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\Core\Logger;
   9 use Friendica\Database\DBA;
  10 use Friendica\Model\Process;
  11 use Friendica\Util\DateTimeFormat;
  12 use Friendica\Util\Network;
  13
  14 require_once 'include/dba.php';
  15
  16 /**
  17  * @file src/Core/Worker.php
  18  *
  19  * @brief Contains the class for the worker background job processing
  20  */
  21
  22 /**
  23  * @brief Worker methods
  24  */
  25 class Worker
  26 {
  27         private static $up_start;
  28         private static $db_duration;
  29         private static $last_update;
  30         private static $lock_duration;
  31
  32         /**
  33          * @brief Processes the tasks that are in the workerqueue table
  34          *
  35          * @param boolean $run_cron Should the cron processes be executed?
  36          * @return void
  37          */
  38         public static function processQueue($run_cron = true)
  39         {
  40                 $a = get_app();
  41
  42                 self::$up_start = microtime(true);
  43
  44                 // At first check the maximum load. We shouldn't continue with a high load
  45                 if ($a->isMaxLoadReached()) {
  46                         Logger::log('Pre check: maximum load reached, quitting.', LOGGER_DEBUG);
  47                         return;
  48                 }
  49
  50                 // We now start the process. This is done after the load check since this could increase the load.
  51                 self::startProcess();
  52
  53                 // Kill stale processes every 5 minutes
  54                 $last_cleanup = Config::get('system', 'worker_last_cleaned', 0);
  55                 if (time() > ($last_cleanup + 300)) {
  56                         Config::set('system', 'worker_last_cleaned', time());
  57                         self::killStaleWorkers();
  58                 }
  59
  60                 // Count active workers and compare them with a maximum value that depends on the load
  61                 if (self::tooMuchWorkers()) {
  62                         Logger::log('Pre check: Active worker limit reached, quitting.', LOGGER_DEBUG);
  63                         return;
  64                 }
  65
  66                 // Do we have too few memory?
  67                 if ($a->isMinMemoryReached()) {
  68                         Logger::log('Pre check: Memory limit reached, quitting.', LOGGER_DEBUG);
  69                         return;
  70                 }
  71
  72                 // Possibly there are too much database connections
  73                 if (self::maxConnectionsReached()) {
  74                         Logger::log('Pre check: maximum connections reached, quitting.', LOGGER_DEBUG);
  75                         return;
  76                 }
  77
  78                 // Possibly there are too much database processes that block the system
  79                 if ($a->isMaxProcessesReached()) {
  80                         Logger::log('Pre check: maximum processes reached, quitting.', LOGGER_DEBUG);
  81                         return;
  82                 }
  83
  84                 // Now we start additional cron processes if we should do so
  85                 if ($run_cron) {
  86                         self::runCron();
  87                 }
  88
  89                 $starttime = time();
  90
  91                 // We fetch the next queue entry that is about to be executed
  92                 while ($r = self::workerProcess($passing_slow)) {
  93                         // When we are processing jobs with a lower priority, we don't refetch new jobs
  94                         // Otherwise fast jobs could wait behind slow ones and could be blocked.
