src/Core/Worker.php

   1 <?php
   2 /**
   3  * @copyright Copyright (C) 2020, Friendica
   4  *
   5  * @license GNU AGPL version 3 or any later version
   6  *
   7  * This program is free software: you can redistribute it and/or modify
   8  * it under the terms of the GNU Affero General Public License as
   9  * published by the Free Software Foundation, either version 3 of the
  10  * License, or (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU Affero General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Affero General Public License
  18  * along with this program.  If not, see <https://www.gnu.org/licenses/>.
  19  *
  20  */
  21
  22 namespace Friendica\Core;
  23
  24 use Friendica\Core;
  25 use Friendica\Core\Process as ProcessAlias;
  26 use Friendica\Database\DBA;
  27 use Friendica\DI;
  28 use Friendica\Model\Process;
  29 use Friendica\Util\DateTimeFormat;
  30
  31 /**
  32  * Contains the class for the worker background job processing
  33  */
  34 class Worker
  35 {
  36         const STATE_STARTUP    = 1; // Worker is in startup. This takes most time.
  37         const STATE_LONG_LOOP  = 2; // Worker is processing the whole - long - loop.
  38         const STATE_REFETCH    = 3; // Worker had refetched jobs in the execution loop.
  39         const STATE_SHORT_LOOP = 4; // Worker is processing preassigned jobs, thus saving much time.
  40
  41         const FAST_COMMANDS = ['APDelivery', 'Delivery', 'CreateShadowEntry'];
  42
  43         const LOCK_PROCESS = 'worker_process';
  44         const LOCK_WORKER = 'worker';
  45
  46         private static $up_start;
  47         private static $db_duration = 0;
  48         private static $db_duration_count = 0;
  49         private static $db_duration_write = 0;
  50         private static $db_duration_stat = 0;
  51         private static $lock_duration = 0;
  52         private static $last_update;
  53         private static $state;
  54
  55         /**
  56          * Processes the tasks that are in the workerqueue table
  57          *
  58          * @param boolean $run_cron Should the cron processes be executed?
  59          * @return void
  60          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
  61          */
  62         public static function processQueue($run_cron = true)
  63         {
  64                 // Ensure that all "strtotime" operations do run timezone independent
  65                 date_default_timezone_set('UTC');
  66
  67                 self::$up_start = microtime(true);
  68
  69                 // At first check the maximum load. We shouldn't continue with a high load
  70                 if (DI::process()->isMaxLoadReached()) {
  71                         Logger::notice('Pre check: maximum load reached, quitting.');
  72                         return;
  73                 }
  74
  75                 // We now start the process. This is done after the load check since this could increase the load.
  76                 DI::process()->start();
  77
  78                 // Kill stale processes every 5 minutes
  79                 $last_cleanup = DI::config()->get('system', 'worker_last_cleaned', 0);
  80                 if (time() > ($last_cleanup + 300)) {
  81                         DI::config()->set('system', 'worker_last_cleaned', time());
  82                         self::killStaleWorkers();
  83                 }
  84
  85                 // Check if the system is ready
  86                 if (!self::isReady()) {
  87                         return;
  88                 }
  89
  90                 // Now we start additional cron processes if we should do so
  91                 if ($run_cron) {
  92                         self::runCron();
  93                 }
  94
  95                 $last_check = $starttime = time();
  96                 self::$state = self::STATE_STARTUP;
  97
  98                 // We fetch the next queue entry that is about to be executed
  99                 while ($r = self::workerProcess()) {
 100                         // Don't refetch when a worker fetches tasks for multiple workers
 101                         $refetched = DI::config()->get('system', 'worker_multiple_fetch');
 102                         foreach ($r as $entry) {
 103                                 // Assure that the priority is an integer value
 104                                 $entry['priority'] = (int)$entry['priority'];
 105
 106                                 // The work will be done
 107                                 if (!self::execute($entry)) {
 108                                         Logger::info('Process execution failed, quitting.');
 109                                         return;
 110                                 }
 111
 112                                 // Trying to fetch new processes - but only once when successful
 113                                 if (!$refetched && DI::lock()->acquire(self::LOCK_PROCESS, 0)) {
 114                                         self::findWorkerProcesses();
 115                                         DI::lock()->release(self::LOCK_PROCESS);
 116                                         self::$state = self::STATE_REFETCH;
 117                                         $refetched = true;
 118                                 } else {
 119                                         self::$state = self::STATE_SHORT_LOOP;
 120                                 }
 121                         }
 122
 123                         // To avoid the quitting of multiple workers only one worker at a time will execute the check
 124                         if ((time() > $last_check + 5) && !self::getWaitingJobForPID()) {
 125                                 self::$state = self::STATE_LONG_LOOP;
 126
 127                                 if (DI::lock()->acquire(self::LOCK_WORKER, 0)) {
 128                                 // Count active workers and compare them with a maximum value that depends on the load
 129                                         if (self::tooMuchWorkers()) {
 130                                                 Logger::info('Active worker limit reached, quitting.');
 131                                                 DI::lock()->release(self::LOCK_WORKER);
 132                                                 return;
 133                                         }
 134
 135                                         // Check free memory
 136                                         if (DI::process()->isMinMemoryReached()) {
 137                                                 Logger::notice('Memory limit reached, quitting.');
 138                                                 DI::lock()->release(self::LOCK_WORKER);
 139                                                 return;
 140                                         }
 141                                         DI::lock()->release(self::LOCK_WORKER);
 142                                 }
 143                                 $last_check = time();
 144                         }
 145
 146                         // Quit the worker once every cron interval
 147                         if (time() > ($starttime + (DI::config()->get('system', 'cron_interval') * 60))) {
 148                                 Logger::info('Process lifetime reached, respawning.');
 149                                 self::unclaimProcess();
 150                                 self::spawnWorker();
 151                                 return;
 152                         }
 153                 }
 154
 155                 // Cleaning up. Possibly not needed, but it doesn't harm anything.
 156                 if (DI::config()->get('system', 'worker_daemon_mode', false)) {
 157                         self::IPCSetJobState(false);
 158                 }
 159                 Logger::info("Couldn't select a workerqueue entry, quitting process", ['pid' => getmypid()]);
 160         }
 161
 162         /**
 163          * Checks if the system is ready.
 164          *
 165          * Several system parameters like memory, connections and processes are checked.
 166          *
 167          * @return boolean
 168          */
 169         public static function isReady()
 170         {
 171                 // Count active workers and compare them with a maximum value that depends on the load
 172                 if (self::tooMuchWorkers()) {
 173                         Logger::info('Active worker limit reached, quitting.');
 174                         return false;
 175                 }
 176
 177                 // Do we have too few memory?
