src/Core/Worker.php

   1 <?php
   2 /**
   3  * @file src/Core/Worker.php
   4  */
   5 namespace Friendica\Core;
   6
   7 use Friendica\BaseObject;
   8 use Friendica\Database\DBA;
   9 use Friendica\Model\Process;
  10 use Friendica\Util\DateTimeFormat;
  11 use Friendica\Util\Network;
  12
  13 require_once 'include/dba.php';
  14
  15 /**
  16  * @file src/Core/Worker.php
  17  *
  18  * @brief Contains the class for the worker background job processing
  19  */
  20
  21 /**
  22  * @brief Worker methods
  23  */
  24 class Worker
  25 {
  26         private static $up_start;
  27         private static $db_duration;
  28         private static $last_update;
  29         private static $lock_duration;
  30
  31         /**
  32          * @brief Processes the tasks that are in the workerqueue table
  33          *
  34          * @param boolean $run_cron Should the cron processes be executed?
  35          * @return void
  36          */
  37         public static function processQueue($run_cron = true)
  38         {
  39                 $a = get_app();
  40
  41                 self::$up_start = microtime(true);
  42
  43                 // At first check the maximum load. We shouldn't continue with a high load
  44                 if ($a->isMaxLoadReached()) {
  45                         logger('Pre check: maximum load reached, quitting.', LOGGER_DEBUG);
  46                         return;
  47                 }
  48
  49                 // We now start the process. This is done after the load check since this could increase the load.
  50                 self::startProcess();
  51
  52                 // Kill stale processes every 5 minutes
  53                 $last_cleanup = Config::get('system', 'worker_last_cleaned', 0);
  54                 if (time() > ($last_cleanup + 300)) {
  55                         Config::set('system', 'worker_last_cleaned', time());
  56                         self::killStaleWorkers();
  57                 }
  58
  59                 // Count active workers and compare them with a maximum value that depends on the load
  60                 if (self::tooMuchWorkers()) {
  61                         logger('Pre check: Active worker limit reached, quitting.', LOGGER_DEBUG);
  62                         return;
  63                 }
  64
  65                 // Do we have too few memory?
  66                 if ($a->isMinMemoryReached()) {
  67                         logger('Pre check: Memory limit reached, quitting.', LOGGER_DEBUG);
  68                         return;
  69                 }
  70
  71                 // Possibly there are too much database connections
  72                 if (self::maxConnectionsReached()) {
  73                         logger('Pre check: maximum connections reached, quitting.', LOGGER_DEBUG);
  74                         return;
  75                 }
  76
  77                 // Possibly there are too much database processes that block the system
  78                 if ($a->isMaxProcessesReached()) {
  79                         logger('Pre check: maximum processes reached, quitting.', LOGGER_DEBUG);
  80                         return;
  81                 }
  82
  83                 // Now we start additional cron processes if we should do so
  84                 if ($run_cron) {
  85                         self::runCron();
  86                 }
  87
  88                 $starttime = time();
  89
  90                 // We fetch the next queue entry that is about to be executed
  91                 while ($r = self::workerProcess($passing_slow)) {
  92                         // When we are processing jobs with a lower priority, we don't refetch new jobs
  93                         // Otherwise fast jobs could wait behind slow ones and could be blocked.
  94                         $refetched = $passing_slow;
  95
  96                         foreach ($r as $entry) {
  97                                 // Assure that the priority is an integer value
  98                                 $entry['priority'] = (int)$entry['priority'];
  99
 100                                 // The work will be done
 101                                 if (!self::execute($entry)) {
 102                                         logger('Process execution failed, quitting.', LOGGER_DEBUG);
 103                                         return;
 104                                 }
 105
 106                                 // If possible we will fetch new jobs for this worker
 107                                 if (!$refetched && Lock::acquire('worker_process', 0)) {
 108                                         $stamp = (float)microtime(true);
 109                                         $refetched = self::findWorkerProcesses($passing_slow);
 110                                         self::$db_duration += (microtime(true) - $stamp);
 111                                         Lock::release('worker_process');
 112                                 }
 113                         }
 114
 115                         // To avoid the quitting of multiple workers only one worker at a time will execute the check
 116                         if (Lock::acquire('worker', 0)) {
 117                                 $stamp = (float)microtime(true);
 118                                 // Count active workers and compare them with a maximum value that depends on the load
 119                                 if (self::tooMuchWorkers()) {
 120                                         logger('Active worker limit reached, quitting.', LOGGER_DEBUG);
 121                                         Lock::release('worker');
 122                                         return;
 123                                 }
 124
 125                                 // Check free memory
 126                                 if ($a->isMinMemoryReached()) {
 127                                         logger('Memory limit reached, quitting.', LOGGER_DEBUG);
 128                                         Lock::release('worker');
 129                                         return;
 130                                 }
 131                                 Lock::release('worker');
 132                                 self::$db_duration += (microtime(true) - $stamp);
 133                         }
 134
 135                         // Quit the worker once every 5 minutes
 136                         if (time() > ($starttime + 300)) {
 137                                 logger('Process lifetime reached, quitting.', LOGGER_DEBUG);
 138                                 return;
 139                         }
 140                 }
 141
 142                 // Cleaning up. Possibly not needed, but it doesn't harm anything.
 143                 if (Config::get('system', 'worker_daemon_mode', false)) {
 144                         self::IPCSetJobState(false);
 145                 }
 146                 logger("Couldn't select a workerqueue entry, quitting process " . getmypid() . ".", LOGGER_DEBUG);
 147         }
 148
 149         /**
 150          * @brief Returns the number of non executed entries in the worker queue
 151          *
 152          * @return integer Number of non executed entries in the worker queue
 153          */
 154         private static function totalEntries()
 155         {
 156                 return DBA::count('workerqueue', ["`executed` <= ? AND NOT `done` AND `next_try` < ?",
 157                         DBA::NULL_DATETIME, DateTimeFormat::utcNow()]);
 158         }
 159
 160         /**
 161          * @brief Returns the highest priority in the worker queue that isn't executed
 162          *
 163          * @return integer Number of active worker processes
 164          */
 165         private static function highestPriority()
 166         {
 167                 $condition = ["`executed` <= ? AND NOT `done` AND `next_try` < ?", DBA::NULL_DATETIME, DateTimeFormat::utcNow()];
 168                 $workerqueue = DBA::selectFirst('workerqueue', ['priority'], $condition, ['order' => ['priority']]);
 169                 if (DBA::isResult($workerqueue)) {
 170                         return $workerqueue["priority"];
 171                 } else {
 172                         return 0;
 173                 }
 174         }
 175
 176         /**
 177          * @brief Returns if a process with the given priority is running
 178          *
 179          * @param integer $priority The priority that should be checked
 180          *
 181          * @return integer Is there a process running with that priority?