  95                         $refetched = $passing_slow;
  96
  97                         foreach ($r as $entry) {
  98                                 // Assure that the priority is an integer value
  99                                 $entry['priority'] = (int)$entry['priority'];
 100
 101                                 // The work will be done
 102                                 if (!self::execute($entry)) {
 103                                         Logger::log('Process execution failed, quitting.', LOGGER_DEBUG);
 104                                         return;
 105                                 }
 106
 107                                 // If possible we will fetch new jobs for this worker
 108                                 if (!$refetched && Lock::acquire('worker_process', 0)) {
 109                                         $stamp = (float)microtime(true);
 110                                         $refetched = self::findWorkerProcesses($passing_slow);
 111                                         self::$db_duration += (microtime(true) - $stamp);
 112                                         Lock::release('worker_process');
 113                                 }
 114                         }
 115
 116                         // To avoid the quitting of multiple workers only one worker at a time will execute the check
 117                         if (Lock::acquire('worker', 0)) {
 118                                 $stamp = (float)microtime(true);
 119                                 // Count active workers and compare them with a maximum value that depends on the load
 120                                 if (self::tooMuchWorkers()) {
 121                                         Logger::log('Active worker limit reached, quitting.', LOGGER_DEBUG);
 122                                         Lock::release('worker');
 123                                         return;
 124                                 }
 125
 126                                 // Check free memory
 127                                 if ($a->isMinMemoryReached()) {
 128                                         Logger::log('Memory limit reached, quitting.', LOGGER_DEBUG);
 129                                         Lock::release('worker');
 130                                         return;
 131                                 }
 132                                 Lock::release('worker');
 133                                 self::$db_duration += (microtime(true) - $stamp);
 134                         }
 135
 136                         // Quit the worker once every 5 minutes
 137                         if (time() > ($starttime + 300)) {
 138                                 Logger::log('Process lifetime reached, quitting.', LOGGER_DEBUG);
 139                                 return;
 140                         }
 141                 }
 142
 143                 // Cleaning up. Possibly not needed, but it doesn't harm anything.
 144                 if (Config::get('system', 'worker_daemon_mode', false)) {
 145                         self::IPCSetJobState(false);
 146                 }
 147                 Logger::log("Couldn't select a workerqueue entry, quitting process " . getmypid() . ".", LOGGER_DEBUG);
 148         }
 149
 150         /**
 151          * @brief Returns the number of deferred entries in the worker queue
 152          *
 153          * @return integer Number of deferred entries in the worker queue
 154          */
 155         private static function deferredEntries()
 156         {
 157                 return DBA::count('workerqueue', ["`executed` <= ? AND NOT `done` AND `next_try` > ?",
 158                         DBA::NULL_DATETIME, DateTimeFormat::utcNow()]);
 159         }
 160
 161         /**
 162          * @brief Returns the number of non executed entries in the worker queue
 163          *
 164          * @return integer Number of non executed entries in the worker queue
 165          */
 166         private static function totalEntries()
 167         {
 168                 return DBA::count('workerqueue', ["`executed` <= ? AND NOT `done` AND `next_try` < ?",
 169                         DBA::NULL_DATETIME, DateTimeFormat::utcNow()]);
 170         }
 171
 172         /**
 173          * @brief Returns the highest priority in the worker queue that isn't executed
 174          *
 175          * @return integer Number of active worker processes
 176          */
 177         private static function highestPriority()
 178         {
 179                 $condition = ["`executed` <= ? AND NOT `done` AND `next_try` < ?", DBA::NULL_DATETIME, DateTimeFormat::utcNow()];
 180                 $workerqueue = DBA::selectFirst('workerqueue', ['priority'], $condition, ['order' => ['priority']]);
 181                 if (DBA::isResult($workerqueue)) {
 182                         return $workerqueue["priority"];
 183                 } else {
 184                         return 0;
 185                 }
 186         }
 187
 188         /**
 189          * @brief Returns if a process with the given priority is running
 190          *
 191          * @param integer $priority The priority that should be checked
 192          *
 193          * @return integer Is there a process running with that priority?
