X-Git-Url: https://git.mxchange.org/?a=blobdiff_plain;f=include%2Fpoller.php;h=d43257fc9f47c912d60e9cea303b7db33eb344b0;hb=56bfb0f45a104b5bba783ff56876bbe2fb96c352;hp=8784931d3c6106652d3d542490769702f7a3e470;hpb=06815f1a38409e45b0c5e5184c081f964ec89e47;p=friendica.git

diff --git a/include/poller.php b/include/poller.php
index 8784931d3c..d43257fc9f 100644
--- a/include/poller.php
+++ b/include/poller.php
@@ -1,6 +1,7 @@
 <?php
 
 use Friendica\App;
+use Friendica\Core\System;
 use Friendica\Core\Config;
 use Friendica\Util\Lock;
 
@@ -18,7 +19,9 @@ if (!file_exists("boot.php") && (sizeof($_SERVER["argv"]) != 0)) {
 require_once("boot.php");
 
 function poller_run($argv, $argc){
-	global $a, $db;
+	global $a, $db, $poller_up_start, $poller_db_duration;
+
+	$poller_up_start = microtime(true);
 
 	$a = new App(dirname(__DIR__));
 
@@ -47,11 +50,15 @@ function poller_run($argv, $argc){
 	// We now start the process. This is done after the load check since this could increase the load.
 	$a->start_process();
 
-	// At first we check the number of workers and quit if there are too much of them
-	// This is done at the top to avoid that too much code is executed without a need to do so,
-	// since the poller mostly quits here.
-	if (poller_too_much_workers()) {
+	// Kill stale processes every 5 minutes
+	$last_cleanup = Config::get('system', 'poller_last_cleaned', 0);
+	if (time() > ($last_cleanup + 300)) {
+		Config::set('system', 'poller_last_cleaned', time());
 		poller_kill_stale_workers();
+	}
+
+	// Count active workers and compare them with a maximum value that depends on the load
+	if (poller_too_much_workers()) {
 		logger('Pre check: Active worker limit reached, quitting.', LOGGER_DEBUG);
 		return;
 	}
@@ -82,25 +89,36 @@ function poller_run($argv, $argc){
 	$starttime = time();
 
 	// We fetch the next queue entry that is about to be executed
-	while ($r = poller_worker_process()) {
+	while ($r = poller_worker_process($passing_slow)) {
 
-		// If we got that queue entry we claim it for us
-		if (!poller_claim_process($r[0])) {
-			dba::unlock();
-			continue;
-		} else {
-			// Fetch all workerqueue data while the table is still locked
-			// This is redundant, but this speeds up the processing
-			$entries = poller_total_entries();
-			$top_priority = poller_highest_priority();
-			$high_running = poller_process_with_priority_active($top_priority);
-			dba::unlock();
+		// When we are processing jobs with a lower priority, we don't refetch new jobs
+		// Otherwise fast jobs could wait behind slow ones and could be blocked.
+		$refetched = $passing_slow;
+
+		foreach ($r AS $entry) {
+			// Assure that the priority is an integer value
+			$entry['priority'] = (int)$entry['priority'];
+
+			// The work will be done
+			if (!poller_execute($entry)) {
+				logger('Process execution failed, quitting.', LOGGER_DEBUG);
+				return;
+			}
+
+			// If possible we will fetch new jobs for this worker
+			if (!$refetched && Lock::set('poller_worker_process', 0)) {
+				$stamp = (float)microtime(true);
+				$refetched = find_worker_processes($passing_slow);
+				$poller_db_duration += (microtime(true) - $stamp);
+				Lock::remove('poller_worker_process');
+			}
 		}
 
 		// To avoid the quitting of multiple pollers only one poller at a time will execute the check
 		if (Lock::set('poller_worker', 0)) {
+			$stamp = (float)microtime(true);
 			// Count active workers and compare them with a maximum value that depends on the load
-			if (poller_too_much_workers($entries, $top_priority, $high_running)) {
+			if (poller_too_much_workers()) {
 				logger('Active worker limit reached, quitting.', LOGGER_DEBUG);
 				return;
 			}
@@ -111,16 +129,11 @@ function poller_run($argv, $argc){
 				return;
 			}
 			Lock::remove('poller_worker');
+			$poller_db_duration += (microtime(true) - $stamp);
 		}
 