 178                 if (DI::process()->isMinMemoryReached()) {
 179                         Logger::notice('Memory limit reached, quitting.');
 180                         return false;
 181                 }
 182
 183                 // Possibly there are too much database connections
 184                 if (self::maxConnectionsReached()) {
 185                         Logger::notice('Maximum connections reached, quitting.');
 186                         return false;
 187                 }
 188
 189                 // Possibly there are too much database processes that block the system
 190                 if (DI::process()->isMaxProcessesReached()) {
 191                         Logger::notice('Maximum processes reached, quitting.');
 192                         return false;
 193                 }
 194
 195                 return true;
 196         }
 197
 198         /**
 199          * Check if non executed tasks do exist in the worker queue
 200          *
 201          * @return boolean Returns "true" if tasks are existing
 202          * @throws \Exception
 203          */
 204         public static function entriesExists()
 205         {
 206                 $stamp = (float)microtime(true);
 207                 $exists = DBA::exists('workerqueue', ["NOT `done` AND `pid` = 0 AND `next_try` < ?", DateTimeFormat::utcNow()]);
 208                 self::$db_duration += (microtime(true) - $stamp);
 209                 return $exists;
 210         }
 211
 212         /**
 213          * Returns the number of deferred entries in the worker queue
 214          *
 215          * @return integer Number of deferred entries in the worker queue
 216          * @throws \Exception
 217          */
 218         private static function deferredEntries()
 219         {
 220                 $stamp = (float)microtime(true);
 221                 $count = DBA::count('workerqueue', ["NOT `done` AND `pid` = 0 AND `retrial` > ?", 0]);
 222                 self::$db_duration += (microtime(true) - $stamp);
 223                 self::$db_duration_count += (microtime(true) - $stamp);
 224                 return $count;
 225         }
 226
 227         /**
 228          * Returns the number of non executed entries in the worker queue
 229          *
 230          * @return integer Number of non executed entries in the worker queue
 231          * @throws \Exception
 232          */
 233         private static function totalEntries()
 234         {
 235                 $stamp = (float)microtime(true);
 236                 $count = DBA::count('workerqueue', ['done' => false, 'pid' => 0]);
 237                 self::$db_duration += (microtime(true) - $stamp);
 238                 self::$db_duration_count += (microtime(true) - $stamp);
 239                 return $count;
 240         }
 241
 242         /**
 243          * Returns the highest priority in the worker queue that isn't executed
 244          *
 245          * @return integer Number of active worker processes
 246          * @throws \Exception
 247          */
 248         private static function highestPriority()
 249         {
 250                 $stamp = (float)microtime(true);
 251                 $condition = ["`pid` = 0 AND NOT `done` AND `next_try` < ?", DateTimeFormat::utcNow()];
 252                 $workerqueue = DBA::selectFirst('workerqueue', ['priority'], $condition, ['order' => ['priority']]);
 253                 self::$db_duration += (microtime(true) - $stamp);
 254                 if (DBA::isResult($workerqueue)) {
 255                         return $workerqueue["priority"];
 256                 } else {
 257                         return 0;
 258                 }
 259         }
 260
 261         /**
 262          * Returns if a process with the given priority is running
 263          *
 264          * @param integer $priority The priority that should be checked
 265          *
 266          * @return integer Is there a process running with that priority?
 267          * @throws \Exception
 268          */
 269         private static function processWithPriorityActive($priority)
 270         {
 271                 $condition = ["`priority` <= ? AND `pid` != 0 AND NOT `done`", $priority];
 272                 return DBA::exists('workerqueue', $condition);
 273         }
 274
 275         /**
 276          * Execute a worker entry
 277          *
 278          * @param array $queue Workerqueue entry
 279          *
 280          * @return boolean "true" if further processing should be stopped
 281          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 282          */
 283         public static function execute($queue)
 284         {
 285                 $mypid = getmypid();
 286
 287                 // Quit when in maintenance
 288                 if (DI::config()->get('system', 'maintenance', false, true)) {
 289                         Logger::notice("Maintenance mode - quit process", ['pid' => $mypid]);
 290                         return false;
 291                 }
 292
 293                 // Constantly check the number of parallel database processes
 294                 if (DI::process()->isMaxProcessesReached()) {
 295                         Logger::notice("Max processes reached for process", ['pid' => $mypid]);
 296                         return false;
 297                 }
 298
 299                 // Constantly check the number of available database connections to let the frontend be accessible at any time
 300                 if (self::maxConnectionsReached()) {
 301                         Logger::notice("Max connection reached for process", ['pid' => $mypid]);
 302                         return false;
 303                 }
 304
 305                 $argv = json_decode($queue["parameter"], true);
 306                 if (empty($argv)) {
 307                         Logger::warning('Parameter is empty', ['queue' => $queue]);
 308                         return false;
 309                 }
 310
 311                 // Check for existance and validity of the include file
 312                 $include = $argv[0];
 313
 314                 if (method_exists(sprintf('Friendica\Worker\%s', $include), 'execute')) {
 315                         // We constantly update the "executed" date every minute to avoid being killed too soon
 316                         if (!isset(self::$last_update)) {
 317                                 self::$last_update = strtotime($queue["executed"]);
 318                         }
 319
 320                         $age = (time() - self::$last_update) / 60;
 321                         self::$last_update = time();
 322
 323                         if ($age > 1) {
 324                                 $stamp = (float)microtime(true);
 325                                 DBA::update('workerqueue', ['executed' => DateTimeFormat::utcNow()], ['pid' => $mypid, 'done' => false]);
 326                                 self::$db_duration += (microtime(true) - $stamp);
 327                                 self::$db_duration_write += (microtime(true) - $stamp);
 328                         }
 329
 330                         array_shift($argv);
 331
 332                         self::execFunction($queue, $include, $argv, true);
 333
 334                         $stamp = (float)microtime(true);
 335                         $condition = ["`id` = ? AND `next_try` < ?", $queue['id'], DateTimeFormat::utcNow()];
 336                         if (DBA::update('workerqueue', ['done' => true], $condition)) {
 337                                 DI::config()->set('system', 'last_worker_execution', DateTimeFormat::utcNow());
 338                         }
 339                         self::$db_duration = (microtime(true) - $stamp);
 340                         self::$db_duration_write += (microtime(true) - $stamp);
 341
 342                         return true;
 343                 }
 344
 345                 // The script could be provided as full path or only with the function name
 346                 if ($include == basename($include)) {
 347                         $include = "include/".$include.".php";
 348                 }
 349
 350                 if (!validate_include($include)) {
 351                         Logger::warning("Include file is not valid", ['file' => $argv[0]]);
 352                         $stamp = (float)microtime(true);
 353                         DBA::delete('workerqueue', ['id' => $queue["id"]]);
 354                         self::$db_duration = (microtime(true) - $stamp);
 355                         self::$db_duration_write += (microtime(true) - $stamp);
 356                         return true;
 357                 }
 358
 359                 require_once $include;
 360
 361                 $funcname = str_replace(".php", "", basename($argv[0]))."_run";
 362
 363                 if (function_exists($funcname)) {
 364                         // We constantly update the "executed" date every minute to avoid being killed too soon
 365                         if (!isset(self::$last_update)) {
 366                                 self::$last_update = strtotime($queue["executed"]);
 367                         }
 368
 369                         $age = (time() - self::$last_update) / 60;
 370                         self::$last_update = time();
 371
 372                         if ($age > 1) {
 373                                 $stamp = (float)microtime(true);
 374                                 DBA::update('workerqueue', ['executed' => DateTimeFormat::utcNow()], ['pid' => $mypid, 'done' => false]);
 375                                 self::$db_duration += (microtime(true) - $stamp);
 376                                 self::$db_duration_write += (microtime(true) - $stamp);
 377                         }
 378
 379                         self::execFunction($queue, $funcname, $argv, false);
 380
 381                         $stamp = (float)microtime(true);
 382                         if (DBA::update('workerqueue', ['done' => true], ['id' => $queue["id"]])) {
 383                                 DI::config()->set('system', 'last_worker_execution', DateTimeFormat::utcNow());
 384                         }
 385                         self::$db_duration = (microtime(true) - $stamp);
 386                         self::$db_duration_write += (microtime(true) - $stamp);
 387                 } else {
 388                         Logger::warning("Function does not exist", ['function' => $funcname]);
 389                         $stamp = (float)microtime(true);
 390                         DBA::delete('workerqueue', ['id' => $queue["id"]]);
 391                         self::$db_duration = (microtime(true) - $stamp);
 392                         self::$db_duration_write += (microtime(true) - $stamp);
 393                 }
 394
 395                 return true;
 396         }
 397
 398         /**
 399          * Execute a function from the queue
 400          *
 401          * @param array   $queue       Workerqueue entry
 402          * @param string  $funcname    name of the function
 403          * @param array   $argv        Array of values to be passed to the function
 404          * @param boolean $method_call boolean
 405          * @return void
 406          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 407          */
 408         private static function execFunction($queue, $funcname, $argv, $method_call)
 409         {
 410                 $a = DI::app();
 411
 412                 Logger::enableWorker($funcname);
 413
 414                 Logger::info("Process start.", ['priority' => $queue["priority"], 'id' => $queue["id"]]);
 415
 416                 $stamp = (float)microtime(true);
 417
 418                 // We use the callstack here to analyze the performance of executed worker entries.
