Merge pull request #5223 from annando/fast-daemon

Multiple daemon improvements (foreground, faster spawning)

bin/daemon.php

@@ -52,6 +52,8 @@ if (in_array("status", $_SERVER["argv"])) {
 	$mode = "status";
 }
 
+$foreground = in_array("--foreground", $_SERVER["argv"]);
+
 if (!isset($mode)) {
 	die("Please use either 'start', 'stop' or 'status'.\n");
 }
@@ -94,31 +96,38 @@ if (!empty($pid) && posix_kill($pid, 0)) {
 }
 
 logger('Starting worker daemon.', LOGGER_DEBUG);
-echo "Starting worker daemon.\n";
 
-// Switch over to daemon mode.
+if (!$foreground) {
-if ($pid = pcntl_fork()) {
+	echo "Starting worker daemon.\n";
+
+	// Switch over to daemon mode.
+	if ($pid = pcntl_fork()) {
 		return;     // Parent
-}
+	}
 
-fclose(STDIN);  // Close all of the standard
+	fclose(STDIN);  // Close all of the standard
-fclose(STDOUT); // file descriptors as we
+	fclose(STDOUT); // file descriptors as we
-fclose(STDERR); // are running as a daemon.
+	fclose(STDERR); // are running as a daemon.
 
-dba::disconnect();
+	dba::disconnect();
 
-register_shutdown_function('shutdown');
+	register_shutdown_function('shutdown');
 
-if (posix_setsid() < 0) {
+	if (posix_setsid() < 0) {
 		return;
-}
+	}
 
-if ($pid = pcntl_fork()) {
+	if ($pid = pcntl_fork()) {
 		return;     // Parent
+	}
+
+	$pid = getmypid();
+	file_put_contents($pidfile, $pid);
+
+	// We lose the database connection upon forking
+	dba::connect($db_host, $db_user, $db_pass, $db_data);
 }
 
-// We lose the database connection upon forking
-dba::connect($db_host, $db_user, $db_pass, $db_data);
 unset($db_host, $db_user, $db_pass, $db_data);
 
 Config::set('system', 'worker_daemon_mode', true);
@@ -126,9 +135,6 @@ Config::set('system', 'worker_daemon_mode', true);
 // Just to be sure that this script really runs endlessly
 set_time_limit(0);
 
-$pid = getmypid();
-file_put_contents($pidfile, $pid);
-
 $wait_interval = intval(Config::get('system', 'cron_interval', 5)) * 60;
 
 $do_cron = true;
@@ -152,12 +158,21 @@ while (true) {
 	}
 
 	logger("Sleeping", LOGGER_DEBUG);
-	$i = 0;
+	$start = time();
 	do {
-		sleep(1);
+		$seconds = (time() - $start);
-	} while (($i++ < $wait_interval) && !Worker::IPCJobsExists());
 
-	if ($i >= $wait_interval) {
+		// logarithmic wait time calculation.
+		// Background: After jobs had been started, they often fork many workers.
+		// To not waste too much time, the sleep period increases.
+		$arg = (($seconds + 1) / ($wait_interval / 9)) + 1;
+		$sleep = round(log10($arg) * 1000000, 0);
+		usleep($sleep);
+
+		$timeout = ($seconds >= $wait_interval);
+	} while (!$timeout && !Worker::IPCJobsExists());
+
+	if ($timeout) {
 		$do_cron = true;
 		logger("Woke up after $wait_interval seconds.", LOGGER_DEBUG);
 	} else {

src/Core/Worker.php

@@ -53,11 +53,6 @@ class Worker
 		// We now start the process. This is done after the load check since this could increase the load.
 		self::startProcess();
 
-		// The daemon doesn't need to fork new workers anymore, since we started a process
-		if (Config::get('system', 'worker_daemon_mode', false)) {
-			self::IPCSetJobState(false);
-		}
-
 		// Kill stale processes every 5 minutes
 		$last_cleanup = Config::get('system', 'worker_last_cleaned', 0);
 		if (time() > ($last_cleanup + 300)) {
@@ -145,6 +140,8 @@ class Worker
 				return;
 			}
 		}
+
+		// Cleaning up. Possibly not needed, but it doesn't harm anything.
 		if (Config::get('system', 'worker_daemon_mode', false)) {
 			self::IPCSetJobState(false);
 		}
@@ -698,9 +695,18 @@ class Worker
 			// Are there fewer workers running as possible? Then fork a new one.
 			if (!Config::get("system", "worker_dont_fork", false) && ($queues > ($active + 1)) && ($entries > 1)) {
 				logger("Active workers: ".$active."/".$queues." Fork a new worker.", LOGGER_DEBUG);
+				if (Config::get('system', 'worker_daemon_mode', false)) {
+					self::IPCSetJobState(true);
+				} else {
 					self::spawnWorker();
 				}
 			}
+		}
+
+		// if there are too much worker, we down't spawn a new one.
+		if (Config::get('system', 'worker_daemon_mode', false) && ($active >= $queues)) {
+			self::IPCSetJobState(false);
+		}
 
 		return $active >= $queues;
 	}
@@ -859,11 +865,6 @@ class Worker
 			dba::update('workerqueue', ['executed' => DateTimeFormat::utcNow(), 'pid' => $mypid], $ids);
 		}
 
-		// The daemon doesn't need to fork new workers anymore, since we are inside the worker
-		if (Config::get('system', 'worker_daemon_mode', false)) {
-			self::IPCSetJobState(false);
-		}
-
 		return $found;
 	}
 
@@ -1024,6 +1025,11 @@ class Worker
 		}
 
 		get_app()->proc_run($args);
+
+		// after spawning we have to remove the flag.
+		if (Config::get('system', 'worker_daemon_mode', false)) {
+			self::IPCSetJobState(false);
+		}
 	}
 
 	/**
@@ -1094,12 +1100,6 @@ class Worker
 			return true;
 		}
 
-		// We tell the daemon that a new job entry exists
-		if (Config::get('system', 'worker_daemon_mode', false)) {
-			self::IPCSetJobState(true);
-			return true;
-		}
-
 		// If there is a lock then we don't have to check for too much worker
 		if (!Lock::set('worker', 0)) {
 			return true;
@@ -1113,6 +1113,12 @@ class Worker
 			return true;
 		}
 
+		// We tell the daemon that a new job entry exists
+		if (Config::get('system', 'worker_daemon_mode', false)) {
+			// We don't have to set the IPC flag - this is done in "tooMuchWorkers"
+			return true;
+		}
+
 		// Now call the worker to execute the jobs that we just added to the queue
 		self::spawnWorker();