-		// finally the work will be done
-		if (!poller_execute($r[0])) {
-			logger('Process execution failed, quitting.', LOGGER_DEBUG);
-			return;
-		}
-
-		// Quit the poller once every hour
-		if (time() > ($starttime + 3600)) {
+		// Quit the poller once every 5 minutes
+		if (time() > ($starttime + 300)) {
 			logger('Process lifetime reached, quitting.', LOGGER_DEBUG);
 			return;
 		}
@@ -134,8 +147,12 @@ function poller_run($argv, $argc){
  * @return integer Number of non executed entries in the worker queue
  */
 function poller_total_entries() {
-	$s = q("SELECT COUNT(*) AS `total` FROM `workerqueue` WHERE `executed` <= '%s'", dbesc(NULL_DATE));
-	return $s[0]["total"];
+	$s = q("SELECT COUNT(*) AS `total` FROM `workerqueue` WHERE `executed` <= '%s' AND NOT `done`", dbesc(NULL_DATE));
+	if (dbm::is_result($s)) {
+		return $s[0]["total"];
+	} else {
+		return 0;
+	}
 }
 
 /**
@@ -144,8 +161,12 @@ function poller_total_entries() {
  * @return integer Number of active poller processes
  */
 function poller_highest_priority() {
-	$s = q("SELECT `priority` FROM `workerqueue` WHERE `executed` <= '%s' ORDER BY `priority` LIMIT 1", dbesc(NULL_DATE));
-	return $s[0]["priority"];
+	$s = q("SELECT `priority` FROM `workerqueue` WHERE `executed` <= '%s' AND NOT `done` ORDER BY `priority` LIMIT 1", dbesc(NULL_DATE));
+	if (dbm::is_result($s)) {
+		return $s[0]["priority"];
+	} else {
+		return 0;
+	}
 }
 
 /**
@@ -156,7 +177,7 @@ function poller_highest_priority() {
  * @return integer Is there a process running with that priority?
  */
 function poller_process_with_priority_active($priority) {
-	$s = q("SELECT `id` FROM `workerqueue` WHERE `priority` <= %d AND `executed` > '%s' LIMIT 1",
+	$s = q("SELECT `id` FROM `workerqueue` WHERE `priority` <= %d AND `executed` > '%s' AND NOT `done` LIMIT 1",
 			intval($priority), dbesc(NULL_DATE));
 	return dbm::is_result($s);
 }
@@ -169,6 +190,7 @@ function poller_process_with_priority_active($priority) {
  * @return boolean "true" if further processing should be stopped
  */
 function poller_execute($queue) {
+	global $poller_db_duration, $poller_last_update;
 
 	$a = get_app();
 
@@ -208,10 +230,29 @@ function poller_execute($queue) {
 	$funcname = str_replace(".php", "", basename($argv[0]))."_run";
 
 	if (function_exists($funcname)) {
+
+		// We constantly update the "executed" date every minute to avoid being killed too soon
+		if (!isset($poller_last_update)) {
+			$poller_last_update = strtotime($queue["executed"]);
+		}
+
+		$age = (time() - $poller_last_update) / 60;
+		$poller_last_update = time();
+
+		if ($age > 1) {
+			$stamp = (float)microtime(true);
+			dba::update('workerqueue', array('executed' => datetime_convert()), array('pid' => $mypid, 'done' => false));
+			$poller_db_duration += (microtime(true) - $stamp);
+		}
+
 		poller_exec_function($queue, $funcname, $argv);
-		dba::delete('workerqueue', array('id' => $queue["id"]));
+
+		$stamp = (float)microtime(true);
+		dba::update('workerqueue', array('done' => true), array('id' => $queue["id"]));
+		$poller_db_duration = (microtime(true) - $stamp);
 	} else {
 		logger("Function ".$funcname." does not exist");
+		dba::delete('workerqueue', array('id' => $queue["id"]));
 	}
 
 	return true;
@@ -225,6 +266,7 @@ function poller_execute($queue) {
  * @param array $argv Array of values to be passed to the function
  */
 function poller_exec_function($queue, $funcname, $argv) {
+	global $poller_up_start, $poller_db_duration, $poller_lock_duration;
 