 419                 // For this reason the variables have to be initialized.
 420                 DI::profiler()->reset();
 421
 422                 $a->queue = $queue;
 423
 424                 $up_duration = microtime(true) - self::$up_start;
 425
 426                 // Reset global data to avoid interferences
 427                 unset($_SESSION);
 428
 429                 // Set the workerLogger as new default logger
 430                 if ($method_call) {
 431                         call_user_func_array(sprintf('Friendica\Worker\%s::execute', $funcname), $argv);
 432                 } else {
 433                         $funcname($argv, count($argv));
 434                 }
 435
 436                 Logger::disableWorker();
 437
 438                 unset($a->queue);
 439
 440                 $duration = (microtime(true) - $stamp);
 441
 442                 /* With these values we can analyze how effective the worker is.
 443                  * The database and rest time should be low since this is the unproductive time.
 444                  * The execution time is the productive time.
 445                  * By changing parameters like the maximum number of workers we can check the effectivness.
 446                 */
 447                 $dbtotal = round(self::$db_duration, 2);
 448                 $dbread  = round(self::$db_duration - (self::$db_duration_count + self::$db_duration_write + self::$db_duration_stat), 2);
 449                 $dbcount = round(self::$db_duration_count, 2);
 450                 $dbstat  = round(self::$db_duration_stat, 2);
 451                 $dbwrite = round(self::$db_duration_write, 2);
 452                 $dblock  = round(self::$lock_duration, 2);
 453                 $rest    = round(max(0, $up_duration - (self::$db_duration + self::$lock_duration)), 2);
 454                 $exec    = round($duration, 2);
 455
 456                 Logger::info('Performance:', ['state' => self::$state, 'count' => $dbcount, 'stat' => $dbstat, 'write' => $dbwrite, 'lock' => $dblock, 'total' => $dbtotal, 'rest' => $rest, 'exec' => $exec]);
 457
 458                 self::$up_start = microtime(true);
 459                 self::$db_duration = 0;
 460                 self::$db_duration_count = 0;
 461                 self::$db_duration_stat = 0;
 462                 self::$db_duration_write = 0;
 463                 self::$lock_duration = 0;
 464
 465                 if ($duration > 3600) {
 466                         Logger::info('Longer than 1 hour.', ['priority' => $queue["priority"], 'id' => $queue["id"], 'duration' => round($duration/60, 3)]);
 467                 } elseif ($duration > 600) {
 468                         Logger::info('Longer than 10 minutes.', ['priority' => $queue["priority"], 'id' => $queue["id"], 'duration' => round($duration/60, 3)]);
 469                 } elseif ($duration > 300) {
 470                         Logger::info('Longer than 5 minutes.', ['priority' => $queue["priority"], 'id' => $queue["id"], 'duration' => round($duration/60, 3)]);
 471                 } elseif ($duration > 120) {
 472                         Logger::info('Longer than 2 minutes.', ['priority' => $queue["priority"], 'id' => $queue["id"], 'duration' => round($duration/60, 3)]);
 473                 }
 474
 475                 Logger::info('Process done.', ['priority' => $queue["priority"], 'id' => $queue["id"], 'duration' => round($duration, 3)]);
 476
 477                 DI::profiler()->saveLog(DI::logger(), "ID " . $queue["id"] . ": " . $funcname);
 478
 479                 $cooldown = DI::config()->get("system", "worker_cooldown", 0);
 480
 481                 if ($cooldown > 0) {
 482                         Logger::info('Cooldown.', ['priority' => $queue["priority"], 'id' => $queue["id"], 'cooldown' => $cooldown]);
 483                         sleep($cooldown);
 484                 }
 485         }
 486
 487         /**
 488          * Checks if the number of database connections has reached a critical limit.
 489          *
 490          * @return bool Are more than 3/4 of the maximum connections used?
 491          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 492          */
 493         private static function maxConnectionsReached()
 494         {
 495                 // Fetch the max value from the config. This is needed when the system cannot detect the correct value by itself.
 496                 $max = DI::config()->get("system", "max_connections");
 497
 498                 // Fetch the percentage level where the worker will get active
 499                 $maxlevel = DI::config()->get("system", "max_connections_level", 75);
 500
 501                 if ($max == 0) {
 502                         // the maximum number of possible user connections can be a system variable
 503                         $r = DBA::fetchFirst("SHOW VARIABLES WHERE `variable_name` = 'max_user_connections'");
 504                         if (DBA::isResult($r)) {
 505                                 $max = $r["Value"];
 506                         }
 507                         // Or it can be granted. This overrides the system variable
 508                         $stamp = (float)microtime(true);
 509                         $r = DBA::p('SHOW GRANTS');
 510                         self::$db_duration += (microtime(true) - $stamp);
 511                         while ($grants = DBA::fetch($r)) {
 512                                 $grant = array_pop($grants);
 513                                 if (stristr($grant, "GRANT USAGE ON")) {
 514                                         if (preg_match("/WITH MAX_USER_CONNECTIONS (\d*)/", $grant, $match)) {
 515                                                 $max = $match[1];
 516                                         }
 517                                 }
 518                         }
 519                         DBA::close($r);
 520                 }
 521
 522                 // If $max is set we will use the processlist to determine the current number of connections
 523                 // The processlist only shows entries of the current user
 524                 if ($max != 0) {
 525                         $stamp = (float)microtime(true);
 526                         $r = DBA::p('SHOW PROCESSLIST');
 527                         self::$db_duration += (microtime(true) - $stamp);
 528                         $used = DBA::numRows($r);
 529                         DBA::close($r);
 530
 531                         Logger::info("Connection usage (user values)", ['usage' => $used, 'max' => $max]);
 532
 533                         $level = ($used / $max) * 100;
 534
 535                         if ($level >= $maxlevel) {
 536                                 Logger::notice("Maximum level (".$maxlevel."%) of user connections reached: ".$used."/".$max);
 537                                 return true;
 538                         }
 539                 }
 540
 541                 // We will now check for the system values.
 542                 // This limit could be reached although the user limits are fine.