 194          */
 195         private static function processWithPriorityActive($priority)
 196         {
 197                 $condition = ["`priority` <= ? AND `executed` > ? AND NOT `done` AND `next_try` < ?",
 198                         $priority, DBA::NULL_DATETIME, DateTimeFormat::utcNow()];
 199                 return DBA::exists('workerqueue', $condition);
 200         }
 201
 202         /**
 203          * @brief Execute a worker entry
 204          *
 205          * @param array $queue Workerqueue entry
 206          *
 207          * @return boolean "true" if further processing should be stopped
 208          */
 209         public static function execute($queue)
 210         {
 211                 $a = get_app();
 212
 213                 $mypid = getmypid();
 214
 215                 // Quit when in maintenance
 216                 if (Config::get('system', 'maintenance', false, true)) {
 217                         Logger::log("Maintenance mode - quit process ".$mypid, LOGGER_DEBUG);
 218                         return false;
 219                 }
 220
 221                 // Constantly check the number of parallel database processes
 222                 if ($a->isMaxProcessesReached()) {
 223                         Logger::log("Max processes reached for process ".$mypid, LOGGER_DEBUG);
 224                         return false;
 225                 }
 226
 227                 // Constantly check the number of available database connections to let the frontend be accessible at any time
 228                 if (self::maxConnectionsReached()) {
 229                         Logger::log("Max connection reached for process ".$mypid, LOGGER_DEBUG);
 230                         return false;
 231                 }
 232
 233                 $argv = json_decode($queue["parameter"], true);
 234
 235                 // Check for existance and validity of the include file
 236                 $include = $argv[0];
 237
 238                 if (method_exists(sprintf('Friendica\Worker\%s', $include), 'execute')) {
 239                         // We constantly update the "executed" date every minute to avoid being killed too soon
 240                         if (!isset(self::$last_update)) {
 241                                 self::$last_update = strtotime($queue["executed"]);
 242                         }
 243
 244                         $age = (time() - self::$last_update) / 60;
 245                         self::$last_update = time();
 246
 247                         if ($age > 1) {
 248                                 $stamp = (float)microtime(true);
 249                                 DBA::update('workerqueue', ['executed' => DateTimeFormat::utcNow()], ['pid' => $mypid, 'done' => false]);
 250                                 self::$db_duration += (microtime(true) - $stamp);
 251                         }
 252
 253                         array_shift($argv);
 254
 255                         self::execFunction($queue, $include, $argv, true);
 256
 257                         $stamp = (float)microtime(true);
 258
 259                         $condition = ["`id` = ? AND `next_try` < ?", $queue['id'], DateTimeFormat::utcNow()];
 260                         if (DBA::update('workerqueue', ['done' => true], $condition)) {
 261                                 Config::set('system', 'last_worker_execution', DateTimeFormat::utcNow());
 262                         }
 263                         self::$db_duration = (microtime(true) - $stamp);
 264
 265                         return true;
 266                 }
 267
 268                 // The script could be provided as full path or only with the function name
 269                 if ($include == basename($include)) {
 270                         $include = "include/".$include.".php";
 271                 }
 272
 273                 if (!validate_include($include)) {
 274                         Logger::log("Include file ".$argv[0]." is not valid!");
 275                         DBA::delete('workerqueue', ['id' => $queue["id"]]);
 276                         return true;
 277                 }
 278
 279                 require_once $include;
 280
 281                 $funcname = str_replace(".php", "", basename($argv[0]))."_run";
 282
 283                 if (function_exists($funcname)) {
 284                         // We constantly update the "executed" date every minute to avoid being killed too soon
 285                         if (!isset(self::$last_update)) {
 286                                 self::$last_update = strtotime($queue["executed"]);
 287                         }
 288
 289                         $age = (time() - self::$last_update) / 60;
 290                         self::$last_update = time();
 291
 292                         if ($age > 1) {
 293                                 $stamp = (float)microtime(true);
 294                                 DBA::update('workerqueue', ['executed' => DateTimeFormat::utcNow()], ['pid' => $mypid, 'done' => false]);
 295                                 self::$db_duration += (microtime(true) - $stamp);
 296                         }
 297
 298                         self::execFunction($queue, $funcname, $argv, false);
 299
 300                         $stamp = (float)microtime(true);
 301                         if (DBA::update('workerqueue', ['done' => true], ['id' => $queue["id"]])) {
 302                                 Config::set('system', 'last_worker_execution', DateTimeFormat::utcNow());
 303                         }
 304                         self::$db_duration = (microtime(true) - $stamp);
 305                 } else {
 306                         Logger::log("Function ".$funcname." does not exist");
 307                         DBA::delete('workerqueue', ['id' => $queue["id"]]);
 308                 }
 309
 310                 return true;
 311         }
 312
 313         /**
 314          * @brief Execute a function from the queue
 315          *
 316          * @param array   $queue       Workerqueue entry
 317          * @param string  $funcname    name of the function
 318          * @param array   $argv        Array of values to be passed to the function
 319          * @param boolean $method_call boolean
 320          * @return void
 321          */
 322         private static function execFunction($queue, $funcname, $argv, $method_call)
 323         {
 324                 $a = get_app();
 325
 326                 $mypid = getmypid();
 327
 328                 $argc = count($argv);
 329
 330                 $new_process_id = System::processID("wrk");
 331
 332                 Logger::log("Process ".$mypid." - Prio ".$queue["priority"]." - ID ".$queue["id"].": ".$funcname." ".$queue["parameter"]." - Process PID: ".$new_process_id);
 333
 334                 $stamp = (float)microtime(true);
 335
 336                 // We use the callstack here to analyze the performance of executed worker entries.