 	$a = get_app();
 
@@ -232,7 +274,9 @@ function poller_exec_function($queue, $funcname, $argv) {
 
 	$argc = count($argv);
 
-	logger("Process ".$mypid." - Prio ".$queue["priority"]." - ID ".$queue["id"].": ".$funcname." ".$queue["parameter"]);
+	$new_process_id = uniqid("wrk", true);
+
+	logger("Process ".$mypid." - Prio ".$queue["priority"]." - ID ".$queue["id"].": ".$funcname." ".$queue["parameter"]." - Process PID: ".$new_process_id);
 
 	$stamp = (float)microtime(true);
 
@@ -254,14 +298,34 @@ function poller_exec_function($queue, $funcname, $argv) {
 	// For better logging create a new process id for every worker call
 	// But preserve the old one for the worker
 	$old_process_id = $a->process_id;
-	$a->process_id = uniqid("wrk", true);
+	$a->process_id = $new_process_id;
+	$a->queue = $queue;
+
+	$up_duration = number_format(microtime(true) - $poller_up_start, 3);
+
+	// Reset global data to avoid interferences
+	unset($_SESSION);
 
 	$funcname($argv, $argc);
 
 	$a->process_id = $old_process_id;
+	unset($a->queue);
 
 	$duration = number_format(microtime(true) - $stamp, 3);
 
+	$poller_up_start = microtime(true);
+
+	/* With these values we can analyze how effective the worker is.
+	 * The database and rest time should be low since this is the unproductive time.
+	 * The execution time is the productive time.
+	 * By changing parameters like the maximum number of workers we can check the effectivness.
+	*/
+	logger('DB: '.number_format($poller_db_duration, 2).
+		' - Lock: '.number_format($poller_lock_duration, 2).
+		' - Rest: '.number_format($up_duration - $poller_db_duration - $poller_lock_duration, 2).
+		' - Execution: '.number_format($duration, 2), LOGGER_DEBUG);
+	$poller_lock_duration = 0;
+
 	if ($duration > 3600) {
 		logger("Prio ".$queue["priority"].": ".$queue["parameter"]." - longer than 1 hour (".round($duration/60, 3).")", LOGGER_DEBUG);
 	} elseif ($duration > 600) {
@@ -272,7 +336,7 @@ function poller_exec_function($queue, $funcname, $argv) {
 		logger("Prio ".$queue["priority"].": ".$queue["parameter"]." - longer than 2 minutes (".round($duration/60, 3).")", LOGGER_DEBUG);
 	}
 
-	logger("Process ".$mypid." - Prio ".$queue["priority"]." - ID ".$queue["id"].": ".$funcname." - done in ".$duration." seconds.");
+	logger("Process ".$mypid." - Prio ".$queue["priority"]." - ID ".$queue["id"].": ".$funcname." - done in ".$duration." seconds. Process PID: ".$new_process_id);
 
 	// Write down the performance values into the log
 	if (Config::get("system", "profiler")) {
@@ -414,46 +478,48 @@ function poller_max_connections_reached() {
  *
  */
 function poller_kill_stale_workers() {
-	$r = q("SELECT `pid`, `executed`, `priority`, `parameter` FROM `workerqueue` WHERE `executed` > '%s'", dbesc(NULL_DATE));
-
-	if (!dbm::is_result($r)) {
-		// No processing here needed
-		return;
-	}
-
-	foreach ($r AS $pid) {
-		if (!posix_kill($pid["pid"], 0)) {
+	$entries = dba::select('workerqueue', array('id', 'pid', 'executed', 'priority', 'parameter'),
+				array('`executed` > ? AND NOT `done` AND `pid` != 0', NULL_DATE),
+				array('order' => array('priority', 'created')));
+	while ($entry = dba::fetch($entries)) {
+		if (!posix_kill($entry["pid"], 0)) {
 			dba::update('workerqueue', array('executed' => NULL_DATE, 'pid' => 0),
-					array('pid' => $pid["pid"]));
+					array('id' => $entry["id"]));
 		} else {
 			// Kill long running processes
-
 			// Check if the priority is in a valid range
-			if (!in_array($pid["priority"], array(PRIORITY_CRITICAL, PRIORITY_HIGH, PRIORITY_MEDIUM, PRIORITY_LOW, PRIORITY_NEGLIGIBLE))) {
-				$pid["priority"] = PRIORITY_MEDIUM;
+			if (!in_array($entry["priority"], array(PRIORITY_CRITICAL, PRIORITY_HIGH, PRIORITY_MEDIUM, PRIORITY_LOW, PRIORITY_NEGLIGIBLE))) {
+				$entry["priority"] = PRIORITY_MEDIUM;
 			}
 
