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