 182          */
 183         private static function processWithPriorityActive($priority)
 184         {
 185                 $condition = ["`priority` <= ? AND `executed` > ? AND NOT `done` AND `next_try` < ?",
 186                         $priority, DBA::NULL_DATETIME, DateTimeFormat::utcNow()];
 187                 return DBA::exists('workerqueue', $condition);
 188         }
 189
 190         /**
 191          * @brief Execute a worker entry
 192          *
 193          * @param array $queue Workerqueue entry
 194          *
 195          * @return boolean "true" if further processing should be stopped
 196          */
 197         public static function execute($queue)
 198         {
 199                 $a = get_app();
 200
 201                 $mypid = getmypid();
 202
 203                 // Quit when in maintenance
 204                 if (Config::get('system', 'maintenance', false, true)) {
 205                         logger("Maintenance mode - quit process ".$mypid, LOGGER_DEBUG);
 206                         return false;
 207                 }
 208
 209                 // Constantly check the number of parallel database processes
 210                 if ($a->isMaxProcessesReached()) {
 211                         logger("Max processes reached for process ".$mypid, LOGGER_DEBUG);
 212                         return false;
 213                 }
 214
 215                 // Constantly check the number of available database connections to let the frontend be accessible at any time
 216                 if (self::maxConnectionsReached()) {
 217                         logger("Max connection reached for process ".$mypid, LOGGER_DEBUG);
 218                         return false;
 219                 }
 220
 221                 $argv = json_decode($queue["parameter"], true);
 222
 223                 // Check for existance and validity of the include file
 224                 $include = $argv[0];
 225
 226                 if (method_exists(sprintf('Friendica\Worker\%s', $include), 'execute')) {
 227                         // We constantly update the "executed" date every minute to avoid being killed too soon
 228                         if (!isset(self::$last_update)) {
 229                                 self::$last_update = strtotime($queue["executed"]);
 230                         }
 231
 232                         $age = (time() - self::$last_update) / 60;
 233                         self::$last_update = time();
 234
 235                         if ($age > 1) {
 236                                 $stamp = (float)microtime(true);
 237                                 DBA::update('workerqueue', ['executed' => DateTimeFormat::utcNow()], ['pid' => $mypid, 'done' => false]);
 238                                 self::$db_duration += (microtime(true) - $stamp);
 239                         }
 240
 241                         array_shift($argv);
 242
 243                         self::execFunction($queue, $include, $argv, true);
 244
 245                         $stamp = (float)microtime(true);
 246
 247                         $condition = ["`id` = ? AND `next_try` < ?", $queue['id'], DateTimeFormat::utcNow()];
 248                         if (DBA::update('workerqueue', ['done' => true], $condition)) {
 249                                 Config::set('system', 'last_worker_execution', DateTimeFormat::utcNow());
 250                         }
 251                         self::$db_duration = (microtime(true) - $stamp);
 252
 253                         return true;
 254                 }
 255
 256                 // The script could be provided as full path or only with the function name
 257                 if ($include == basename($include)) {
 258                         $include = "include/".$include.".php";
 259                 }
 260
 261                 if (!validate_include($include)) {
 262                         logger("Include file ".$argv[0]." is not valid!");
 263                         DBA::delete('workerqueue', ['id' => $queue["id"]]);
 264                         return true;
 265                 }
 266
 267                 require_once $include;
 268
 269                 $funcname = str_replace(".php", "", basename($argv[0]))."_run";
 270
 271                 if (function_exists($funcname)) {
 272                         // We constantly update the "executed" date every minute to avoid being killed too soon
 273                         if (!isset(self::$last_update)) {
 274                                 self::$last_update = strtotime($queue["executed"]);
 275                         }
 276
 277                         $age = (time() - self::$last_update) / 60;
 278                         self::$last_update = time();
 279
 280                         if ($age > 1) {
 281                                 $stamp = (float)microtime(true);
 282                                 DBA::update('workerqueue', ['executed' => DateTimeFormat::utcNow()], ['pid' => $mypid, 'done' => false]);
 283                                 self::$db_duration += (microtime(true) - $stamp);
 284                         }
 285
 286                         self::execFunction($queue, $funcname, $argv, false);
 287
 288                         $stamp = (float)microtime(true);
 289                         if (DBA::update('workerqueue', ['done' => true], ['id' => $queue["id"]])) {
 290                                 Config::set('system', 'last_worker_execution', DateTimeFormat::utcNow());
 291                         }
 292                         self::$db_duration = (microtime(true) - $stamp);
 293                 } else {
 294                         logger("Function ".$funcname." does not exist");
 295                         DBA::delete('workerqueue', ['id' => $queue["id"]]);
 296                 }
 297
 298                 return true;
 299         }
 300
 301         /**
 302          * @brief Execute a function from the queue
 303          *
 304          * @param array   $queue       Workerqueue entry
 305          * @param string  $funcname    name of the function
 306          * @param array   $argv        Array of values to be passed to the function
 307          * @param boolean $method_call boolean
 308          * @return void
 309          */
 310         private static function execFunction($queue, $funcname, $argv, $method_call)
 311         {
 312                 $a = get_app();
 313
 314                 $mypid = getmypid();
 315
 316                 $argc = count($argv);
 317
 318                 $new_process_id = System::processID("wrk");
 319
 320                 logger("Process ".$mypid." - Prio ".$queue["priority"]." - ID ".$queue["id"].": ".$funcname." ".$queue["parameter"]." - Process PID: ".$new_process_id);
 321
 322                 $stamp = (float)microtime(true);
 323
 324                 // We use the callstack here to analyze the performance of executed worker entries.
