname, array $argv, bool $method_call)
 	{
 		$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);
-		}
+		self::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);
 
@@ -484,11 +559,6 @@ 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;
-		}
-
 		$a->setQueue($queue);
 
 		$up_duration = microtime(true) - self::$up_start;
@@ -525,6 +595,8 @@ class Worker
 
 		Logger::info('Performance:', ['state' => self::$state, 'count' => $dbcount, 'stat' => $dbstat, 'write' => $dbwrite, 'lock' => $dblock, 'total' => $dbtotal, 'rest' => $rest, 'exec' => $exec]);
 
+		self::coolDown();
+
 		self::$up_start = microtime(true);
 		self::$db_duration = 0;
 		self::$db_duration_count = 0;
@@ -533,23 +605,18 @@ class Worker
 		self::$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"] . ": " . $funcname);
-
-		if ($cooldown > 0) {
-			Logger::info('Post execution cooldown.', ['priority' => $queue['priority'], 'id' => $queue["id"], 'cooldown' => $cooldown]);
-			sleep($cooldown);
-		}
+		DI::profiler()->saveLog(DI::logger(), 'ID ' . $queue['id'] . ': ' . $funcname);
 	}
 
 	/**
@@ -558,19 +625,19 @@ class Worker
 	 * @return bool Are more than 3/4 of the maximum connections used?
 	 * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 	 */
-	private static function maxConnectionsReached()
+	private static function maxConnectionsReached(): bool
 	{
 		// Fetch the max value from the config. This is needed when the system cannot detect the correct value by itself.
-		$max = DI::config()->get("system", "max_connections");
+		$max = DI::config()->get('system', 'max_connections');
 
 		// Fetch the percentage level where the worker will get active
-		$maxlevel = DI::config()->get("system", "max_connections_level", 75);
+		$maxlevel = DI::config()->get('system', 'max_connections_level', 75);
 
 		if ($max == 0) {
 			// the maximum number of possible user connections can be a system variable
 			$r = DBA::fetchFirst("SHOW VARIABLES WHERE `variable_name` = 'max_user_connections'");
 			if (DBA::isResult($r)) {
-				$max = $r["Value"];
+				$max = $r['Value'];
 			}
 			// Or it can be granted. This overrides the system variable
 			$stamp = (float)microtime(true);
@@ -596,12 +663,12 @@ class Worker
 			$used = DBA::numRows($r);
 			DBA::close($r);
 
-			Logger::info("Connection usage (user values)", ['usage' => $used, 'max' => $max]);
+			Logger::info('Connection usage (user values)', ['usage' => $used, 'max' => $max]);
 
 			$level = ($used / $max) * 100;
 
 			if ($level >= $maxlevel) {
-				Logger::warning("Maximum level (".$maxlevel."%) of user connections reached: ".$used."/".$max);
+				Logger::warning('Maximum level (' . $maxlevel . '%) of user connections reached: ' . $used .'/' . $max);
 				return true;
 			}
 		}
@@ -612,7 +679,7 @@ class Worker
 		if (!DBA::isResult($r)) {
 			return false;
 		}
-		$max = intval($r["Value"]);
+		$max = intval($r['Value']);
 		if ($max == 0) {
 			return false;
 		}
@@ -620,103 +687,21 @@ class Worker
 		if (!DBA::isResult($r)) {
 			return false;
 		}
-		$used = intval($r["Value"]);
+		$used = intval($r['Value']);
 		if ($used == 0) {
 			return false;
 		}
-		Logger::info("Connection usage (system values)", ['used' => $used, 'max' => $max]);
+		Logger::info('Connection usage (system values)', ['used' => $used, 'max' => $max]);
 
 		$level = $used / $max * 100;
 
 		if ($level < $maxlevel) {
 			return false;
 		}
-		Logger::warning("Maximum level (".$level."%) of system connections reached: ".$used."/".$max);
+		Logger::warning('Maximum level (' . $level . '%) of system connections reached: ' . $used . '/' . $max);
 		return true;
 	}
 