 337                 // For this reason the variables have to be initialized.
 338                 if (Config::get("system", "profiler")) {
 339                         $a->performance["start"] = microtime(true);
 340                         $a->performance["database"] = 0;
 341                         $a->performance["database_write"] = 0;
 342                         $a->performance["cache"] = 0;
 343                         $a->performance["cache_write"] = 0;
 344                         $a->performance["network"] = 0;
 345                         $a->performance["file"] = 0;
 346                         $a->performance["rendering"] = 0;
 347                         $a->performance["parser"] = 0;
 348                         $a->performance["marktime"] = 0;
 349                         $a->performance["markstart"] = microtime(true);
 350                         $a->callstack = [];
 351                 }
 352
 353                 // For better logging create a new process id for every worker call
 354                 // But preserve the old one for the worker
 355                 $old_process_id = $a->process_id;
 356                 $a->process_id = $new_process_id;
 357                 $a->queue = $queue;
 358
 359                 $up_duration = number_format(microtime(true) - self::$up_start, 3);
 360
 361                 // Reset global data to avoid interferences
 362                 unset($_SESSION);
 363
 364                 if ($method_call) {
 365                         call_user_func_array(sprintf('Friendica\Worker\%s::execute', $funcname), $argv);
 366                 } else {
 367                         $funcname($argv, $argc);
 368                 }
 369
 370                 $a->process_id = $old_process_id;
 371                 unset($a->queue);
 372
 373                 $duration = (microtime(true) - $stamp);
 374
 375                 self::$up_start = microtime(true);
 376
 377                 /* With these values we can analyze how effective the worker is.
 378                  * The database and rest time should be low since this is the unproductive time.
 379                  * The execution time is the productive time.
 380                  * By changing parameters like the maximum number of workers we can check the effectivness.
 381                 */
 382                 Logger::log(
 383                         'DB: '.number_format(self::$db_duration, 2).
 384                         ' - Lock: '.number_format(self::$lock_duration, 2).
 385                         ' - Rest: '.number_format($up_duration - self::$db_duration - self::$lock_duration, 2).
 386                         ' - Execution: '.number_format($duration, 2),
 387                         LOGGER_DEBUG
 388                 );
 389
 390                 self::$lock_duration = 0;
 391
 392                 if ($duration > 3600) {
 393                         Logger::log("Prio ".$queue["priority"].": ".$queue["parameter"]." - longer than 1 hour (".round($duration/60, 3).")", LOGGER_DEBUG);
 394                 } elseif ($duration > 600) {
 395                         Logger::log("Prio ".$queue["priority"].": ".$queue["parameter"]." - longer than 10 minutes (".round($duration/60, 3).")", LOGGER_DEBUG);
 396                 } elseif ($duration > 300) {
 397                         Logger::log("Prio ".$queue["priority"].": ".$queue["parameter"]." - longer than 5 minutes (".round($duration/60, 3).")", LOGGER_DEBUG);
 398                 } elseif ($duration > 120) {
 399                         Logger::log("Prio ".$queue["priority"].": ".$queue["parameter"]." - longer than 2 minutes (".round($duration/60, 3).")", LOGGER_DEBUG);
 400                 }
 401
 402                 Logger::log("Process ".$mypid." - Prio ".$queue["priority"]." - ID ".$queue["id"].": ".$funcname." - done in ".$duration." seconds. Process PID: ".$new_process_id);
 403
 404                 // Write down the performance values into the log
 405                 if (Config::get("system", "profiler")) {
 406                         $duration = microtime(true)-$a->performance["start"];
 407
 408                         $o = '';
 409                         if (Config::get("rendertime", "callstack")) {
 410                                 if (isset($a->callstack["database"])) {
 411                                         $o .= "\nDatabase Read:\n";
 412                                         foreach ($a->callstack["database"] as $func => $time) {
 413                                                 $time = round($time, 3);
 414                                                 if ($time > 0) {
 415                                                         $o .= $func.": ".$time."\n";
 416                                                 }
 417                                         }