 325                 // For this reason the variables have to be initialized.
 326                 if (Config::get("system", "profiler")) {
 327                         $a->performance["start"] = microtime(true);
 328                         $a->performance["database"] = 0;
 329                         $a->performance["database_write"] = 0;
 330                         $a->performance["cache"] = 0;
 331                         $a->performance["cache_write"] = 0;
 332                         $a->performance["network"] = 0;
 333                         $a->performance["file"] = 0;
 334                         $a->performance["rendering"] = 0;
 335                         $a->performance["parser"] = 0;
 336                         $a->performance["marktime"] = 0;
 337                         $a->performance["markstart"] = microtime(true);
 338                         $a->callstack = [];
 339                 }
 340
 341                 // For better logging create a new process id for every worker call
 342                 // But preserve the old one for the worker
 343                 $old_process_id = $a->process_id;
 344                 $a->process_id = $new_process_id;
 345                 $a->queue = $queue;
 346
 347                 $up_duration = number_format(microtime(true) - self::$up_start, 3);
 348
 349                 // Reset global data to avoid interferences
 350                 unset($_SESSION);
 351
 352                 if ($method_call) {
 353                         call_user_func_array(sprintf('Friendica\Worker\%s::execute', $funcname), $argv);
 354                 } else {
 355                         $funcname($argv, $argc);
 356                 }
 357
 358                 $a->process_id = $old_process_id;
 359                 unset($a->queue);
 360
 361                 $duration = (microtime(true) - $stamp);
 362
 363                 self::$up_start = microtime(true);
 364
 365                 /* With these values we can analyze how effective the worker is.
 366                  * The database and rest time should be low since this is the unproductive time.
 367                  * The execution time is the productive time.
 368                  * By changing parameters like the maximum number of workers we can check the effectivness.
 369                 */
 370                 logger(
 371                         'DB: '.number_format(self::$db_duration, 2).
 372                         ' - Lock: '.number_format(self::$lock_duration, 2).
 373                         ' - Rest: '.number_format($up_duration - self::$db_duration - self::$lock_duration, 2).
 374                         ' - Execution: '.number_format($duration, 2),
 375                         LOGGER_DEBUG
 376                 );
 377
 378                 self::$lock_duration = 0;
 379
 380                 if ($duration > 3600) {
 381                         logger("Prio ".$queue["priority"].": ".$queue["parameter"]." - longer than 1 hour (".round($duration/60, 3).")", LOGGER_DEBUG);
 382                 } elseif ($duration > 600) {
 383                         logger("Prio ".$queue["priority"].": ".$queue["parameter"]." - longer than 10 minutes (".round($duration/60, 3).")", LOGGER_DEBUG);
 384                 } elseif ($duration > 300) {
 385                         logger("Prio ".$queue["priority"].": ".$queue["parameter"]." - longer than 5 minutes (".round($duration/60, 3).")", LOGGER_DEBUG);
 386                 } elseif ($duration > 120) {
 387                         logger("Prio ".$queue["priority"].": ".$queue["parameter"]." - longer than 2 minutes (".round($duration/60, 3).")", LOGGER_DEBUG);
 388                 }
 389
 390                 logger("Process ".$mypid." - Prio ".$queue["priority"]." - ID ".$queue["id"].": ".$funcname." - done in ".$duration." seconds. Process PID: ".$new_process_id);
 391
 392                 // Write down the performance values into the log
 393                 if (Config::get("system", "profiler")) {
 394                         $duration = microtime(true)-$a->performance["start"];
 395
 396                         $o = '';
 397                         if (Config::get("rendertime", "callstack")) {
 398                                 if (isset($a->callstack["database"])) {
 399                                         $o .= "\nDatabase Read:\n";
 400                                         foreach ($a->callstack["database"] as $func => $time) {
 401                                                 $time = round($time, 3);
 402                                                 if ($time > 0) {
 403                                                         $o .= $func.": ".$time."\n";
 404                                                 }
 405                                         }
 406                                 }
 407                                 if (isset($a->callstack["database_write"])) {
 408                                         $o .= "\nDatabase Write:\n";
 409                                         foreach ($a->callstack["database_write"] as $func => $time) {
 410                                                 $time = round($time, 3);
 411                                                 if ($time > 0) {
 412                                                         $o .= $func.": ".$time."\n";
 413                                                 }
 414                                         }
 415                                 }
 416                                 if (isset($a->callstack["dache"])) {
 417                                         $o .= "\nCache Read:\n";
 418                                         foreach ($a->callstack["dache"] as $func => $time) {
 419                                                 $time = round($time, 3);
 420                                                 if ($time > 0) {
 421                                                         $o .= $func.": ".$time."\n";
 422                                                 }
 423                                         }
 424                                 }
 425                                 if (isset($a->callstack["dache_write"])) {
 426                                         $o .= "\nCache Write:\n";
 427                                         foreach ($a->callstack["dache_write"] as $func => $time) {
 428                                                 $time = round($time, 3);
 429                                                 if ($time > 0) {
 430                                                         $o .= $func.": ".$time."\n";
 431                                                 }
 432                                         }
 433                                 }
 434                                 if (isset($a->callstack["network"])) {
 435                                         $o .= "\nNetwork:\n";
 436                                         foreach ($a->callstack["network"] as $func => $time) {
 437                                                 $time = round($time, 3);
 438                                                 if ($time > 0) {
 439                                                         $o .= $func.": ".$time."\n";
 440                                                 }
 441                                         }
 442                                 }
 443                         }
 444
 445                         logger(
 446                                 "ID ".$queue["id"].": ".$funcname.": ".sprintf(
 447                                         "DB: %s/%s, Cache: %s/%s, Net: %s, I/O: %s, Other: %s, Total: %s".$o,
 448                                         number_format($a->performance["database"] - $a->performance["database_write"], 2),
 449                                         number_format($a->performance["database_write"], 2),
 450                                         number_format($a->performance["cache"], 2),
 451                                         number_format($a->performance["cache_write"], 2),
 452                                         number_format($a->performance["network"], 2),
 453                                         number_format($a->performance["file"], 2),
 454                                         number_format($duration - ($a->performance["database"]
 455                                                 + $a->performance["cache"] + $a->performance["cache_write"]
 456                                                 + $a->performance["network"] + $a->performance["file"]), 2),
 457                                         number_format($duration, 2)
 458                                 ),
 459                                 LOGGER_DEBUG
 460                         );
 461                 }
 462
 463                 $cooldown = Config::get("system", "worker_cooldown", 0);
 464
 465                 if ($cooldown > 0) {
 466                         logger("Process ".$mypid." - Prio ".$queue["priority"]." - ID ".$queue["id"].": ".$funcname." - in cooldown for ".$cooldown." seconds");
 467                         sleep($cooldown);
 468                 }
 469         }
 470
 471         /**
 472          * @brief Checks if the number of database connections has reached a critical limit.