-	/**
-	 * fix the queue entry if the worker process died
-	 *
-	 * @return void
-	 * @throws \Exception
-	 */
-	private static function killStaleWorkers()
-	{
-		$stamp = (float)microtime(true);
-		$entries = DBA::select(
-			'workerqueue',
-			['id', 'pid', 'executed', 'priority', 'command', 'parameter'],
-			['NOT `done` AND `pid` != 0'],
-			['order' => ['priority', 'retrial', 'created']]
-		);
-		self::$db_duration += (microtime(true) - $stamp);
-
-		while ($entry = DBA::fetch($entries)) {
-			if (!posix_kill($entry["pid"], 0)) {
-				$stamp = (float)microtime(true);
-				DBA::update(
-					'workerqueue',
-					['executed' => DBA::NULL_DATETIME, 'pid' => 0],
-					['id' => $entry["id"]]
-				);
-				self::$db_duration += (microtime(true) - $stamp);
-				self::$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'], PRIORITIES)) {
-					Logger::warning('Invalid priority', ['entry' => $entry, 'callstack' => System::callstack(20)]);
-					$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']];
-
-				$argv = json_decode($entry['parameter'], true);
-				if (!empty($entry['command'])) {
-					$command = $entry['command'];
-				} elseif (!empty($argv)) {
-					$command = array_shift($argv);
-				} else {
-					return;
-				}
-
-				$command = basename($command);
-
-				// How long is the process already running?
-				$duration = (time() - strtotime($entry["executed"])) / 60;
-				if ($duration > $max_duration) {
-					Logger::notice('Worker process took too much time - killed', ['duration' => number_format($duration, 3), 'max' => $max_duration, 'id' => $entry["id"], 'pid' => $entry["pid"], 'command' => $command]);
-					posix_kill($entry["pid"], SIGTERM);
-
-					// 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) {
-						$new_priority = PRIORITY_MEDIUM;
-					} elseif ($entry['priority'] == PRIORITY_MEDIUM) {
-						$new_priority = PRIORITY_LOW;
-					} elseif ($entry['priority'] != PRIORITY_CRITICAL) {
-						$new_priority = PRIORITY_NEGLIGIBLE;
-					}
-					$stamp = (float)microtime(true);
-					DBA::update(
-						'workerqueue',
-						['executed' => DBA::NULL_DATETIME, 'created' => DateTimeFormat::utcNow(), 'priority' => $new_priority, 'pid' => 0],
-						['id' => $entry["id"]]
-					);
-					self::$db_duration += (microtime(true) - $stamp);
-					self::$db_duration_write += (microtime(true) - $stamp);
-				} else {
-					Logger::info('Process runtime is okay', ['duration' => number_format($duration, 3), 'max' => $max_duration, 'id' => $entry["id"], 'pid' => $entry["pid"], 'command' => $command]);
-				}
-			}
-		}
-		DBA::close($entries);
-	}
 
 	/**
 	 * Checks if the number of active workers exceeds the given limits
@@ -724,9 +709,9 @@ class Worker
 	 * @return bool Are there too much workers running?
 	 * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 	 */
-	private static function tooMuchWorkers()
+	private static function tooMuchWorkers(): bool
 	{
-		$queues = DI::config()->get("system", "worker_queues", 10);
+		$queues = DI::config()->get('system', 'worker_queues', 10);
 
 		$maxqueues = $queues;
 
@@ -735,7 +720,7 @@ class Worker
 		// Decrease the number of workers at higher load
 		$load = System::currentLoad();
 		if ($load) {
-			$maxsysload = intval(DI::config()->get("system", "maxloadavg", 20));
+			$maxsysload = intval(DI::config()->get('system', 'maxloadavg', 20));
 