 543                 $r = DBA::fetchFirst("SHOW VARIABLES WHERE `variable_name` = 'max_connections'");
 544                 if (!DBA::isResult($r)) {
 545                         return false;
 546                 }
 547                 $max = intval($r["Value"]);
 548                 if ($max == 0) {
 549                         return false;
 550                 }
 551                 $r = DBA::fetchFirst("SHOW STATUS WHERE `variable_name` = 'Threads_connected'");
 552                 if (!DBA::isResult($r)) {
 553                         return false;
 554                 }
 555                 $used = intval($r["Value"]);
 556                 if ($used == 0) {
 557                         return false;
 558                 }
 559                 Logger::info("Connection usage (system values)", ['used' => $used, 'max' => $max]);
 560
 561                 $level = $used / $max * 100;
 562
 563                 if ($level < $maxlevel) {
 564                         return false;
 565                 }
 566                 Logger::notice("Maximum level (".$level."%) of system connections reached: ".$used."/".$max);
 567                 return true;
 568         }
 569
 570         /**
 571          * fix the queue entry if the worker process died
 572          *
 573          * @return void
 574          * @throws \Exception
 575          */
 576         private static function killStaleWorkers()
 577         {
 578                 $stamp = (float)microtime(true);
 579                 $entries = DBA::select(
 580                         'workerqueue',
 581                         ['id', 'pid', 'executed', 'priority', 'parameter'],
 582                         ['NOT `done` AND `pid` != 0'],
 583                         ['order' => ['priority', 'created']]
 584                 );
 585                 self::$db_duration += (microtime(true) - $stamp);
 586
 587                 while ($entry = DBA::fetch($entries)) {
 588                         if (!posix_kill($entry["pid"], 0)) {
 589                                 $stamp = (float)microtime(true);
 590                                 DBA::update(
 591                                         'workerqueue',
 592                                         ['executed' => DBA::NULL_DATETIME, 'pid' => 0],
 593                                         ['id' => $entry["id"]]
 594                                 );
 595                                 self::$db_duration += (microtime(true) - $stamp);
 596                                 self::$db_duration_write += (microtime(true) - $stamp);
 597                         } else {
 598                                 // Kill long running processes
 599                                 // Check if the priority is in a valid range
 600                                 if (!in_array($entry["priority"], [PRIORITY_CRITICAL, PRIORITY_HIGH, PRIORITY_MEDIUM, PRIORITY_LOW, PRIORITY_NEGLIGIBLE])) {
 601                                         $entry["priority"] = PRIORITY_MEDIUM;
 602                                 }
 603
 604                                 // Define the maximum durations
 605                                 $max_duration_defaults = [PRIORITY_CRITICAL => 720, PRIORITY_HIGH => 10, PRIORITY_MEDIUM => 60, PRIORITY_LOW => 180, PRIORITY_NEGLIGIBLE => 720];
 606                                 $max_duration = $max_duration_defaults[$entry["priority"]];
 607
 608                                 $argv = json_decode($entry["parameter"], true);
 609                                 if (empty($argv)) {
 610                                         return;
 611                                 }
 612
 613                                 $argv[0] = basename($argv[0]);
 614
 615                                 // How long is the process already running?
 616                                 $duration = (time() - strtotime($entry["executed"])) / 60;
 617                                 if ($duration > $max_duration) {
 618                                         Logger::notice("Worker process ".$entry["pid"]." (".substr(json_encode($argv), 0, 50).") took more than ".$max_duration." minutes. It will be killed now.");
 619                                         posix_kill($entry["pid"], SIGTERM);
 620
 621                                         // We killed the stale process.
 622                                         // To avoid a blocking situation we reschedule the process at the beginning of the queue.
 623                                         // Additionally we are lowering the priority. (But not PRIORITY_CRITICAL)
 624                                         $new_priority = $entry["priority"];
 625                                         if ($entry["priority"] == PRIORITY_HIGH) {
 626                                                 $new_priority = PRIORITY_MEDIUM;
 627                                         } elseif ($entry["priority"] == PRIORITY_MEDIUM) {
 628                                                 $new_priority = PRIORITY_LOW;
 629                                         } elseif ($entry["priority"] != PRIORITY_CRITICAL) {
 630                                                 $new_priority = PRIORITY_NEGLIGIBLE;
 631                                         }
 632                                         $stamp = (float)microtime(true);
 633                                         DBA::update(
 634                                                 'workerqueue',
 635                                                 ['executed' => DBA::NULL_DATETIME, 'created' => DateTimeFormat::utcNow(), 'priority' => $new_priority, 'pid' => 0],
 636                                                 ['id' => $entry["id"]]
 637                                         );
 638                                         self::$db_duration += (microtime(true) - $stamp);
 639                                         self::$db_duration_write += (microtime(true) - $stamp);
 640                                 } else {
 641                                         Logger::info('Process runtime is okay', ['pid' => $entry["pid"], 'duration' => $duration, 'max' => $max_duration, 'command' => substr(json_encode($argv), 0, 50)]);
 642                                 }
 643                         }
 644                 }
 645                 DBA::close($entries);
 646         }
 647
 648         /**
 649          * Checks if the number of active workers exceeds the given limits
 650          *
 651          * @return bool Are there too much workers running?
 652          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 653          */
 654         private static function tooMuchWorkers()
 655         {
 656                 $queues = DI::config()->get("system", "worker_queues", 10);
 657
 658                 $maxqueues = $queues;
 659
 660                 $active = self::activeWorkers();
 661
 662                 // Decrease the number of workers at higher load
 663                 $load = System::currentLoad();
 664                 if ($load) {
 665                         $maxsysload = intval(DI::config()->get("system", "maxloadavg", 20));
 666
 667                         /* Default exponent 3 causes queues to rapidly decrease as load increases.
 668                          * If you have 20 max queues at idle, then you get only 5 queues at 37.1% of $maxsysload.
 669                          * For some environments, this rapid decrease is not needed.
 670                          * With exponent 1, you could have 20 max queues at idle and 13 at 37% of $maxsysload.