 473          *
 474          * @return bool Are more than 3/4 of the maximum connections used?
 475          */
 476         private static function maxConnectionsReached()
 477         {
 478                 // Fetch the max value from the config. This is needed when the system cannot detect the correct value by itself.
 479                 $max = Config::get("system", "max_connections");
 480
 481                 // Fetch the percentage level where the worker will get active
 482                 $maxlevel = Config::get("system", "max_connections_level", 75);
 483
 484                 if ($max == 0) {
 485                         // the maximum number of possible user connections can be a system variable
 486                         $r = DBA::fetchFirst("SHOW VARIABLES WHERE `variable_name` = 'max_user_connections'");
 487                         if (DBA::isResult($r)) {
 488                                 $max = $r["Value"];
 489                         }
 490                         // Or it can be granted. This overrides the system variable
 491                         $r = DBA::p('SHOW GRANTS');
 492                         while ($grants = DBA::fetch($r)) {
 493                                 $grant = array_pop($grants);
 494                                 if (stristr($grant, "GRANT USAGE ON")) {
 495                                         if (preg_match("/WITH MAX_USER_CONNECTIONS (\d*)/", $grant, $match)) {
 496                                                 $max = $match[1];
 497                                         }
 498                                 }
 499                         }
 500                         DBA::close($r);
 501                 }
 502
 503                 // If $max is set we will use the processlist to determine the current number of connections
 504                 // The processlist only shows entries of the current user
 505                 if ($max != 0) {
 506                         $r = DBA::p('SHOW PROCESSLIST');
 507                         $used = DBA::numRows($r);
 508                         DBA::close($r);
 509
 510                         logger("Connection usage (user values): ".$used."/".$max, LOGGER_DEBUG);
 511
 512                         $level = ($used / $max) * 100;
 513
 514                         if ($level >= $maxlevel) {
 515                                 logger("Maximum level (".$maxlevel."%) of user connections reached: ".$used."/".$max);
 516                                 return true;
 517                         }
 518                 }
 519
 520                 // We will now check for the system values.
 521                 // This limit could be reached although the user limits are fine.
 522                 $r = DBA::fetchFirst("SHOW VARIABLES WHERE `variable_name` = 'max_connections'");
 523                 if (!DBA::isResult($r)) {
 524                         return false;
 525                 }
 526                 $max = intval($r["Value"]);
 527                 if ($max == 0) {
 528                         return false;
 529                 }
 530                 $r = DBA::fetchFirst("SHOW STATUS WHERE `variable_name` = 'Threads_connected'");
 531                 if (!DBA::isResult($r)) {
 532                         return false;
 533                 }
 534                 $used = intval($r["Value"]);
 535                 if ($used == 0) {
 536                         return false;
 537                 }
 538                 logger("Connection usage (system values): ".$used."/".$max, LOGGER_DEBUG);
 539
 540                 $level = $used / $max * 100;
 541
 542                 if ($level < $maxlevel) {
 543                         return false;
 544                 }
 545                 logger("Maximum level (".$level."%) of system connections reached: ".$used."/".$max);
 546                 return true;
 547         }
 548
 549         /**
 550          * @brief fix the queue entry if the worker process died
 551          * @return void
 552          */
 553         private static function killStaleWorkers()
 554         {
 555                 $entries = DBA::select(
 556                         'workerqueue',
 557                         ['id', 'pid', 'executed', 'priority', 'parameter'],
 558                         ['`executed` > ? AND NOT `done` AND `pid` != 0', DBA::NULL_DATETIME],
 559                         ['order' => ['priority', 'created']]
 560                 );
 561
 562                 while ($entry = DBA::fetch($entries)) {
 563                         if (!posix_kill($entry["pid"], 0)) {
 564                                 DBA::update(
 565                                         'workerqueue',
 566                                         ['executed' => DBA::NULL_DATETIME, 'pid' => 0],
 567                                         ['id' => $entry["id"]]
 568                                 );
 569                         } else {
 570                                 // Kill long running processes
 571                                 // Check if the priority is in a valid range
 572                                 if (!in_array($entry["priority"], [PRIORITY_CRITICAL, PRIORITY_HIGH, PRIORITY_MEDIUM, PRIORITY_LOW, PRIORITY_NEGLIGIBLE])) {
 573                                         $entry["priority"] = PRIORITY_MEDIUM;
 574                                 }
 575
 576                                 // Define the maximum durations
 577                                 $max_duration_defaults = [PRIORITY_CRITICAL => 720, PRIORITY_HIGH => 10, PRIORITY_MEDIUM => 60, PRIORITY_LOW => 180, PRIORITY_NEGLIGIBLE => 720];
 578                                 $max_duration = $max_duration_defaults[$entry["priority"]];
 579
 580                                 $argv = json_decode($entry["parameter"], true);
 581                                 $argv[0] = basename($argv[0]);
 582
 583                                 // How long is the process already running?