 			/* Default exponent 3 causes queues to rapidly decrease as load increases.
 			 * If you have 20 max queues at idle, then you get only 5 queues at 37.1% of $maxsysload.
@@ -787,8 +772,8 @@ class Worker
 					self::$db_duration += (microtime(true) - $stamp);
 					self::$db_duration_stat += (microtime(true) - $stamp);
 					$idle_workers -= $running;
-					$waiting_processes += $entry["entries"];
-					$listitem[$entry['priority']] = $entry['priority'] . ":" . $running . "/" . $entry["entries"];
+					$waiting_processes += $entry['entries'];
+					$listitem[$entry['priority']] = $entry['priority'] . ':' . $running . '/' . $entry['entries'];
 				}
 				DBA::close($jobs);
 			} else {
@@ -799,35 +784,35 @@ class Worker
 				self::$db_duration_stat += (microtime(true) - $stamp);
 
 				while ($entry = DBA::fetch($jobs)) {
-					$idle_workers -= $entry["running"];
-					$listitem[$entry['priority']] = $entry['priority'].":".$entry["running"];
+					$idle_workers -= $entry['running'];
+					$listitem[$entry['priority']] = $entry['priority'] . ':' . $entry['running'];
 				}
 				DBA::close($jobs);
 			}
 
 			$waiting_processes -= $deferred;
 
-			$listitem[0] = "0:" . max(0, $idle_workers);
+			$listitem[0] = '0:' . max(0, $idle_workers);
 
 			$processlist .= ' ('.implode(', ', $listitem).')';
 
-			if (DI::config()->get("system", "worker_fastlane", false) && ($queues > 0) && ($active >= $queues) && self::entriesExists()) {
+			if (DI::config()->get('system', 'worker_fastlane', false) && ($queues > 0) && ($active >= $queues) && self::entriesExists()) {
 				$top_priority = self::highestPriority();
 				$high_running = self::processWithPriorityActive($top_priority);
 
-				if (!$high_running && ($top_priority > PRIORITY_UNDEFINED) && ($top_priority < PRIORITY_NEGLIGIBLE)) {
-					Logger::info("Jobs with a higher priority are waiting but none is executed. Open a fastlane.", ['priority' => $top_priority]);
+				if (!$high_running && ($top_priority > self::PRIORITY_UNDEFINED) && ($top_priority < self::PRIORITY_NEGLIGIBLE)) {
+					Logger::info('Jobs with a higher priority are waiting but none is executed. Open a fastlane.', ['priority' => $top_priority]);
 					$queues = $active + 1;
 				}
 			}
 
-			Logger::notice("Load: " . $load ."/" . $maxsysload . " - processes: " . $deferred . "/" . $active . "/" . $waiting_processes . $processlist . " - maximum: " . $queues . "/" . $maxqueues);
+			Logger::notice('Load: ' . $load . '/' . $maxsysload . ' - processes: ' . $deferred . '/' . $active . '/' . $waiting_processes . $processlist . ' - maximum: ' . $queues . '/' . $maxqueues);
 
 			// 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' => $queues]);
-				if (self::isDaemonMode()) {
-					self::IPCSetJobState(true);
+			if (!DI::config()->get('system', 'worker_dont_fork', false) && ($queues > ($active + 1)) && self::entriesExists() && !self::systemLimitReached()) {
+				Logger::info('There are fewer workers as possible, fork a new worker.', ['active' => $active, 'queues' => $queues]);
+				if (Worker\Daemon::isMode()) {
+					Worker\IPC::SetJobState(true);
 				} else {
 					self::spawnWorker();
 				}
@@ -835,8 +820,8 @@ class Worker
 		}
 
