<?php if (!file_exists("boot.php") AND (sizeof($_SERVER["argv"]) != 0)) { $directory = dirname($_SERVER["argv"][0]); if (substr($directory, 0, 1) != "/") $directory = $_SERVER["PWD"]."/".$directory; $directory = realpath($directory."/.."); chdir($directory); } require_once("boot.php"); function poller_run(&$argv, &$argc){ global $a, $db; if(is_null($a)) { $a = new App; } if(is_null($db)) { @include(".htconfig.php"); require_once("include/dba.php"); $db = new dba($db_host, $db_user, $db_pass, $db_data); unset($db_host, $db_user, $db_pass, $db_data); }; if (poller_max_connections_reached()) return; if (App::maxload_reached()) return; // Checking the number of workers if (poller_too_much_workers(1)) { poller_kill_stale_workers(); return; } if(($argc <= 1) OR ($argv[1] != "no_cron")) { // Run the cron job that calls all other jobs proc_run("php","include/cron.php"); // Run the cronhooks job separately from cron for being able to use a different timing proc_run("php","include/cronhooks.php"); // Cleaning dead processes poller_kill_stale_workers(); } else // Sleep four seconds before checking for running processes again to avoid having too many workers sleep(4); // Checking number of workers if (poller_too_much_workers(2)) return; $starttime = time(); while ($r = q("SELECT * FROM `workerqueue` WHERE `executed` = '0000-00-00 00:00:00' ORDER BY `created` LIMIT 1")) { // Constantly check the number of available database connections to let the frontend be accessible at any time if (poller_max_connections_reached()) return; // Count active workers and compare them with a maximum value that depends on the load if (poller_too_much_workers(3)) return; q("UPDATE `workerqueue` SET `executed` = '%s', `pid` = %d WHERE `id` = %d AND `executed` = '0000-00-00 00:00:00'", dbesc(datetime_convert()), intval(getmypid()), intval($r[0]["id"])); // Assure that there are no tasks executed twice $id = q("SELECT `id` FROM `workerqueue` WHERE `id` = %d AND `pid` = %d", intval($r[0]["id"]), intval(getmypid())); if (!$id) { logger("Queue item ".$r[0]["id"]." was executed multiple times - skip this execution", LOGGER_DEBUG); continue; } $argv = json_decode($r[0]["parameter"]); $argc = count($argv); // Check for existance and validity of the include file $include = $argv[0]; if (!validate_include($include)) { logger("Include file ".$argv[0]." is not valid!"); q("DELETE FROM `workerqueue` WHERE `id` = %d", intval($r[0]["id"])); continue; } require_once($include); $funcname=str_replace(".php", "", basename($argv[0]))."_run"; if (function_exists($funcname)) { logger("Process ".getmypid()." - ID ".$r[0]["id"].": ".$funcname." ".$r[0]["parameter"]); $funcname($argv, $argc); logger("Process ".getmypid()." - ID ".$r[0]["id"].": ".$funcname." - done"); q("DELETE FROM `workerqueue` WHERE `id` = %d", intval($r[0]["id"])); } else logger("Function ".$funcname." does not exist"); // Quit the poller once every hour if (time() > ($starttime + 3600)) return; } } /** * @brief Checks if the number of database connections has reached a critical limit. * * @return bool Are more than 3/4 of the maximum connections used? */ function poller_max_connections_reached() { // Fetch the max value from the config. This is needed when the system cannot detect the correct value by itself. $max = get_config("system", "max_connections"); // Fetch the percentage level where the poller will get active $maxlevel = get_config("system", "max_connections_level"); if ($maxlevel == 0) $maxlevel = 75; if ($max == 0) { // the maximum number of possible user connections can be a system variable $r = q("SHOW VARIABLES WHERE `variable_name` = 'max_user_connections'"); if ($r) $max = $r[0]["Value"]; // Or it can be granted. This overrides the system variable $r = q("SHOW GRANTS"); if ($r) foreach ($r AS $grants) { $grant = array_pop($grants); if (stristr($grant, "GRANT USAGE ON")) if (preg_match("/WITH MAX_USER_CONNECTIONS (\d*)/", $grant, $match)) $max = $match[1]; } } // If $max is set we will use the processlist to determine the current number of connections // The processlist only shows entries of the current user if ($max != 0) { $r = q("SHOW PROCESSLIST"); if (!$r) return false; $used = count($r); logger("Connection usage (user values): ".$used."/".$max, LOGGER_DEBUG); $level = ($used / $max) * 100; if ($level >= $maxlevel) { logger("Maximum level (".$maxlevel."%) of user connections reached: ".$used."/".$max); return true; } } // We will now check for the system values. // This limit could be reached although the user limits are fine. $r = q("SHOW VARIABLES WHERE `variable_name` = 'max_connections'"); if (!$r) return false; $max = intval($r[0]["Value"]); if ($max == 0) return false; $r = q("SHOW STATUS WHERE `variable_name` = 'Threads_connected'"); if (!$r) return false; $used = intval($r[0]["Value"]); if ($used == 0) return false; logger("Connection usage (system values): ".$used."/".$max, LOGGER_DEBUG); $level = $used / $max * 100; if ($level < $maxlevel) return false; logger("Maximum level (".$level."%) of system connections reached: ".$used."/".$max); return true; } /** * @brief fix the queue entry if the worker process died * */ function poller_kill_stale_workers() { $r = q("SELECT `pid`, `executed` FROM `workerqueue` WHERE `executed` != '0000-00-00 00:00:00'"); if (!is_array($r) || count($r) == 0) { // No processing here needed return; } foreach($r AS $pid) if (!posix_kill($pid["pid"], 0)) q("UPDATE `workerqueue` SET `executed` = '0000-00-00 00:00:00', `pid` = 0 WHERE `pid` = %d", intval($pid["pid"])); else { // Kill long running processes $duration = (time() - strtotime($pid["executed"])) / 60; if ($duration > 180) { logger("Worker process ".$pid["pid"]." took more than 3 hours. It will be killed now."); posix_kill($pid["pid"], SIGTERM); // Question: If a process is stale: Should we remove it or should we reschedule it? // By now we rescheduling it. It's maybe not the wisest decision? q("UPDATE `workerqueue` SET `executed` = '0000-00-00 00:00:00', `pid` = 0 WHERE `pid` = %d", intval($pid["pid"])); } else logger("Worker process ".$pid["pid"]." now runs for ".round($duration)." minutes. That's okay.", LOGGER_DEBUG); } } function poller_too_much_workers($stage) { $queues = get_config("system", "worker_queues"); if ($queues == 0) $queues = 4; $active = poller_active_workers(); // Decrease the number of workers at higher load $load = current_load(); if($load) { $maxsysload = intval(get_config('system','maxloadavg')); if($maxsysload < 1) $maxsysload = 50; $maxworkers = $queues; // Some magical mathemathics to reduce the workers $exponent = 3; $slope = $maxworkers / pow($maxsysload, $exponent); $queues = ceil($slope * pow(max(0, $maxsysload - $load), $exponent)); logger("Current load stage ".$stage.": ".$load." - maximum: ".$maxsysload." - current queues: ".$active." - maximum: ".$queues, LOGGER_DEBUG); } return($active >= $queues); } function poller_active_workers() { $workers = q("SELECT COUNT(*) AS `workers` FROM `workerqueue` WHERE `executed` != '0000-00-00 00:00:00'"); return($workers[0]["workers"]); } if (array_search(__file__,get_included_files())===0){ poller_run($_SERVER["argv"],$_SERVER["argc"]); killme(); } ?>