 584                                 $duration = (time() - strtotime($entry["executed"])) / 60;
 585                                 if ($duration > $max_duration) {
 586                                         logger("Worker process ".$entry["pid"]." (".substr(json_encode($argv), 0, 50).") took more than ".$max_duration." minutes. It will be killed now.");
 587                                         posix_kill($entry["pid"], SIGTERM);
 588
 589                                         // We killed the stale process.
 590                                         // To avoid a blocking situation we reschedule the process at the beginning of the queue.
 591                                         // Additionally we are lowering the priority. (But not PRIORITY_CRITICAL)
 592                                         $new_priority = $entry["priority"];
 593                                         if ($entry["priority"] == PRIORITY_HIGH) {
 594                                                 $new_priority = PRIORITY_MEDIUM;
 595                                         } elseif ($entry["priority"] == PRIORITY_MEDIUM) {
 596                                                 $new_priority = PRIORITY_LOW;
 597                                         } elseif ($entry["priority"] != PRIORITY_CRITICAL) {
 598                                                 $new_priority = PRIORITY_NEGLIGIBLE;
 599                                         }
 600                                         DBA::update(
 601                                                 'workerqueue',
 602                                                 ['executed' => DBA::NULL_DATETIME, 'created' => DateTimeFormat::utcNow(), 'priority' => $new_priority, 'pid' => 0],
 603                                                 ['id' => $entry["id"]]
 604                                         );
 605                                 } else {
 606                                         logger("Worker process ".$entry["pid"]." (".substr(json_encode($argv), 0, 50).") now runs for ".round($duration)." of ".$max_duration." allowed minutes. That's okay.", LOGGER_DEBUG);
 607                                 }
 608                         }
 609                 }
 610         }
 611
 612         /**
 613          * @brief Checks if the number of active workers exceeds the given limits
 614          *
 615          * @return bool Are there too much workers running?
 616          */
 617         public static function tooMuchWorkers()
 618         {
 619                 $queues = Config::get("system", "worker_queues", 4);
 620
 621                 $maxqueues = $queues;
 622
 623                 $active = self::activeWorkers();
 624
 625                 // Decrease the number of workers at higher load
 626                 $load = System::currentLoad();
 627                 if ($load) {
 628                         $maxsysload = intval(Config::get("system", "maxloadavg", 50));
 629
 630                         /* Default exponent 3 causes queues to rapidly decrease as load increases.
 631                          * If you have 20 max queues at idle, then you get only 5 queues at 37.1% of $maxsysload.
 632                          * For some environments, this rapid decrease is not needed.
 633                          * With exponent 1, you could have 20 max queues at idle and 13 at 37% of $maxsysload.
 634                          */
 635                         $exponent = intval(Config::get('system', 'worker_load_exponent', 3));
 636                         $slope = pow(max(0, $maxsysload - $load) / $maxsysload, $exponent);
 637                         $queues = intval(ceil($slope * $maxqueues));
 638
 639                         $processlist = '';
 640
 641                         if (Config::get('system', 'worker_debug')) {
 642                                 // Create a list of queue entries grouped by their priority
 643                                 $listitem = [];
 644
 645                                 // Adding all processes with no workerqueue entry
 646                                 $processes = DBA::p(
 647                                         "SELECT COUNT(*) AS `running` FROM `process` WHERE NOT EXISTS
 648                                                         (SELECT id FROM `workerqueue`
 649                                                         WHERE `workerqueue`.`pid` = `process`.`pid` AND NOT `done` AND `pid` != ?)",
 650                                         getmypid()
 651                                 );
 652
 653                                 if ($process = DBA::fetch($processes)) {
 654                                         $listitem[0] = "0:".$process["running"];
 655                                 }
 656                                 DBA::close($processes);
 657
 658                                 // Now adding all processes with workerqueue entries
 659                                 $entries = DBA::p("SELECT COUNT(*) AS `entries`, `priority` FROM `workerqueue` WHERE NOT `done` GROUP BY `priority`");
 660                                 while ($entry = DBA::fetch($entries)) {
 661                                         $processes = DBA::p("SELECT COUNT(*) AS `running` FROM `process` INNER JOIN `workerqueue` ON `workerqueue`.`pid` = `process`.`pid` AND NOT `done` WHERE `priority` = ?", $entry["priority"]);
 662                                         if ($process = DBA::fetch($processes)) {
 663                                                 $listitem[$entry["priority"]] = $entry["priority"].":".$process["running"]."/".$entry["entries"];
 664                                         }
 665                                         DBA::close($processes);
 666                                 }
 667                                 DBA::close($entries);
 668
 669                                 $intervals = [1, 10, 60];
 670                                 $jobs_per_minute = [];
 671                                 foreach ($intervals as $interval) {
 672                                         $jobs = DBA::p("SELECT COUNT(*) AS `jobs` FROM `workerqueue` WHERE `done` AND `executed` > UTC_TIMESTAMP() - INTERVAL ".intval($interval)." MINUTE");
 673                                         if ($job = DBA::fetch($jobs)) {
 674                                                 $jobs_per_minute[$interval] = number_format($job['jobs'] / $interval, 0);
 675                                         }
 676                                         DBA::close($jobs);
 677                                 }
 678                                 $processlist = ' - jpm: '.implode('/', $jobs_per_minute).' ('.implode(', ', $listitem).')';
 679                         }
 680
 681                         $entries = self::totalEntries();
 682
 683                         if (Config::get("system", "worker_fastlane", false) && ($queues > 0) && ($entries > 0) && ($active >= $queues)) {
 684                                 $top_priority = self::highestPriority();
 685                                 $high_running = self::processWithPriorityActive($top_priority);
 686
 687                                 if (!$high_running && ($top_priority > PRIORITY_UNDEFINED) && ($top_priority < PRIORITY_NEGLIGIBLE)) {
 688                                         logger("There are jobs with priority ".$top_priority." waiting but none is executed. Open a fastlane.", LOGGER_DEBUG);
 689                                         $queues = $active + 1;
 690                                 }
 691                         }
 692
 693                         logger("Load: ".$load."/".$maxsysload." - processes: ".$active."/".$entries.$processlist." - maximum: ".$queues."/".$maxqueues, LOGGER_DEBUG);
 694
 695                         // Are there fewer workers running as possible? Then fork a new one.