 671                          */
 672                         $exponent = intval(DI::config()->get('system', 'worker_load_exponent', 3));
 673                         $slope = pow(max(0, $maxsysload - $load) / $maxsysload, $exponent);
 674                         $queues = intval(ceil($slope * $maxqueues));
 675
 676                         $processlist = '';
 677
 678                         if (DI::config()->get('system', 'worker_jpm')) {
 679                                 $intervals = explode(',', DI::config()->get('system', 'worker_jpm_range'));
 680                                 $jobs_per_minute = [];
 681                                 foreach ($intervals as $interval) {
 682                                         if ($interval == 0) {
 683                                                 continue;
 684                                         } else {
 685                                                 $interval = (int)$interval;
 686                                         }
 687
 688                                         $stamp = (float)microtime(true);
 689                                         $jobs = DBA::p("SELECT COUNT(*) AS `jobs` FROM `workerqueue` WHERE `done` AND `executed` > UTC_TIMESTAMP() - INTERVAL ? MINUTE", $interval);
 690                                         self::$db_duration += (microtime(true) - $stamp);
 691                                         self::$db_duration_stat += (microtime(true) - $stamp);
 692                                         if ($job = DBA::fetch($jobs)) {
 693                                                 $jobs_per_minute[$interval] = number_format($job['jobs'] / $interval, 0);
 694                                         }
 695                                         DBA::close($jobs);
 696                                 }
 697                                 $processlist = ' - jpm: '.implode('/', $jobs_per_minute);
 698                         }
 699
 700                         // Create a list of queue entries grouped by their priority
 701                         $listitem = [0 => ''];
 702
 703                         $idle_workers = $active;
 704
 705                         $deferred = self::deferredEntries();
 706
 707                         if (DI::config()->get('system', 'worker_debug')) {
 708                                 $waiting_processes = 0;
 709                                 // Now adding all processes with workerqueue entries
 710                                 $stamp = (float)microtime(true);
 711                                 $jobs = DBA::p("SELECT COUNT(*) AS `entries`, `priority` FROM `workerqueue` WHERE NOT `done` GROUP BY `priority`");
 712                                 self::$db_duration += (microtime(true) - $stamp);
 713                                 self::$db_duration_stat += (microtime(true) - $stamp);
 714                                 while ($entry = DBA::fetch($jobs)) {
 715                                         $stamp = (float)microtime(true);
 716                                         $processes = DBA::p("SELECT COUNT(*) AS `running` FROM `workerqueue-view` WHERE `priority` = ?", $entry["priority"]);
 717                                         self::$db_duration += (microtime(true) - $stamp);
 718                                         self::$db_duration_stat += (microtime(true) - $stamp);
 719                                         if ($process = DBA::fetch($processes)) {
 720                                                 $idle_workers -= $process["running"];
 721                                                 $waiting_processes += $entry["entries"];
 722                                                 $listitem[$entry["priority"]] = $entry["priority"].":".$process["running"]."/".$entry["entries"];
 723                                         }
 724                                         DBA::close($processes);
 725                                 }
 726                                 DBA::close($jobs);
 727                         } else {
 728                                 $waiting_processes =  self::totalEntries();
 729                                 $stamp = (float)microtime(true);
 730                                 $jobs = DBA::p("SELECT COUNT(*) AS `running`, `priority` FROM `workerqueue-view` GROUP BY `priority` ORDER BY `priority`");
 731                                 self::$db_duration += (microtime(true) - $stamp);
 732                                 self::$db_duration_stat += (microtime(true) - $stamp);
 733
 734                                 while ($entry = DBA::fetch($jobs)) {
 735                                         $idle_workers -= $entry["running"];
 736                                         $listitem[$entry["priority"]] = $entry["priority"].":".$entry["running"];
 737                                 }
 738                                 DBA::close($jobs);
 739                         }
 740
 741                         $waiting_processes -= $deferred;
 742
 743                         $listitem[0] = "0:" . max(0, $idle_workers);
 744
 745                         $processlist .= ' ('.implode(', ', $listitem).')';
 746
 747                         if (DI::config()->get("system", "worker_fastlane", false) && ($queues > 0) && ($active >= $queues) && self::entriesExists()) {
 748                                 $top_priority = self::highestPriority();
 749                                 $high_running = self::processWithPriorityActive($top_priority);
 750
 751                                 if (!$high_running && ($top_priority > PRIORITY_UNDEFINED) && ($top_priority < PRIORITY_NEGLIGIBLE)) {
 752                                         Logger::info("Jobs with a higher priority are waiting but none is executed. Open a fastlane.", ['priority' => $top_priority]);
 753                                         $queues = $active + 1;
 754                                 }
 755                         }
 756
 757                         Logger::notice("Load: " . $load ."/" . $maxsysload . " - processes: " . $deferred . "/" . $active . "/" . $waiting_processes . $processlist . " - maximum: " . $queues . "/" . $maxqueues);
 758
 759                         // Are there fewer workers running as possible? Then fork a new one.
 760                         if (!DI::config()->get("system", "worker_dont_fork", false) && ($queues > ($active + 1)) && self::entriesExists()) {
 761                                 Logger::info("There are fewer workers as possible, fork a new worker.", ['active' => $active, 'queues' => $queues]);
 762                                 if (DI::config()->get('system', 'worker_daemon_mode', false)) {
 763                                         self::IPCSetJobState(true);
 764                                 } else {
 765                                         self::spawnWorker();
 766                                 }
 767                         }
 768                 }
 769
 770                 // if there are too much worker, we don't spawn a new one.
 771                 if (DI::config()->get('system', 'worker_daemon_mode', false) && ($active > $queues)) {
 772                         self::IPCSetJobState(false);
 773                 }
 774
 775                 return $active > $queues;
 776         }
 777
 778         /**
 779          * Returns the number of active worker processes
 780          *
 781          * @return integer Number of active worker processes
 782          * @throws \Exception
 783          */
 784         private static function activeWorkers()
 785         {
 786                 $stamp = (float)microtime(true);
 787                 $count = DBA::count('process', ['command' => 'Worker.php']);
 788                 self::$db_duration += (microtime(true) - $stamp);
 789                 self::$db_duration_count += (microtime(true) - $stamp);
 790                 return $count;
 791         }
 792
 793         /**
 794          * Returns the number of active worker processes
 795          *
 796          * @return array List of worker process ids
 797          * @throws \Exception
 798          */
 799         private static function getWorkerPIDList()
 800         {
 801                 $ids = [];
 802                 $stamp = (float)microtime(true);
 803
 804                 $queues = DBA::p("SELECT `process`.`pid`, COUNT(`workerqueue`.`pid`) AS `entries` FROM `process`
 805                         LEFT JOIN `workerqueue` ON `workerqueue`.`pid` = `process`.`pid` AND NOT `workerqueue`.`done`
 806                         GROUP BY `process`.`pid`");
 807                 while ($queue = DBA::fetch($queues)) {
 808                         $ids[$queue['pid']] = $queue['entries'];
 809                 }
 810                 DBA::close($queues);
 811
 812                 self::$db_duration += (microtime(true) - $stamp);
 813                 self::$db_duration_count += (microtime(true) - $stamp);
 814                 return $ids;
 815         }
 816
 817         /**
 818          * Returns waiting jobs for the current process id
 819          *
 820          * @return array waiting workerqueue jobs
 821          * @throws \Exception
 822          */
 823         private static function getWaitingJobForPID()
 824         {
 825                 $stamp = (float)microtime(true);
 826                 $r = DBA::select('workerqueue', [], ['pid' => getmypid(), 'done' => false]);
