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