 696                         if (!Config::get("system", "worker_dont_fork", false) && ($queues > ($active + 1)) && ($entries > 1)) {
 697                                 logger("Active workers: ".$active."/".$queues." Fork a new worker.", LOGGER_DEBUG);
 698                                 if (Config::get('system', 'worker_daemon_mode', false)) {
 699                                         self::IPCSetJobState(true);
 700                                 } else {
 701                                         self::spawnWorker();
 702                                 }
 703                         }
 704                 }
 705
 706                 // if there are too much worker, we don't spawn a new one.
 707                 if (Config::get('system', 'worker_daemon_mode', false) && ($active > $queues)) {
 708                         self::IPCSetJobState(false);
 709                 }
 710
 711                 return $active > $queues;
 712         }
 713
 714         /**
 715          * @brief Returns the number of active worker processes
 716          *
 717          * @return integer Number of active worker processes
 718          */
 719         private static function activeWorkers()
 720         {
 721                 return DBA::count('process', ['command' => 'Worker.php']);
 722         }
 723
 724         /**
 725          * @brief Check if we should pass some slow processes
 726          *
 727          * When the active processes of the highest priority are using more than 2/3
 728          * of all processes, we let pass slower processes.
 729          *
 730          * @param string $highest_priority Returns the currently highest priority
 731          * @return bool We let pass a slower process than $highest_priority
 732          */
 733         private static function passingSlow(&$highest_priority)
 734         {
 735                 $highest_priority = 0;
 736
 737                 $r = DBA::p(
 738                         "SELECT `priority`
 739                                 FROM `process`
 740                                 INNER JOIN `workerqueue` ON `workerqueue`.`pid` = `process`.`pid` AND NOT `done`"
 741                 );
 742
 743                 // No active processes at all? Fine
 744                 if (!DBA::isResult($r)) {
 745                         return false;
 746                 }
 747                 $priorities = [];
 748                 while ($line = DBA::fetch($r)) {
 749                         $priorities[] = $line["priority"];
 750                 }
 751                 DBA::close($r);
 752
 753                 // Should not happen
 754                 if (count($priorities) == 0) {
 755                         return false;
 756                 }
 757                 $highest_priority = min($priorities);
 758
 759                 // The highest process is already the slowest one?
 760                 // Then we quit
 761                 if ($highest_priority == PRIORITY_NEGLIGIBLE) {
 762                         return false;
 763                 }
 764                 $high = 0;
 765                 foreach ($priorities as $priority) {
 766                         if ($priority == $highest_priority) {
 767                                 ++$high;
 768                         }
 769                 }
 770                 logger("Highest priority: ".$highest_priority." Total processes: ".count($priorities)." Count high priority processes: ".$high, LOGGER_DEBUG);
 771                 $passing_slow = (($high/count($priorities)) > (2/3));
 772
 773                 if ($passing_slow) {
 774                         logger("Passing slower processes than priority ".$highest_priority, LOGGER_DEBUG);
 775                 }
 776                 return $passing_slow;
 777         }
 778
 779         /**
 780          * @brief Find and claim the next worker process for us
 781          *
 782          * @param boolean $passing_slow Returns if we had passed low priority processes
 783          * @return boolean Have we found something?
 784          */
 785         private static function findWorkerProcesses(&$passing_slow)
 786         {
 787                 $mypid = getmypid();
 788
 789                 // Check if we should pass some low priority process
 790                 $highest_priority = 0;
 791                 $found = false;
 792                 $passing_slow = false;
 793
 794                 // The higher the number of parallel workers, the more we prefetch to prevent concurring access
 795                 // We decrease the limit with the number of entries left in the queue
 796                 $worker_queues = Config::get("system", "worker_queues", 4);
 797                 $queue_length = Config::get('system', 'worker_fetch_limit', 1);
 798                 $lower_job_limit = $worker_queues * $queue_length * 2;
 799                 $jobs = self::totalEntries();
 800
 801                 // Now do some magic
 802                 $exponent = 2;
 803                 $slope = $queue_length / pow($lower_job_limit, $exponent);
 804                 $limit = min($queue_length, ceil($slope * pow($jobs, $exponent)));
 805
 806                 logger('Total: '.$jobs.' - Maximum: '.$queue_length.' - jobs per queue: '.$limit, LOGGER_DEBUG);
 807                 $ids = [];
 808                 if (self::passingSlow($highest_priority)) {
 809                         // Are there waiting processes with a higher priority than the currently highest?
 810                         $result = DBA::select(
 811                                 'workerqueue',
 812                                 ['id'],
 813                                 ["`executed` <= ? AND `priority` < ? AND NOT `done` AND `next_try` < ?",
 814                                 DBA::NULL_DATETIME, $highest_priority, DateTimeFormat::utcNow()],
 815                                 ['limit' => $limit, 'order' => ['priority', 'created']]
 816                         );
 817
 818                         while ($id = DBA::fetch($result)) {
 819                                 $ids[] = $id["id"];
 820                         }
 821                         DBA::close($result);
 822
 823                         $found = (count($ids) > 0);
 824
 825                         if (!$found) {
 826                                 // Give slower processes some processing time
 827                                 $result = DBA::select(
 828                                         'workerqueue',
 829                                         ['id'],
 830                                         ["`executed` <= ? AND `priority` > ? AND NOT `done` AND `next_try` < ?",
 831                                         DBA::NULL_DATETIME, $highest_priority, DateTimeFormat::utcNow()],
 832                                         ['limit' => $limit, 'order' => ['priority', 'created']]
 833                                 );
 834
 835                                 while ($id = DBA::fetch($result)) {
 836                                         $ids[] = $id["id"];
 837                                 }
 838                                 DBA::close($result);
 839
 840                                 $found = (count($ids) > 0);
 841                                 $passing_slow = $found;
 842                         }
 843                 }
 844
 845                 // If there is no result (or we shouldn't pass lower processes) we check without priority limit
 846                 if (!$found) {
 847                         $result = DBA::select(
 848                                 'workerqueue',
 849                                 ['id'],
 850                                 ["`executed` <= ? AND NOT `done` AND `next_try` < ?",
 851                                 DBA::NULL_DATETIME, DateTimeFormat::utcNow()],
 852                                 ['limit' => $limit, 'order' => ['priority', 'created']]
 853                         );
 854
 855                         while ($id = DBA::fetch($result)) {
 856                                 $ids[] = $id["id"];
 857                         }
 858                         DBA::close($result);
 859
 860                         $found = (count($ids) > 0);
 861                 }
 862
 863                 if ($found) {
 864                         $condition = "`id` IN (".substr(str_repeat("?, ", count($ids)), 0, -2).") AND `pid` = 0 AND NOT `done`";
 865                         array_unshift($ids, $condition);
 866                         DBA::update('workerqueue', ['executed' => DateTimeFormat::utcNow(), 'pid' => $mypid], $ids);
 867                 }
 868
 869                 return $found;
 870         }
 871
 872         /**
 873          * @brief Returns the next worker process
 874          *
 875          * @param boolean $passing_slow Returns if we had passed low priority processes
 876          * @return string SQL statement
 877          */
 878         public static function workerProcess(&$passing_slow)
 879         {
 880                 $stamp = (float)microtime(true);
 881
 882                 // There can already be jobs for us in the queue.