 418                                 }
 419                                 if (isset($a->callstack["database_write"])) {
 420                                         $o .= "\nDatabase Write:\n";
 421                                         foreach ($a->callstack["database_write"] as $func => $time) {
 422                                                 $time = round($time, 3);
 423                                                 if ($time > 0) {
 424                                                         $o .= $func.": ".$time."\n";
 425                                                 }
 426                                         }
 427                                 }
 428                                 if (isset($a->callstack["dache"])) {
 429                                         $o .= "\nCache Read:\n";
 430                                         foreach ($a->callstack["dache"] as $func => $time) {
 431                                                 $time = round($time, 3);
 432                                                 if ($time > 0) {
 433                                                         $o .= $func.": ".$time."\n";
 434                                                 }
 435                                         }
 436                                 }
 437                                 if (isset($a->callstack["dache_write"])) {
 438                                         $o .= "\nCache Write:\n";
 439                                         foreach ($a->callstack["dache_write"] as $func => $time) {
 440                                                 $time = round($time, 3);
 441                                                 if ($time > 0) {
 442                                                         $o .= $func.": ".$time."\n";
 443                                                 }
 444                                         }
 445                                 }
 446                                 if (isset($a->callstack["network"])) {
 447                                         $o .= "\nNetwork:\n";
 448                                         foreach ($a->callstack["network"] as $func => $time) {
 449                                                 $time = round($time, 3);
 450                                                 if ($time > 0) {
 451                                                         $o .= $func.": ".$time."\n";
 452                                                 }
 453                                         }
 454                                 }
 455                         }
 456
 457                         Logger::log(
 458                                 "ID ".$queue["id"].": ".$funcname.": ".sprintf(
 459                                         "DB: %s/%s, Cache: %s/%s, Net: %s, I/O: %s, Other: %s, Total: %s".$o,
 460                                         number_format($a->performance["database"] - $a->performance["database_write"], 2),
 461                                         number_format($a->performance["database_write"], 2),
 462                                         number_format($a->performance["cache"], 2),
 463                                         number_format($a->performance["cache_write"], 2),
 464                                         number_format($a->performance["network"], 2),
 465                                         number_format($a->performance["file"], 2),
 466                                         number_format($duration - ($a->performance["database"]
 467                                                 + $a->performance["cache"] + $a->performance["cache_write"]
 468                                                 + $a->performance["network"] + $a->performance["file"]), 2),
 469                                         number_format($duration, 2)
 470                                 ),
 471                                 LOGGER_DEBUG
 472                         );
 473                 }
 474
 475                 $cooldown = Config::get("system", "worker_cooldown", 0);
 476
 477                 if ($cooldown > 0) {
 478                         Logger::log("Process ".$mypid." - Prio ".$queue["priority"]." - ID ".$queue["id"].": ".$funcname." - in cooldown for ".$cooldown." seconds");
 479                         sleep($cooldown);
 480                 }
 481         }
 482
 483         /**
 484          * @brief Checks if the number of database connections has reached a critical limit.
 485          *
 486          * @return bool Are more than 3/4 of the maximum connections used?
 487          */
 488         private static function maxConnectionsReached()
 489         {
 490                 // Fetch the max value from the config. This is needed when the system cannot detect the correct value by itself.