 827                 self::$db_duration += (microtime(true) - $stamp);
 828                 if (DBA::isResult($r)) {
 829                         return DBA::toArray($r);
 830                 }
 831                 DBA::close($r);
 832
 833                 return false;
 834         }
 835
 836         /**
 837          * Returns the next jobs that should be executed
 838          * @param int $limit
 839          * @return array array with next jobs
 840          * @throws \Exception
 841          */
 842         private static function nextProcess(int $limit)
 843         {
 844                 $priority = self::nextPriority();
 845                 if (empty($priority)) {
 846                         Logger::info('No tasks found');
 847                         return [];
 848                 }
 849
 850                 $ids = [];
 851                 $stamp = (float)microtime(true);
 852                 $condition = ["`priority` = ? AND `pid` = 0 AND NOT `done` AND `next_try` < ?", $priority, DateTimeFormat::utcNow()];
 853                 $tasks = DBA::select('workerqueue', ['id', 'parameter'], $condition, ['limit' => $limit, 'order' => ['created']]);
 854                 self::$db_duration += (microtime(true) - $stamp);
 855                 while ($task = DBA::fetch($tasks)) {
 856                         $ids[] = $task['id'];
 857                         // Only continue that loop while we are storing commands that can be processed quickly
 858                         $command = json_decode($task['parameter'])[0];
 859                         if (!in_array($command, self::FAST_COMMANDS)) {
 860                                 break;
 861                         }
 862                 }
 863                 DBA::close($tasks);
 864
 865                 Logger::info('Found:', ['priority' => $priority, 'id' => $ids]);
 866                 return $ids;
 867         }
 868
 869         /**
 870          * Returns the priority of the next workerqueue job
 871          *
 872          * @return string priority
 873          * @throws \Exception
 874          */
 875         private static function nextPriority()
 876         {
 877                 $waiting = [];
 878                 $priorities = [PRIORITY_CRITICAL, PRIORITY_HIGH, PRIORITY_MEDIUM, PRIORITY_LOW, PRIORITY_NEGLIGIBLE];
 879                 foreach ($priorities as $priority) {
 880                         $stamp = (float)microtime(true);
 881                         if (DBA::exists('workerqueue', ["`priority` = ? AND `pid` = 0 AND NOT `done` AND `next_try` < ?", $priority, DateTimeFormat::utcNow()])) {
 882                                 $waiting[$priority] = true;
 883                         }
 884                         self::$db_duration += (microtime(true) - $stamp);
 885                 }
 886
 887                 if (!empty($waiting[PRIORITY_CRITICAL])) {
 888                         return PRIORITY_CRITICAL;
 889                 }
 890
 891                 $running = [];
 892                 $running_total = 0;
 893                 $stamp = (float)microtime(true);
 894                 $processes = DBA::p("SELECT COUNT(DISTINCT(`pid`)) AS `running`, `priority` FROM `workerqueue-view` GROUP BY `priority`");
 895                 self::$db_duration += (microtime(true) - $stamp);
 896                 while ($process = DBA::fetch($processes)) {
 897                         $running[$process['priority']] = $process['running'];
 898                         $running_total += $process['running'];
 899                 }
 900                 DBA::close($processes);
 901
 902                 foreach ($priorities as $priority) {
 903                         if (!empty($waiting[$priority]) && empty($running[$priority])) {
 904                                 Logger::info('No running worker found with priority {priority} - assigning it.', ['priority' => $priority]);
 905                                 return $priority;
 906                         }
 907                 }
 908
 909                 $active = max(self::activeWorkers(), $running_total);
 910                 $priorities = max(count($waiting), count($running));
 911                 $exponent = 2;
 912
 913                 $total = 0;
 914                 for ($i = 1; $i <= $priorities; ++$i) {
 915                         $total += pow($i, $exponent);
 916                 }
 917
 918                 $limit = [];
 919                 for ($i = 1; $i <= $priorities; ++$i) {
 920                         $limit[$priorities - $i] = max(1, round($active * (pow($i, $exponent) / $total)));
 921                 }
 922
 923                 $i = 0;
 924                 foreach ($running as $priority => $workers) {
 925                         if ($workers < $limit[$i++]) {
 926                                 Logger::info('Priority {priority} has got {workers} workers out of a limit of {limit}', ['priority' => $priority, 'workers' => $workers, 'limit' => $limit[$i - 1]]);
 927                                 return $priority;
 928                         }
 929                 }
 930
 931                 if (!empty($waiting)) {
 932                         $priority = array_keys($waiting)[0];
 933                         Logger::info('No underassigned priority found, now taking the highest priority.', ['priority' => $priority]);
 934                         return $priority;
 935                 }
 936
 937                 return false;
 938         }
 939
 940         /**
 941          * Find and claim the next worker process for us
 942          *
 943          * @return boolean Have we found something?
 944          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 945          */
 946         private static function findWorkerProcesses()
 947         {
 948                 $fetch_limit = DI::config()->get('system', 'worker_fetch_limit', 1);
 949
 950                 if (DI::config()->get('system', 'worker_multiple_fetch')) {
 951                         $pids = [];
 952                         foreach (self::getWorkerPIDList() as $pid => $count) {
 953                                 if ($count <= $fetch_limit) {
 954                                         $pids[] = $pid;
 955                                 }
 956                         }
 957                         if (empty($pids)) {
 958                                 return;
 959                         }
 960                         $limit = $fetch_limit * count($pids);
 961                 } else {
 962                         $pids = [getmypid()];
 963                         $limit = $fetch_limit;
 964                 }
 965
 966                 $ids = self::nextProcess($limit);
 967                 $limit -= count($ids);
 968
 969                 // If there is not enough results we check without priority limit
 970                 if ($limit > 0) {
 971                         $stamp = (float)microtime(true);
 972                         $condition = ["`pid` = 0 AND NOT `done` AND `next_try` < ?", DateTimeFormat::utcNow()];
 973                         $tasks = DBA::select('workerqueue', ['id', 'parameter'], $condition, ['limit' => $limit, 'order' => ['priority', 'created']]);
 974                         self::$db_duration += (microtime(true) - $stamp);
 975
 976                         while ($task = DBA::fetch($tasks)) {
 977                                 $ids[] = $task['id'];
 978                                 // Only continue that loop while we are storing commands that can be processed quickly
 979                                 $command = json_decode($task['parameter'])[0];
 980                                 if (!in_array($command, self::FAST_COMMANDS)) {
 981                                         break;
 982                                 }
 983                         }
 984                         DBA::close($tasks);
 985                 }
 986
 987                 if (empty($ids)) {
 988                         return;
 989                 }
 990
 991                 // Assign the task ids to the workers
 992                 $worker = [];
 993                 foreach (array_unique($ids) as $id) {
 994                         $pid = next($pids);
 995                         if (!$pid) {
 996                                 $pid = reset($pids);
 997                         }
 998                         $worker[$pid][] = $id;
 999                 }
1000
1001                 $stamp = (float)microtime(true);
1002                 foreach ($worker as $worker_pid => $worker_ids) {
1003                         Logger::info('Set queue entry', ['pid' => $worker_pid, 'ids' => $worker_ids]);
1004                         DBA::update('workerqueue', ['executed' => DateTimeFormat::utcNow(), 'pid' => $worker_pid],
1005                                 ['id' => $worker_ids, 'done' => false, 'pid' => 0]);
1006                 }
1007                 self::$db_duration += (microtime(true) - $stamp);
1008                 self::$db_duration_write += (microtime(true) - $stamp);
1009         }
1010
1011         /**
1012          * Returns the next worker process
1013          *
1014          * @return array worker processes
1015          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1016          */
1017         public static function workerProcess()
1018         {
1019                 // There can already be jobs for us in the queue.