 			// Define the maximum durations
-			$max_duration_defaults = array(PRIORITY_CRITICAL => 360, PRIORITY_HIGH => 10, PRIORITY_MEDIUM => 60, PRIORITY_LOW => 180, PRIORITY_NEGLIGIBLE => 360);
-			$max_duration = $max_duration_defaults[$pid["priority"]];
+			$max_duration_defaults = array(PRIORITY_CRITICAL => 720, PRIORITY_HIGH => 10, PRIORITY_MEDIUM => 60, PRIORITY_LOW => 180, PRIORITY_NEGLIGIBLE => 720);
+			$max_duration = $max_duration_defaults[$entry["priority"]];
 
-			$argv = json_decode($pid["parameter"]);
+			$argv = json_decode($entry["parameter"]);
 			$argv[0] = basename($argv[0]);
 
 			// How long is the process already running?
-			$duration = (time() - strtotime($pid["executed"])) / 60;
+			$duration = (time() - strtotime($entry["executed"])) / 60;
 			if ($duration > $max_duration) {
-				logger("Worker process ".$pid["pid"]." (".implode(" ", $argv).") took more than ".$max_duration." minutes. It will be killed now.");
-				posix_kill($pid["pid"], SIGTERM);
+				logger("Worker process ".$entry["pid"]." (".implode(" ", $argv).") took more than ".$max_duration." minutes. It will be killed now.");
+				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.
+				// Additionally we are lowering the priority. (But not PRIORITY_CRITICAL)
+				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;
+				}
 				dba::update('workerqueue',
-						array('executed' => NULL_DATE, 'created' => datetime_convert(), 'priority' => PRIORITY_NEGLIGIBLE, 'pid' => 0),
-						array('pid' => $pid["pid"]));
+						array('executed' => NULL_DATE, 'created' => datetime_convert(), 'priority' => $new_priority, 'pid' => 0),
+						array('id' => $entry["id"]));
 			} else {
-				logger("Worker process ".$pid["pid"]." (".implode(" ", $argv).") now runs for ".round($duration)." of ".$max_duration." allowed minutes. That's okay.", LOGGER_DEBUG);
+				logger("Worker process ".$entry["pid"]." (".implode(" ", $argv).") now runs for ".round($duration)." of ".$max_duration." allowed minutes. That's okay.", LOGGER_DEBUG);
 			}
 		}
 	}
@@ -462,13 +528,9 @@ function poller_kill_stale_workers() {
 /**
  * @brief Checks if the number of active workers exceeds the given limits
  *
- * @param integer $entries The number of not executed entries in the worker queue
- * @param integer $top_priority The highest not executed priority in the worker queue
- * @param boolean $high_running Is a process with priority "$top_priority" running?
- *
  * @return bool Are there too much workers running?
  */
-function poller_too_much_workers($entries = NULL, $top_priority = NULL, $high_running = NULL) {
+function poller_too_much_workers() {
 	$queues = Config::get("system", "worker_queues", 4);
 
 	$maxqueues = $queues;
@@ -492,35 +554,43 @@ function poller_too_much_workers($entries = NULL, $top_priority = NULL, $high_ru
 			$listitem = array();
 
 			// Adding all processes with no workerqueue entry
-			$processes = dba::p("SELECT COUNT(*) AS `running` FROM `process` WHERE NOT EXISTS (SELECT id FROM `workerqueue` WHERE `workerqueue`.`pid` = `process`.`pid`)");
+			$processes = dba::p("SELECT COUNT(*) AS `running` FROM `process` WHERE NOT EXISTS
+						(SELECT id FROM `workerqueue`
+						WHERE `workerqueue`.`pid` = `process`.`pid` AND NOT `done` AND `pid` != ?)", getmypid());
 			if ($process = dba::fetch($processes)) {
 				$listitem[0] = "0:".$process["running"];
 			}
 			dba::close($processes);
 