 883                 $r = DBA::select('workerqueue', [], ['pid' => getmypid(), 'done' => false]);
 884                 if (DBA::isResult($r)) {
 885                         self::$db_duration += (microtime(true) - $stamp);
 886                         return DBA::toArray($r);
 887                 }
 888                 DBA::close($r);
 889
 890                 $stamp = (float)microtime(true);
 891                 if (!Lock::acquire('worker_process')) {
 892                         return false;
 893                 }
 894                 self::$lock_duration = (microtime(true) - $stamp);
 895
 896                 $stamp = (float)microtime(true);
 897                 $found = self::findWorkerProcesses($passing_slow);
 898                 self::$db_duration += (microtime(true) - $stamp);
 899
 900                 Lock::release('worker_process');
 901
 902                 if ($found) {
 903                         $r = DBA::select('workerqueue', [], ['pid' => getmypid(), 'done' => false]);
 904                         return DBA::toArray($r);
 905                 }
 906                 return false;
 907         }
 908
 909         /**
 910          * @brief Removes a workerqueue entry from the current process
 911          * @return void
 912          */
 913         public static function unclaimProcess()
 914         {
 915                 $mypid = getmypid();
 916
 917                 DBA::update('workerqueue', ['executed' => DBA::NULL_DATETIME, 'pid' => 0], ['pid' => $mypid, 'done' => false]);
 918         }
 919
 920         /**
 921          * @brief Call the front end worker
 922          * @return void
 923          */
 924         public static function callWorker()
 925         {
 926                 if (!Config::get("system", "frontend_worker")) {
 927                         return;
 928                 }
 929
 930                 $url = System::baseUrl()."/worker";
 931                 Network::fetchUrl($url, false, $redirects, 1);
 932         }
 933
 934         /**
 935          * @brief Call the front end worker if there aren't any active
 936          * @return void
 937          */
 938         public static function executeIfIdle()
 939         {
 940                 if (!Config::get("system", "frontend_worker")) {
 941                         return;
 942                 }
 943
 944                 // Do we have "proc_open"? Then we can fork the worker
 945                 if (function_exists("proc_open")) {
 946                         // When was the last time that we called the worker?
 947                         // Less than one minute? Then we quit
 948                         if ((time() - Config::get("system", "worker_started")) < 60) {
 949                                 return;
 950                         }
 951
 952                         Config::set("system", "worker_started", time());
 953
 954                         // Do we have enough running workers? Then we quit here.
 955                         if (self::tooMuchWorkers()) {
 956                                 // Cleaning dead processes
 957                                 self::killStaleWorkers();
 958                                 Process::deleteInactive();
 959
 960                                 return;
 961                         }
 962
 963                         self::runCron();
 964
 965                         logger('Call worker', LOGGER_DEBUG);
 966                         self::spawnWorker();
 967                         return;
 968                 }
 969
 970                 // We cannot execute background processes.
 971                 // We now run the processes from the frontend.
 972                 // This won't work with long running processes.
 973                 self::runCron();
 974
 975                 self::clearProcesses();
 976
 977                 $workers = self::activeWorkers();
 978
 979                 if ($workers == 0) {
 980                         self::callWorker();
 981                 }
 982         }
 983
 984         /**
 985          * @brief Removes long running worker processes
 986          * @return void
 987          */
 988         public static function clearProcesses()
 989         {
 990                 $timeout = Config::get("system", "frontend_worker_timeout", 10);
 991
 992                 /// @todo We should clean up the corresponding workerqueue entries as well
 993                 $condition = ["`created` < ? AND `command` = 'worker.php'",
 994                                 DateTimeFormat::utc("now - ".$timeout." minutes")];
 995                 DBA::delete('process', $condition);
 996         }
 997
 998         /**
 999          * @brief Runs the cron processes
1000          * @return void
1001          */
1002         private static function runCron()
1003         {
1004                 logger('Add cron entries', LOGGER_DEBUG);
1005
1006                 // Check for spooled items
1007                 self::add(PRIORITY_HIGH, "SpoolPost");
1008
1009                 // Run the cron job that calls all other jobs
1010                 self::add(PRIORITY_MEDIUM, "Cron");
1011
1012                 // Cleaning dead processes
1013                 self::killStaleWorkers();
1014         }
1015
1016         /**
1017          * @brief Spawns a new worker
1018          * @return void
1019          */
1020         public static function spawnWorker($do_cron = false)
1021         {
1022                 $command = 'bin/worker.php';
1023
1024                 $args = ['no_cron' => !$do_cron];
1025
1026                 get_app()->proc_run($command, $args);
1027
1028                 // after spawning we have to remove the flag.