 491                 $max = Config::get("system", "max_connections");
 492
 493                 // Fetch the percentage level where the worker will get active
 494                 $maxlevel = Config::get("system", "max_connections_level", 75);
 495
 496                 if ($max == 0) {
 497                         // the maximum number of possible user connections can be a system variable
 498                         $r = DBA::fetchFirst("SHOW VARIABLES WHERE `variable_name` = 'max_user_connections'");
 499                         if (DBA::isResult($r)) {
 500                                 $max = $r["Value"];
 501                         }
 502                         // Or it can be granted. This overrides the system variable
 503                         $r = DBA::p('SHOW GRANTS');
 504                         while ($grants = DBA::fetch($r)) {
 505                                 $grant = array_pop($grants);
 506                                 if (stristr($grant, "GRANT USAGE ON")) {
 507                                         if (preg_match("/WITH MAX_USER_CONNECTIONS (\d*)/", $grant, $match)) {
 508                                                 $max = $match[1];
 509                                         }
 510                                 }
 511                         }
 512                         DBA::close($r);
 513                 }
 514
 515                 // If $max is set we will use the processlist to determine the current number of connections
 516                 // The processlist only shows entries of the current user
 517                 if ($max != 0) {
 518                         $r = DBA::p('SHOW PROCESSLIST');
 519                         $used = DBA::numRows($r);
 520                         DBA::close($r);
 521
 522                         Logger::log("Connection usage (user values): ".$used."/".$max, LOGGER_DEBUG);
 523
 524                         $level = ($used / $max) * 100;
 525
 526                         if ($level >= $maxlevel) {
 527                                 Logger::log("Maximum level (".$maxlevel."%) of user connections reached: ".$used."/".$max);
 528                                 return true;
 529                         }
 530                 }
 531
 532                 // We will now check for the system values.
 533                 // This limit could be reached although the user limits are fine.
 534                 $r = DBA::fetchFirst("SHOW VARIABLES WHERE `variable_name` = 'max_connections'");
 535                 if (!DBA::isResult($r)) {
 536                         return false;
 537                 }
 538                 $max = intval($r["Value"]);
 539                 if ($max == 0) {
 540                         return false;
 541                 }
 542                 $r = DBA::fetchFirst("SHOW STATUS WHERE `variable_name` = 'Threads_connected'");
 543                 if (!DBA::isResult($r)) {
 544                         return false;
 545                 }
 546                 $used = intval($r["Value"]);
 547                 if ($used == 0) {
 548                         return false;
 549                 }
 550                 Logger::log("Connection usage (system values): ".$used."/".$max, LOGGER_DEBUG);
 551
 552                 $level = $used / $max * 100;
 553
 554                 if ($level < $maxlevel) {
 555                         return false;
 556                 }
 557                 Logger::log("Maximum level (".$level."%) of system connections reached: ".$used."/".$max);
 558                 return true;
 559         }
 560
 561         /**
 562          * @brief fix the queue entry if the worker process died
 563          * @return void
 564          */
 565         private static function killStaleWorkers()
 566         {
 567                 $entries = DBA::select(
 568                         'workerqueue',
 569                         ['id', 'pid', 'executed', 'priority', 'parameter'],
 570                         ['`executed` > ? AND NOT `done` AND `pid` != 0', DBA::NULL_DATETIME],
 571                         ['order' => ['priority', 'created']]
 572                 );
 573
 574                 while ($entry = DBA::fetch($entries)) {
 575                         if (!posix_kill($entry["pid"], 0)) {
 576                                 DBA::update(
 577                                         'workerqueue',
 578                                         ['executed' => DBA::NULL_DATETIME, 'pid' => 0],
 579                                         ['id' => $entry["id"]]
 580                                 );
 581                         } else {
 582                                 // Kill long running processes
 583                                 // Check if the priority is in a valid range
 584                                 if (!in_array($entry["priority"], [PRIORITY_CRITICAL, PRIORITY_HIGH, PRIORITY_MEDIUM, PRIORITY_LOW, PRIORITY_NEGLIGIBLE])) {
 585                                         $entry["priority"] = PRIORITY_MEDIUM;
 586                                 }
 587
 588                                 // Define the maximum durations
 589                                 $max_duration_defaults = [PRIORITY_CRITICAL => 720, PRIORITY_HIGH => 10, PRIORITY_MEDIUM => 60, PRIORITY_LOW => 180, PRIORITY_NEGLIGIBLE => 720];
 590                                 $max_duration = $max_duration_defaults[$entry["priority"]];
 591
 592                                 $argv = json_decode($entry["parameter"], true);
 593                                 $argv[0] = basename($argv[0]);
 594
 595                                 // How long is the process already running?