1020                 $waiting = self::getWaitingJobForPID();
1021                 if (!empty($waiting)) {
1022                         return $waiting;
1023                 }
1024
1025                 $stamp = (float)microtime(true);
1026                 if (!DI::lock()->acquire(self::LOCK_PROCESS)) {
1027                         return false;
1028                 }
1029                 self::$lock_duration += (microtime(true) - $stamp);
1030
1031                 self::findWorkerProcesses();
1032
1033                 DI::lock()->release(self::LOCK_PROCESS);
1034
1035                 return self::getWaitingJobForPID();
1036         }
1037
1038         /**
1039          * Removes a workerqueue entry from the current process
1040          *
1041          * @return void
1042          * @throws \Exception
1043          */
1044         public static function unclaimProcess()
1045         {
1046                 $mypid = getmypid();
1047
1048                 $stamp = (float)microtime(true);
1049                 DBA::update('workerqueue', ['executed' => DBA::NULL_DATETIME, 'pid' => 0], ['pid' => $mypid, 'done' => false]);
1050                 self::$db_duration += (microtime(true) - $stamp);
1051                 self::$db_duration_write += (microtime(true) - $stamp);
1052         }
1053
1054         /**
1055          * Call the front end worker
1056          *
1057          * @return void
1058          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1059          */
1060         public static function callWorker()
1061         {
1062                 if (!DI::config()->get("system", "frontend_worker")) {
1063                         return;
1064                 }
1065
1066                 $url = DI::baseUrl() . '/worker';
1067                 DI::httpRequest()->fetch($url, 1);
1068         }
1069
1070         /**
1071          * Call the front end worker if there aren't any active
1072          *
1073          * @return void
1074          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1075          */
1076         public static function executeIfIdle()
1077         {
1078                 if (!DI::config()->get("system", "frontend_worker")) {
1079                         return;
1080                 }
1081
1082                 // Do we have "proc_open"? Then we can fork the worker
1083                 if (function_exists("proc_open")) {
1084                         // When was the last time that we called the worker?
1085                         // Less than one minute? Then we quit
1086                         if ((time() - DI::config()->get("system", "worker_started")) < 60) {
1087                                 return;
1088                         }
1089
1090                         DI::config()->set("system", "worker_started", time());
1091
1092                         // Do we have enough running workers? Then we quit here.
1093                         if (self::tooMuchWorkers()) {
1094                                 // Cleaning dead processes
1095                                 self::killStaleWorkers();
1096                                 DI::modelProcess()->deleteInactive();
1097
1098                                 return;
1099                         }
1100
1101                         self::runCron();
1102
1103                         Logger::info('Call worker');
1104                         self::spawnWorker();
1105                         return;
1106                 }
1107
1108                 // We cannot execute background processes.
1109                 // We now run the processes from the frontend.
1110                 // This won't work with long running processes.
1111                 self::runCron();
1112
1113                 self::clearProcesses();
1114
1115                 $workers = self::activeWorkers();
1116
1117                 if ($workers == 0) {
1118                         self::callWorker();
1119                 }
1120         }
1121
1122         /**
1123          * Removes long running worker processes
1124          *
1125          * @return void
1126          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1127          */
1128         public static function clearProcesses()
1129         {
1130                 $timeout = DI::config()->get("system", "frontend_worker_timeout", 10);
1131
1132                 /// @todo We should clean up the corresponding workerqueue entries as well
1133                 $stamp = (float)microtime(true);
1134                 $condition = ["`created` < ? AND `command` = 'worker.php'",
1135                                 DateTimeFormat::utc("now - ".$timeout." minutes")];
1136                 DBA::delete('process', $condition);
1137                 self::$db_duration = (microtime(true) - $stamp);
1138                 self::$db_duration_write += (microtime(true) - $stamp);
1139         }
1140
1141         /**
1142          * Runs the cron processes
1143          *
1144          * @return void
1145          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1146          */
1147         private static function runCron()
1148         {
1149                 Logger::info('Add cron entries');
1150
1151                 // Check for spooled items
1152                 self::add(['priority' => PRIORITY_HIGH, 'force_priority' => true], 'SpoolPost');
1153
1154                 // Run the cron job that calls all other jobs
1155                 self::add(['priority' => PRIORITY_MEDIUM, 'force_priority' => true], 'Cron');
1156
1157                 // Cleaning dead processes
1158                 self::killStaleWorkers();
1159         }
1160
1161         /**
1162          * Spawns a new worker
1163          *
1164          * @param bool $do_cron
1165          * @return void
1166          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1167          */
1168         public static function spawnWorker($do_cron = false)
1169         {
1170                 $command = 'bin/worker.php';
1171
1172                 $args = ['no_cron' => !$do_cron];
1173
1174                 $a = DI::app();
1175                 $process = new Core\Process(DI::logger(), DI::mode(), DI::config(), DI::modelProcess(), $a->getBasePath(), getmypid());
1176                 $process->run($command, $args);
1177
1178                 // after spawning we have to remove the flag.
1179                 if (DI::config()->get('system', 'worker_daemon_mode', false)) {
1180                         self::IPCSetJobState(false);
1181                 }
1182         }
1183
1184         /**
1185          * Adds tasks to the worker queue
1186          *
1187          * @param (integer|array) priority or parameter array, strings are deprecated and are ignored
1188          *
1189          * next args are passed as $cmd command line
1190          * or: Worker::add(PRIORITY_HIGH, "Notifier", Delivery::DELETION, $drop_id);
1191          * or: Worker::add(array('priority' => PRIORITY_HIGH, 'dont_fork' => true), "CreateShadowEntry", $post_id);
1192          *
1193          * @return boolean "false" if worker queue entry already existed or there had been an error
1194          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
1195          * @note $cmd and string args are surrounded with ""
1196          *
1197          * @hooks 'proc_run'
1198          *    array $arr
1199          *
1200          */
1201         public static function add($cmd)
1202         {
1203                 $args = func_get_args();
1204
1205                 if (!count($args)) {
1206                         return false;
1207                 }
1208
1209                 $arr = ['args' => $args, 'run_cmd' => true];
1210
1211                 Hook::callAll("proc_run", $arr);
1212                 if (!$arr['run_cmd'] || !count($args)) {
1213                         return true;
1214                 }
1215
1216                 $priority = PRIORITY_MEDIUM;
1217                 // Don't fork from frontend tasks by default
1218                 $dont_fork = DI::config()->get("system", "worker_dont_fork", false) || !DI::mode()->isBackend();
1219                 $created = DateTimeFormat::utcNow();
1220                 $force_priority = false;
1221
1222                 $run_parameter = array_shift($args);
1223
1224                 if (is_int($run_parameter)) {
1225                         $priority = $run_parameter;
1226                 } elseif (is_array($run_parameter)) {
1227                         if (isset($run_parameter['priority'])) {
1228                                 $priority = $run_parameter['priority'];
1229                         }
1230                         if (isset($run_parameter['created'])) {
1231                                 $created = $run_parameter['created'];
1232                         }
1233                         if (isset($run_parameter['dont_fork'])) {
1234                                 $dont_fork = $run_parameter['dont_fork'];
1235                         }
1236                         if (isset($run_parameter['force_priority'])) {
1237                                 $force_priority = $run_parameter['force_priority'];
1238                         }
1239                 }
1240
1241                 $parameters = json_encode($args);
1242                 $found = DBA::exists('workerqueue', ['parameter' => $parameters, 'done' => false]);
1243                 $added = false;
1244
1245                 // Quit if there was a database error - a precaution for the update process to 3.5.3
1246                 if (DBA::errorNo() != 0) {
1247                         return false;
1248                 }
1249
1250                 if (!$found) {
1251                         $added = DBA::insert('workerqueue', ['parameter' => $parameters, 'created' => $created, 'priority' => $priority]);
1252                         if (!$added) {
1253                                 return false;
1254                         }
1255                 } elseif ($force_priority) {
1256                         DBA::update('workerqueue', ['priority' => $priority], ['parameter' => $parameters, 'done' => false, 'pid' => 0]);
1257                 }
1258
1259                 // Should we quit and wait for the worker to be called as a cronjob?