1029                 if (Config::get('system', 'worker_daemon_mode', false)) {
1030                         self::IPCSetJobState(false);
1031                 }
1032         }
1033
1034         /**
1035          * @brief Adds tasks to the worker queue
1036          *
1037          * @param (integer|array) priority or parameter array, strings are deprecated and are ignored
1038          *
1039          * next args are passed as $cmd command line
1040          * or: Worker::add(PRIORITY_HIGH, "Notifier", "drop", $drop_id);
1041          * or: Worker::add(array('priority' => PRIORITY_HIGH, 'dont_fork' => true), "CreateShadowEntry", $post_id);
1042          *
1043          * @note $cmd and string args are surrounded with ""
1044          *
1045          * @hooks 'proc_run'
1046          *      array $arr
1047          *
1048          * @return boolean "false" if proc_run couldn't be executed
1049          */
1050         public static function add($cmd)
1051         {
1052                 $args = func_get_args();
1053
1054                 if (!count($args)) {
1055                         return false;
1056                 }
1057
1058                 $arr = ['args' => $args, 'run_cmd' => true];
1059
1060                 Addon::callHooks("proc_run", $arr);
1061                 if (!$arr['run_cmd'] || !count($args)) {
1062                         return true;
1063                 }
1064
1065                 $priority = PRIORITY_MEDIUM;
1066                 $dont_fork = Config::get("system", "worker_dont_fork", false);
1067                 $created = DateTimeFormat::utcNow();
1068
1069                 $run_parameter = array_shift($args);
1070
1071                 if (is_int($run_parameter)) {
1072                         $priority = $run_parameter;
1073                 } elseif (is_array($run_parameter)) {
1074                         if (isset($run_parameter['priority'])) {
1075                                 $priority = $run_parameter['priority'];
1076                         }
1077                         if (isset($run_parameter['created'])) {
1078                                 $created = $run_parameter['created'];
1079                         }
1080                         if (isset($run_parameter['dont_fork'])) {
1081                                 $dont_fork = $run_parameter['dont_fork'];
1082                         }
1083                 }
1084
1085                 $parameters = json_encode($args);
1086                 $found = DBA::exists('workerqueue', ['parameter' => $parameters, 'done' => false]);
1087
1088                 // Quit if there was a database error - a precaution for the update process to 3.5.3
1089                 if (DBA::errorNo() != 0) {
1090                         return false;
1091                 }
1092
1093                 if (!$found) {
1094                         DBA::insert('workerqueue', ['parameter' => $parameters, 'created' => $created, 'priority' => $priority]);
1095                 }
1096
1097                 // Should we quit and wait for the worker to be called as a cronjob?
1098                 if ($dont_fork) {
1099                         return true;
1100                 }
1101
1102                 // If there is a lock then we don't have to check for too much worker
1103                 if (!Lock::acquire('worker', 0)) {
1104                         return true;
1105                 }
1106
1107                 // If there are already enough workers running, don't fork another one
1108                 $quit = self::tooMuchWorkers();
1109                 Lock::release('worker');
1110
1111                 if ($quit) {
1112                         return true;
1113                 }
1114
1115                 // We tell the daemon that a new job entry exists
1116                 if (Config::get('system', 'worker_daemon_mode', false)) {
1117                         // We don't have to set the IPC flag - this is done in "tooMuchWorkers"
1118                         return true;
1119                 }
1120
1121                 // Now call the worker to execute the jobs that we just added to the queue
1122                 self::spawnWorker();
1123
1124                 return true;
1125         }
1126
1127         /**
1128          * Defers the current worker entry
1129          */
1130         public static function defer()
1131         {
1132                 if (empty(BaseObject::getApp()->queue)) {
1133                         return;
1134                 }
1135
1136                 $queue = BaseObject::getApp()->queue;
1137
1138                 $retrial = $queue['retrial'];
1139                 $id = $queue['id'];
1140
1141                 if ($retrial > 14) {
1142                         logger('Id ' . $id . ' had been tried 14 times. We stop now.', LOGGER_DEBUG);
1143                         return;
1144                 }
1145
1146                 // Calculate the delay until the next trial
1147                 $delay = (($retrial + 3) ** 4) + (rand(1, 30) * ($retrial + 1));
1148                 $next = DateTimeFormat::utc('now + ' . $delay . ' seconds');
1149
1150                 logger('Defer execution ' . $retrial . ' of id ' . $id . ' to ' . $next, LOGGER_DEBUG);
1151
1152                 $fields = ['retrial' => $retrial + 1, 'next_try' => $next, 'executed' => DBA::NULL_DATETIME, 'pid' => 0];
1153                 DBA::update('workerqueue', $fields, ['id' => $id]);
1154         }
1155
1156         /**
1157          * Log active processes into the "process" table
1158          *
1159          * @brief Log active processes into the "process" table
1160          */
1161         public static function startProcess()
1162         {
1163                 $trace = debug_backtrace(DEBUG_BACKTRACE_IGNORE_ARGS, 1);
1164
1165                 $command = basename($trace[0]['file']);
1166
1167                 Process::deleteInactive();
1168
1169                 Process::insert($command);
1170         }
1171
1172         /**
1173          * Remove the active process from the "process" table
1174          *
1175          * @brief Remove the active process from the "process" table
1176          * @return bool
1177          */
1178         public static function endProcess()
1179         {
1180                 return Process::deleteByPid();
1181         }
1182
1183         /**
1184          * Set the flag if some job is waiting
1185          *
1186          * @brief Set the flag if some job is waiting
1187          * @param boolean $jobs Is there a waiting job?
1188          */
1189         public static function IPCSetJobState($jobs)
1190         {
1191                 DBA::update('worker-ipc', ['jobs' => $jobs], ['key' => 1], true);
1192         }
1193
1194         /**
1195          * Checks if some worker job waits to be executed
1196          *
1197          * @brief Checks if some worker job waits to be executed
1198          * @return bool
1199          */
1200         public static function IPCJobsExists()
1201         {
1202                 $row = DBA::selectFirst('worker-ipc', ['jobs'], ['key' => 1]);
1203
1204                 // When we don't have a row, no job is running
1205                 if (!DBA::isResult($row)) {
1206                         return false;
1207                 }
1208
1209                 return (bool)$row['jobs'];
1210         }
1211 }