 			// Now adding all processes with workerqueue entries
-			$entries = dba::p("SELECT COUNT(*) AS `entries`, `priority` FROM `workerqueue` GROUP BY `priority`");
+			$entries = dba::p("SELECT COUNT(*) AS `entries`, `priority` FROM `workerqueue` WHERE NOT `done` GROUP BY `priority`");
 			while ($entry = dba::fetch($entries)) {
-				$processes = dba::p("SELECT COUNT(*) AS `running` FROM `process` INNER JOIN `workerqueue` ON `workerqueue`.`pid` = `process`.`pid` WHERE `priority` = ?", $entry["priority"]);
+				$processes = dba::p("SELECT COUNT(*) AS `running` FROM `process` INNER JOIN `workerqueue` ON `workerqueue`.`pid` = `process`.`pid` AND NOT `done` WHERE `priority` = ?", $entry["priority"]);
 				if ($process = dba::fetch($processes)) {
 					$listitem[$entry["priority"]] = $entry["priority"].":".$process["running"]."/".$entry["entries"];
 				}
 				dba::close($processes);
 			}
 			dba::close($entries);
-			$processlist = ' ('.implode(', ', $listitem).')';
-		}
 
-		if (is_null($entries)) {
-			$entries = poller_total_entries();
+			$intervals = array(1, 10, 60);
+			$jobs_per_minute = array();
+			foreach ($intervals AS $interval) {
+				$jobs = dba::p("SELECT COUNT(*) AS `jobs` FROM `workerqueue` WHERE `done` AND `executed` > UTC_TIMESTAMP() - INTERVAL ".intval($interval)." MINUTE");
+				if ($job = dba::fetch($jobs)) {
+					$jobs_per_minute[$interval] = number_format($job['jobs'] / $interval, 0);
+				}
+				dba::close($jobs);
+			}
+			$processlist = ' - jpm: '.implode('/', $jobs_per_minute).' ('.implode(', ', $listitem).')';
 		}
+
+		$entries = poller_total_entries();
+
 		if (Config::get("system", "worker_fastlane", false) && ($queues > 0) && ($entries > 0) && ($active >= $queues)) {
-			if (is_null($top_priority)) {
-				$top_priority = poller_highest_priority();
-			}
-			if (is_null($high_running)) {
-				$high_running = poller_process_with_priority_active($top_priority);
-			}
+			$top_priority = poller_highest_priority();
+			$high_running = poller_process_with_priority_active($top_priority);
+
 			if (!$high_running && ($top_priority > PRIORITY_UNDEFINED) && ($top_priority < PRIORITY_NEGLIGIBLE)) {
 				logger("There are jobs with priority ".$top_priority." waiting but none is executed. Open a fastlane.", LOGGER_DEBUG);
 				$queues = $active + 1;
@@ -533,8 +603,7 @@ function poller_too_much_workers($entries = NULL, $top_priority = NULL, $high_ru
 		if (!Config::get("system", "worker_dont_fork") && ($queues > ($active + 1)) && ($entries > 1)) {
 			logger("Active workers: ".$active."/".$queues." Fork a new worker.", LOGGER_DEBUG);
 			$args = array("include/poller.php", "no_cron");
-			$a = get_app();
-			$a->proc_run($args);
+			get_app()->proc_run($args);
 		}
 	}
 
@@ -567,7 +636,7 @@ function poller_passing_slow(&$highest_priority) {
 
 	$r = q("SELECT `priority`
 		FROM `process`
-		INNER JOIN `workerqueue` ON `workerqueue`.`pid` = `process`.`pid`");
+		INNER JOIN `workerqueue` ON `workerqueue`.`pid` = `process`.`pid` AND NOT `done`");
 
 	// No active processes at all? Fine
 	if (!dbm::is_result($r)) {
@@ -604,87 +673,117 @@ function poller_passing_slow(&$highest_priority) {
 }
 