 		// if there are too much worker, we don't spawn a new one.
-		if (self::isDaemonMode() && ($active > $queues)) {
-			self::IPCSetJobState(false);
+		if (Worker\Daemon::isMode() && ($active > $queues)) {
+			Worker\IPC::SetJobState(false);
 		}
 
 		return $active > $queues;
@@ -848,7 +833,7 @@ class Worker
 	 * @return integer Number of active worker processes
 	 * @throws \Exception
 	 */
-	private static function activeWorkers()
+	private static function activeWorkers(): int
 	{
 		$stamp = (float)microtime(true);
 		$count = DI::process()->countCommand('Worker.php');
@@ -863,7 +848,7 @@ class Worker
 	 * @return array List of worker process ids
 	 * @throws \Exception
 	 */
-	private static function getWorkerPIDList()
+	private static function getWorkerPIDList(): array
 	{
 		$ids = [];
 		$stamp = (float)microtime(true);
@@ -884,7 +869,7 @@ class Worker
 	/**
 	 * Returns waiting jobs for the current process id
 	 *
-	 * @return array waiting workerqueue jobs
+	 * @return array|bool waiting workerqueue jobs or FALSE on failture
 	 * @throws \Exception
 	 */
 	private static function getWaitingJobForPID()
@@ -906,7 +891,7 @@ class Worker
 	 * @return array array with next jobs
 	 * @throws \Exception
 	 */
-	private static function nextProcess(int $limit)
+	private static function nextProcess(int $limit): array
 	{
 		$priority = self::nextPriority();
 		if (empty($priority)) {
@@ -941,13 +926,13 @@ class Worker
 	/**
 	 * Returns the priority of the next workerqueue job
 	 *
-	 * @return string priority
+	 * @return string|bool priority or FALSE on failure
 	 * @throws \Exception
 	 */
 	private static function nextPriority()
 	{
 		$waiting = [];
-		$priorities = [PRIORITY_CRITICAL, PRIORITY_HIGH, PRIORITY_MEDIUM, PRIORITY_LOW, PRIORITY_NEGLIGIBLE];
+		$priorities = [self::PRIORITY_CRITICAL, self::PRIORITY_HIGH, self::PRIORITY_MEDIUM, self::PRIORITY_LOW, self::PRIORITY_NEGLIGIBLE];
 		foreach ($priorities as $priority) {
 			$stamp = (float)microtime(true);
 			if (DBA::exists('workerqueue', ["`priority` = ? AND `pid` = 0 AND NOT `done` AND `next_try` < ?", $priority, DateTimeFormat::utcNow()])) {
@@ -956,8 +941,8 @@ class Worker
 			self::$db_duration += (microtime(true) - $stamp);
 		}
 
-		if (!empty($waiting[PRIORITY_CRITICAL])) {
-			return PRIORITY_CRITICAL;
+		if (!empty($waiting[self::PRIORITY_CRITICAL])) {
+			return self::PRIORITY_CRITICAL;
 		}
 
 		$running = [];
@@ -1012,7 +997,7 @@ class Worker
 	/**
 	 * Find and claim the next worker process for us
 	 *
-	 * @return boolean Have we found something?
+	 * @return void
 	 * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 	 */
 	private static function findWorkerProcesses()
@@ -1090,7 +1075,7 @@ class Worker
 	 * @return array worker processes
 	 * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 	 */
-	public static function workerProcess()
+	public static function workerProcess(): array
 	{
 		// There can already be jobs for us in the queue.
 		$waiting = self::getWaitingJobForPID();
@@ -1100,7 +1085,7 @@ class Worker
 
 		$stamp = (float)microtime(true);
 		if (!DI::lock()->acquire(self::LOCK_PROCESS)) {
-			return false;
+			return [];
 		}
 		self::$lock_duration += (microtime(true) - $stamp);
 
@@ -1108,7 +1093,9 @@ class Worker
 
 		DI::lock()->release(self::LOCK_PROCESS);
 
-		return self::getWaitingJobForPID();
+		// Prevents "Return value of Friendica\Core\Worker::workerProcess() must be of the type array, bool returned"
+		$process = self::getWaitingJobForPID();
+		return (is_array($process) ? $process : []);
 	}
 