1260                 if ($dont_fork) {
1261                         return $added;
1262                 }
1263
1264                 // If there is a lock then we don't have to check for too much worker
1265                 if (!DI::lock()->acquire(self::LOCK_WORKER, 0)) {
1266                         return $added;
1267                 }
1268
1269                 // If there are already enough workers running, don't fork another one
1270                 $quit = self::tooMuchWorkers();
1271                 DI::lock()->release(self::LOCK_WORKER);
1272
1273                 if ($quit) {
1274                         return $added;
1275                 }
1276
1277                 // We tell the daemon that a new job entry exists
1278                 if (DI::config()->get('system', 'worker_daemon_mode', false)) {
1279                         // We don't have to set the IPC flag - this is done in "tooMuchWorkers"
1280                         return $added;
1281                 }
1282
1283                 // Now call the worker to execute the jobs that we just added to the queue
1284                 self::spawnWorker();
1285
1286                 return $added;
1287         }
1288
1289         /**
1290          * Returns the next retrial level for worker jobs.
1291          * This function will skip levels when jobs are older.
1292          *
1293          * @param array $queue Worker queue entry
1294          * @param integer $max_level maximum retrial level
1295          * @return integer the next retrial level value
1296          */
1297         private static function getNextRetrial($queue, $max_level)
1298         {
1299                 $created = strtotime($queue['created']);
1300                 $retrial_time = time() - $created;
1301
1302                 $new_retrial = $queue['retrial'] + 1;
1303                 $total = 0;
1304                 for ($retrial = 0; $retrial <= $max_level + 1; ++$retrial) {
1305                         $delay = (($retrial + 3) ** 4) + (rand(1, 30) * ($retrial + 1));
1306                         $total += $delay;
1307                         if (($total < $retrial_time) && ($retrial > $queue['retrial'])) {
1308                                 $new_retrial = $retrial;
1309                         }
1310                 }
1311                 Logger::info('New retrial for task', ['id' => $queue['id'], 'created' => $queue['created'], 'old' => $queue['retrial'], 'new' => $new_retrial]);
1312                 return $new_retrial;
1313         }
1314
1315         /**
1316          * Defers the current worker entry
1317          *
1318          * @return boolean had the entry been deferred?
1319          */
1320         public static function defer()
1321         {
1322                 if (empty(DI::app()->queue)) {
1323                         return false;
1324                 }
1325
1326                 $queue = DI::app()->queue;
1327
1328                 $retrial = $queue['retrial'];
1329                 $id = $queue['id'];
1330                 $priority = $queue['priority'];
1331
1332                 $max_level = DI::config()->get('system', 'worker_defer_limit');
1333
1334                 $new_retrial = self::getNextRetrial($queue, $max_level);
1335
1336                 if ($new_retrial > $max_level) {
1337                         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]);
1338                         return false;
1339                 }
1340
1341                 // Calculate the delay until the next trial
1342                 $delay = (($new_retrial + 2) ** 4) + (rand(1, 30) * ($new_retrial));
1343                 $next = DateTimeFormat::utc('now + ' . $delay . ' seconds');
1344
1345                 if (($priority < PRIORITY_MEDIUM) && ($new_retrial > 3)) {
1346                         $priority = PRIORITY_MEDIUM;
1347                 } elseif (($priority < PRIORITY_LOW) && ($new_retrial > 6)) {
1348                         $priority = PRIORITY_LOW;
1349                 } elseif (($priority < PRIORITY_NEGLIGIBLE) && ($new_retrial > 8)) {
1350                         $priority = PRIORITY_NEGLIGIBLE;
1351                 }
1352
1353                 Logger::info('Deferred task', ['id' => $id, 'retrial' => $new_retrial, 'created' => $queue['created'], 'next_execution' => $next, 'old_prio' => $queue['priority'], 'new_prio' => $priority]);
1354
1355                 $stamp = (float)microtime(true);
1356                 $fields = ['retrial' => $new_retrial, 'next_try' => $next, 'executed' => DBA::NULL_DATETIME, 'pid' => 0, 'priority' => $priority];
1357                 DBA::update('workerqueue', $fields, ['id' => $id]);
1358                 self::$db_duration += (microtime(true) - $stamp);
1359                 self::$db_duration_write += (microtime(true) - $stamp);
1360
1361                 return true;
1362         }
1363
1364         /**
1365          * Set the flag if some job is waiting
1366          *
1367          * @param boolean $jobs Is there a waiting job?
1368          * @throws \Exception
1369          */
1370         public static function IPCSetJobState($jobs)
1371         {
1372                 $stamp = (float)microtime(true);
1373                 DBA::update('worker-ipc', ['jobs' => $jobs], ['key' => 1], true);
1374                 self::$db_duration += (microtime(true) - $stamp);
1375                 self::$db_duration_write += (microtime(true) - $stamp);
1376         }
1377
1378         /**
1379          * Checks if some worker job waits to be executed
1380          *
1381          * @return bool
1382          * @throws \Exception
1383          */
1384         public static function IPCJobsExists()
1385         {
1386                 $stamp = (float)microtime(true);
1387                 $row = DBA::selectFirst('worker-ipc', ['jobs'], ['key' => 1]);
1388                 self::$db_duration += (microtime(true) - $stamp);
1389
1390                 // When we don't have a row, no job is running
1391                 if (!DBA::isResult($row)) {
1392                         return false;
1393                 }
1394
1395                 return (bool)$row['jobs'];
1396         }
1397
1398         /**
1399          * Check if the system is inside the defined maintenance window
1400          *
1401          * @return boolean
1402          */
1403         public static function isInMaintenanceWindow(bool $check_last_execution = false)
1404         {
1405                 // Calculate the seconds of the start end end of the maintenance window
1406                 $start = strtotime(DI::config()->get('system', 'maintenance_start')) % 86400;
1407                 $end = strtotime(DI::config()->get('system', 'maintenance_end')) % 86400;
1408
1409                 Logger::info('Maintenance window', ['start' => date('H:i:s', $start), 'end' => date('H:i:s', $end)]);
1410
1411                 if ($check_last_execution) {
1412                         // Calculate the window duration
1413                         $duration = max($start, $end) - min($start, $end);
1414
1415                         // Quit when the last cron execution had been after the previous window
1416                         $last_cron = DI::config()->get('system', 'last_cron_daily');
1417                         if ($last_cron + $duration > time()) {
1418                                 Logger::info('The Daily cron had been executed recently', ['last' => date(DateTimeFormat::MYSQL, $last_cron), 'start' => date('H:i:s', $start), 'end' => date('H:i:s', $end)]);
1419                                 return false;
1420                         }
1421                 }
1422
1423                 $current = time() % 86400;
1424
1425                 if ($start < $end) {
1426                         // Execute if we are inside the window
1427                         $execute = ($current >= $start) && ($current <= $end);
1428                 } else {
1429                         // Don't execute if we are outside the window
1430                         $execute = !(($current > $end) && ($current < $start));
1431                 }
1432
1433                 if ($execute) {
1434                         Logger::info('We are inside the maintenance window', ['current' => date('H:i:s', $current), 'start' => date('H:i:s', $start), 'end' => date('H:i:s', $end)]);
1435                 } else {
1436                         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)]);
1437                 }
1438
1439                 return $execute;
1440         }
1441 }