 /**
- * @brief Returns the next worker process
+ * @brief Find and claim the next worker process for us
  *
- * @return string SQL statement
+ * @param boolean $passing_slow Returns if we had passed low priority processes
+ * @return boolean Have we found something?
  */
-function poller_worker_process() {
+function find_worker_processes(&$passing_slow) {
+
+	$mypid = getmypid();
 
 	// Check if we should pass some low priority process
 	$highest_priority = 0;
+	$found = false;
+	$passing_slow = false;
 
-	if (poller_passing_slow($highest_priority)) {
-		dba::lock('workerqueue');
+	// The higher the number of parallel workers, the more we prefetch to prevent concurring access
+	// We decrease the limit with the number of entries left in the queue
+	$worker_queues = Config::get("system", "worker_queues", 4);
+	$queue_length = Config::get('system', 'worker_fetch_limit', $worker_queues);
+	$lower_job_limit = $worker_queues * $queue_length * 2;
+	$jobs = poller_total_entries();
+
+	// Now do some magic
+	$exponent = 2;
+	$slope = $queue_length / pow($lower_job_limit, $exponent);
+	$limit = min($queue_length, ceil($slope * pow($jobs, $exponent)));
 
+	logger('Total: '.$jobs.' - Maximum: '.$queue_length.' - jobs per queue: '.$limit, LOGGER_DEBUG);
+
+	if (poller_passing_slow($highest_priority)) {
 		// Are there waiting processes with a higher priority than the currently highest?
-		$r = q("SELECT * FROM `workerqueue`
-				WHERE `executed` <= '%s' AND `priority` < %d
-				ORDER BY `priority`, `created` LIMIT 1",
-				dbesc(NULL_DATE),
-				intval($highest_priority));
-		if (dbm::is_result($r)) {
-			return $r;
+		$result = dba::select('workerqueue', array('id'), array("`executed` <= ? AND `priority` < ? AND NOT `done`", NULL_DATE, $highest_priority),
+				array('limit' => $limit, 'order' => array('priority', 'created'), 'only_query' => true));
+
+		while ($id = dba::fetch($result)) {
+			$ids[] = $id["id"];
 		}
-		// Give slower processes some processing time
-		$r = q("SELECT * FROM `workerqueue`
-				WHERE `executed` <= '%s' AND `priority` > %d
-				ORDER BY `priority`, `created` LIMIT 1",
-				dbesc(NULL_DATE),
-				intval($highest_priority));
+		dba::close($result);
 
-		if (dbm::is_result($r)) {
-			return $r;
+		$found = (count($ids) > 0);
+
+		if (!$found) {
+			// Give slower processes some processing time
+			$result = dba::select('workerqueue', array('id'), array("`executed` <= ? AND `priority` > ? AND NOT `done`", NULL_DATE, $highest_priority),
+					array('limit' => $limit, 'order' => array('priority', 'created'), 'only_query' => true));
+
+			while ($id = dba::fetch($result)) {
+				$ids[] = $id["id"];
+			}
+			dba::close($result);
+
+			$found = (count($ids) > 0);
+			$passing_slow = $found;
 		}
-	} else {
-		dba::lock('workerqueue');
 	}
 
 	// If there is no result (or we shouldn't pass lower processes) we check without priority limit
-	if (!dbm::is_result($r)) {
-		$r = q("SELECT * FROM `workerqueue` WHERE `executed` <= '%s' ORDER BY `priority`, `created` LIMIT 1", dbesc(NULL_DATE));
+	if (!$found) {
+		$result = dba::select('workerqueue', array('id'), array("`executed` <= ? AND NOT `done`", NULL_DATE),
+				array('limit' => $limit, 'order' => array('priority', 'created'), 'only_query' => true));
+
+		while ($id = dba::fetch($result)) {
+			$ids[] = $id["id"];
+		}
+		dba::close($result);
+
+		$found = (count($ids) > 0);
 	}
 