 	/**
@@ -1127,26 +1114,6 @@ class Worker
 		self::$db_duration_write += (microtime(true) - $stamp);
 	}
 
-	/**
-	 * Runs the cron processes
-	 *
-	 * @return void
-	 * @throws \Friendica\Network\HTTPException\InternalServerErrorException
-	 */
-	private static function runCron()
-	{
-		Logger::info('Add cron entries');
-
-		// 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();
-	}
-
 	/**
 	 * Fork a child process
 	 *
@@ -1172,11 +1139,11 @@ class Worker
 			// The parent process continues here
 			DBA::connect();
 
-			self::IPCSetJobState(true, $pid);
+			Worker\IPC::SetJobState(true, $pid);
 			Logger::info('Spawned new worker', ['pid' => $pid]);
 
 			$cycles = 0;
-			while (self::IPCJobsExists($pid) && (++$cycles < 100)) {
+			while (Worker\IPC::JobsExists($pid) && (++$cycles < 100)) {
 				usleep(10000);
 			}
 
@@ -1191,7 +1158,7 @@ class Worker
 		$process = DI::process()->create(getmypid(), basename(__FILE__));
 
 		$cycles = 0;
-		while (!self::IPCJobsExists($process->pid) && (++$cycles < 100)) {
+		while (!Worker\IPC::JobsExists($process->pid) && (++$cycles < 100)) {
 			usleep(10000);
 		}
 
@@ -1201,7 +1168,7 @@ class Worker
 
 		self::unclaimProcess($process);
 
-		self::IPCSetJobState(false, $process->pid);
+		Worker\IPC::SetJobState(false, $process->pid);
 		DI::process()->delete($process);
 		Logger::info('Worker ended', ['pid' => $process->pid]);
 		exit();
@@ -1214,15 +1181,15 @@ class Worker
 	 * @return void
 	 * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 	 */
-	public static function spawnWorker($do_cron = false)
+	public static function spawnWorker(bool $do_cron = false)
 	{
-		if (self::isDaemonMode() && DI::config()->get('system', 'worker_fork')) {
+		if (Worker\Daemon::isMode() && DI::config()->get('system', 'worker_fork')) {
 			self::forkProcess($do_cron);
 		} else {
 			DI::system()->run('bin/worker.php', ['no_cron' => !$do_cron]);
 		}
-		if (self::isDaemonMode()) {
-			self::IPCSetJobState(false);
+		if (Worker\Daemon::isMode()) {
+			Worker\IPC::SetJobState(false);
 		}
 	}
 
@@ -1232,12 +1199,12 @@ class Worker
 	 * @param (integer|array) priority or parameter array, strings are deprecated and are ignored
 	 *
 	 * next args are passed as $cmd command line
-	 * or: Worker::add(PRIORITY_HIGH, "Notifier", Delivery::DELETION, $drop_id);
-	 * or: Worker::add(array('priority' => PRIORITY_HIGH, 'dont_fork' => true), "Delivery", $post_id);
+	 * or: Worker::add(Worker::PRIORITY_HIGH, 'Notifier', Delivery::DELETION, $drop_id);
+	 * or: Worker::add(array('priority' => Worker::PRIORITY_HIGH, 'dont_fork' => true), 'Delivery', $post_id);
 	 *
-	 * @return int "0" if worker queue entry already existed or there had been an error, otherwise the ID of the worker task
+	 * @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 ""
+	 * @note $cmd and string args are surrounded with ''
 	 *
 	 * @hooks 'proc_run'
 	 *    array $arr
@@ -1251,14 +1218,14 @@ class Worker
 
 		$arr = ['args' => $args, 'run_cmd' => true];
 
-		Hook::callAll("proc_run", $arr);
+		Hook::callAll('proc_run', $arr);
 		if (!$arr['run_cmd'] || !count($args)) {
 			return 1;
 		}
 
-		$priority = PRIORITY_MEDIUM;
+		$priority = self::PRIORITY_MEDIUM;
 		// Don't fork from frontend tasks by default
-		$dont_fork = DI::config()->get("system", "worker_dont_fork", false) || !DI::mode()->isBackend();
+		$dont_fork = DI::config()->get('system', 'worker_dont_fork', false) || !DI::mode()->isBackend();
 		$created = DateTimeFormat::utcNow();
 		$delayed = DBA::NULL_DATETIME;
 		$force_priority = false;
@@ -1292,9 +1259,9 @@ class Worker
 		$found = DBA::exists('workerqueue', ['command' => $command, 'parameter' => $parameters, 'done' => false]);
 		$added = 0;
 
-		if (!in_array($priority, PRIORITIES)) {
+		if (!is_int($priority) || !in_array($priority, self::PRIORITIES)) {
 			Logger::warning('Invalid priority', ['priority' => $priority, 'command' => $command, 'callstack' => System::callstack(20)]);
-			$priority = PRIORITY_MEDIUM;
+			$priority = self::PRIORITY_MEDIUM;
 		}
 
 		// Quit if there was a database error - a precaution for the update process to 3.5.3
@@ -1313,14 +1280,14 @@ class Worker
 		}
 
 		// Set the IPC flag to ensure an immediate process execution via daemon
-		if (self::isDaemonMode()) {
-			self::IPCSetJobState(true);
+		if (Worker\Daemon::isMode()) {
+			Worker\IPC::SetJobState(true);
 		}
 
-		self::checkDaemonState();
+		Worker\Daemon::checkState();
 
 		// Should we quit and wait for the worker to be called as a cronjob?
-		if ($dont_fork) {
+		if ($dont_fork || self::systemLimitReached()) {
 			return $added;
 		}
 
@@ -1338,7 +1305,7 @@ class Worker
 		}
 
 		// Quit on daemon mode
-		if (self::isDaemonMode()) {
+		if (Worker\Daemon::isMode()) {
 			return $added;
 		}
 
@@ -1348,7 +1315,7 @@ class Worker
 		return $added;
 	}
 
-	public static function countWorkersByCommand(string $command)
+	public static function countWorkersByCommand(string $command): int
 	{
 		return DBA::count('workerqueue', ['done' => false, 'pid' => 0, 'command' => $command]);
 	}
@@ -1361,7 +1328,7 @@ class Worker
 	 * @param integer $max_level maximum retrial level
 	 * @return integer the next retrial level value
 	 */
-	private static function getNextRetrial($queue, $max_level)
+	private static function getNextRetrial(array $queue, int $max_level): int
 	{
 		$created = strtotime($queue['created']);
 		$retrial_time = time() - $created;
@@ -1396,11 +1363,6 @@ class Worker
 		$id = $queue['id'];
 		$priority = $queue['priority'];
 
-		if (!in_array($priority, PRIORITIES)) {
-			Logger::warning('Invalid priority', ['queue' => $queue, 'callstack' => System::callstack(20)]);
-			$priority = PRIORITY_MEDIUM;
-		}
-
 		$max_level = DI::config()->get('system', 'worker_defer_limit');
 
 		$new_retrial = self::getNextRetrial($queue, $max_level);
@@ -1414,12 +1376,12 @@ class Worker
 		$delay = (($new_retrial + 2) ** 4) + (rand(1, 30) * ($new_retrial));
 		$next = DateTimeFormat::utc('now + ' . $delay . ' seconds');
 