-	// We only unlock the tables here, when we got no data
-	if (!dbm::is_result($r)) {
-		dba::unlock();
+	if ($found) {
+		$condition = "`id` IN (".substr(str_repeat("?, ", count($ids)), 0, -2).") AND `pid` = 0 AND NOT `done`";
+		array_unshift($ids, $condition);
+		dba::update('workerqueue', array('executed' => datetime_convert(), 'pid' => $mypid), $ids);
 	}
 
-	return $r;
+	return $found;
 }
 
 /**
- * @brief Assigns a workerqueue entry to the current process
- *
- * When we are sure that the table locks are working correctly, we can remove the checks from here
- *
- * @param array $queue Workerqueue entry
+ * @brief Returns the next worker process
  *
- * @return boolean "true" if the claiming was successful
+ * @param boolean $passing_slow Returns if we had passed low priority processes
+ * @return string SQL statement
  */
-function poller_claim_process($queue) {
-	$mypid = getmypid();
+function poller_worker_process(&$passing_slow) {
+	global $poller_db_duration, $poller_lock_duration;
 
-	$success = dba::update('workerqueue', array('executed' => datetime_convert(), 'pid' => $mypid),
-			array('id' => $queue["id"], 'pid' => 0));
+	$stamp = (float)microtime(true);
 
-	if (!$success) {
-		logger("Couldn't update queue entry ".$queue["id"]." - skip this execution", LOGGER_DEBUG);
-		return false;
+	// There can already be jobs for us in the queue.
+	$r = q("SELECT * FROM `workerqueue` WHERE `pid` = %d AND NOT `done`", intval(getmypid()));
+	if (dbm::is_result($r)) {
+		$poller_db_duration += (microtime(true) - $stamp);
+		return $r;
 	}
 
-	// Assure that there are no tasks executed twice
-	$id = q("SELECT `pid`, `executed` FROM `workerqueue` WHERE `id` = %d", intval($queue["id"]));
-	if (!$id) {
-		logger("Queue item ".$queue["id"]." vanished - skip this execution", LOGGER_DEBUG);
-		return false;
-	} elseif ((strtotime($id[0]["executed"]) <= 0) || ($id[0]["pid"] == 0)) {
-		logger("Entry for queue item ".$queue["id"]." wasn't stored - skip this execution", LOGGER_DEBUG);
-		return false;
-	} elseif ($id[0]["pid"] != $mypid) {
-		logger("Queue item ".$queue["id"]." is to be executed by process ".$id[0]["pid"]." and not by me (".$mypid.") - skip this execution", LOGGER_DEBUG);
+	$stamp = (float)microtime(true);
+	if (!Lock::set('poller_worker_process')) {
 		return false;
 	}
-	return true;
+	$poller_lock_duration = (microtime(true) - $stamp);
+
+	$stamp = (float)microtime(true);
+	$found = find_worker_processes($passing_slow);
+	$poller_db_duration += (microtime(true) - $stamp);
+
+	Lock::remove('poller_worker_process');
+
+	if ($found) {
+		$r = q("SELECT * FROM `workerqueue` WHERE `pid` = %d AND NOT `done`", intval(getmypid()));
+	}
+	return $r;
 }
 
 /**
@@ -693,7 +792,7 @@ function poller_claim_process($queue) {
 function poller_unclaim_process() {
 	$mypid = getmypid();
 
-	dba::update('workerqueue', array('executed' => NULL_DATE, 'pid' => 0), array('pid' => $mypid));
+	dba::update('workerqueue', array('executed' => NULL_DATE, 'pid' => 0), array('pid' => $mypid, 'done' => false));
 }
 
 /**
@@ -704,7 +803,7 @@ function call_worker() {
 		return;
 	}
 
-	$url = App::get_baseurl()."/worker";
+	$url = System::baseUrl()."/worker";
 	fetch_url($url, false, $redirects, 1);
 }
 
@@ -740,8 +839,7 @@ function call_worker_if_idle() {
 		logger('Call poller', LOGGER_DEBUG);
 
 		$args = array("include/poller.php", "no_cron");
-		$a = get_app();
-		$a->proc_run($args);
+		get_app()->proc_run($args);
 		return;
 	}
 
@@ -796,7 +894,5 @@ if (array_search(__file__,get_included_files())===0){
 
 	get_app()->end_process();
 
-	Lock::remove('poller_worker');
-
 	killme();
 }