-		if (($priority < PRIORITY_MEDIUM) && ($new_retrial > 3)) {
-			$priority = PRIORITY_MEDIUM;
-		} elseif (($priority < PRIORITY_LOW) && ($new_retrial > 6)) {
-			$priority = PRIORITY_LOW;
-		} elseif (($priority < PRIORITY_NEGLIGIBLE) && ($new_retrial > 8)) {
-			$priority = PRIORITY_NEGLIGIBLE;
+		if (($priority < self::PRIORITY_MEDIUM) && ($new_retrial > 3)) {
+			$priority = self::PRIORITY_MEDIUM;
+		} elseif (($priority < self::PRIORITY_LOW) && ($new_retrial > 6)) {
+			$priority = self::PRIORITY_LOW;
+		} elseif (($priority < self::PRIORITY_NEGLIGIBLE) && ($new_retrial > 8)) {
+			$priority = self::PRIORITY_NEGLIGIBLE;
 		}
 
 		Logger::info('Deferred task', ['id' => $id, 'retrial' => $new_retrial, 'created' => $queue['created'], 'next_execution' => $next, 'old_prio' => $queue['priority'], 'new_prio' => $priority]);
@@ -1433,165 +1395,13 @@ class Worker
 		return true;
 	}
 
-	/**
-	 * 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 IPCDeleteJobState(int $key)
-	{
-		$stamp = (float)microtime(true);
-		DBA::delete('worker-ipc', ['key' => $key]);
-		self::$db_duration += (microtime(true) - $stamp);
-		self::$db_duration_write += (microtime(true) - $stamp);
-	}
-
-	/**
-	 * Checks if some worker job waits to be executed
-	 *
-	 * @param int $key Key number
-	 * @return bool
-	 * @throws \Exception
-	 */
-	public static function IPCJobsExists(int $key = 0)
-	{
-		$stamp = (float)microtime(true);
-		$row = DBA::selectFirst('worker-ipc', ['jobs'], ['key' => $key]);
-		self::$db_duration += (microtime(true) - $stamp);
-
-		// When we don't have a row, no job is running
-		if (!DBA::isResult($row)) {
-			return false;
-		}
-
-		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
-	 *
-	 * @return void
-	 */
-	private static function checkDaemonState()
-	{
-		if (!DI::config()->get('system', 'daemon_watchdog', false)) {
-			return;
-		}
-
-		if (!DI::mode()->isNormal()) {
-			return;
-		}
-
-		// Check every minute if the daemon is running
-		if (DI::config()->get('system', 'last_daemon_check', 0) + 60 > time()) {
-			return;
-		}
-
-		DI::config()->set('system', 'last_daemon_check', time());
-
-		$pidfile = DI::config()->get('system', 'pidfile');
-		if (empty($pidfile)) {
-			// No pid file, no daemon
-			return;
-		}
-
-		if (!is_readable($pidfile)) {
-			// No pid file. We assume that the daemon had been intentionally stopped.
-			return;
-		}
-
-		$pid = intval(file_get_contents($pidfile));
-		if (posix_kill($pid, 0)) {
-			Logger::info('Daemon process is running', ['pid' => $pid]);
-			return;
-		}
-
-		Logger::warning('Daemon process is not running', ['pid' => $pid]);
-
-		self::spawnDaemon();
-	}
-
-	/**
-	 * Spawn a new daemon process
-	 *
-	 * @return void
-	 */
-	private static function spawnDaemon()
-	{
-		Logger::notice('Starting new daemon process');
-		$command = 'bin/daemon.php';
-		$a = DI::app();
-		DI::system()->run($command, ['start']);
-		Logger::notice('New daemon process started');
-	}
-
 	/**
 	 * Check if the system is inside the defined maintenance window
 	 *
+	 * @param bool $check_last_execution Whether check last execution
 	 * @return boolean
 	 */
-	public static function isInMaintenanceWindow(bool $check_last_execution = false)
+	public static function isInMaintenanceWindow(bool $check_last_execution = false): bool
 	{
 		// Calculate the seconds of the start end end of the maintenance window
 		$start = strtotime(DI::config()->get('system', 'maintenance_start')) % 86400;