 596                                 $duration = (time() - strtotime($entry["executed"])) / 60;
 597                                 if ($duration > $max_duration) {
 598                                         Logger::log("Worker process ".$entry["pid"]." (".substr(json_encode($argv), 0, 50).") took more than ".$max_duration." minutes. It will be killed now.");
 599                                         posix_kill($entry["pid"], SIGTERM);
 600
 601                                         // We killed the stale process.
 602                                         // To avoid a blocking situation we reschedule the process at the beginning of the queue.
 603                                         // Additionally we are lowering the priority. (But not PRIORITY_CRITICAL)
 604                                         $new_priority = $entry["priority"];
 605                                         if ($entry["priority"] == PRIORITY_HIGH) {
 606                                                 $new_priority = PRIORITY_MEDIUM;
 607                                         } elseif ($entry["priority"] == PRIORITY_MEDIUM) {
 608                                                 $new_priority = PRIORITY_LOW;
 609                                         } elseif ($entry["priority"] != PRIORITY_CRITICAL) {
 610                                                 $new_priority = PRIORITY_NEGLIGIBLE;
 611                                         }
 612                                         DBA::update(
 613                                                 'workerqueue',
 614                                                 ['executed' => DBA::NULL_DATETIME, 'created' => DateTimeFormat::utcNow(), 'priority' => $new_priority, 'pid' => 0],
 615                                                 ['id' => $entry["id"]]
 616                                         );
 617                                 } else {
 618                                         Logger::log("Worker process ".$entry["pid"]." (".substr(json_encode($argv), 0, 50).") now runs for ".round($duration)." of ".$max_duration." allowed minutes. That's okay.", LOGGER_DEBUG);
 619                                 }
 620                         }
 621                 }
 622         }
 623
 624         /**
 625          * @brief Checks if the number of active workers exceeds the given limits
 626          *
 627          * @return bool Are there too much workers running?
 628          */
 629         public static function tooMuchWorkers()
 630         {
 631                 $queues = Config::get("system", "worker_queues", 4);
 632
 633                 $maxqueues = $queues;
 634
 635                 $active = self::activeWorkers();
 636
 637                 // Decrease the number of workers at higher load
 638                 $load = System::currentLoad();
 639                 if ($load) {
 640                         $maxsysload = intval(Config::get("system", "maxloadavg", 50));
 641
 642                         /* Default exponent 3 causes queues to rapidly decrease as load increases.
 643                          * If you have 20 max queues at idle, then you get only 5 queues at 37.1% of $maxsysload.
 644                          * For some environments, this rapid decrease is not needed.
 645                          * With exponent 1, you could have 20 max queues at idle and 13 at 37% of $maxsysload.
 646                          */
 647                         $exponent = intval(Config::get('system', 'worker_load_exponent', 3));
 648                         $slope = pow(max(0, $maxsysload - $load) / $maxsysload, $exponent);
 649                         $queues = intval(ceil($slope * $maxqueues));
 650
 651                         $processlist = '';
 652
 653                         if (Config::get('system', 'worker_debug')) {
 654                                 // Create a list of queue entries grouped by their priority
 655                                 $listitem = [];
 656
 657                                 // Adding all processes with no workerqueue entry
 658                                 $processes = DBA::p(
 659                                         "SELECT COUNT(*) AS `running` FROM `process` WHERE NOT EXISTS
 660                                                         (SELECT id FROM `workerqueue`
 661                                                         WHERE `workerqueue`.`pid` = `process`.`pid` AND NOT `done` AND `pid` != ?)",
 662                                         getmypid()
 663                                 );
 664
 665                                 if ($process = DBA::fetch($processes)) {
 666                                         $listitem[0] = "0:".$process["running"];
 667                                 }
 668                                 DBA::close($processes);
 669
 670                                 // Now adding all processes with workerqueue entries
 671                                 $entries = DBA::p("SELECT COUNT(*) AS `entries`, `priority` FROM `workerqueue` WHERE NOT `done` GROUP BY `priority`");
 672                                 while ($entry = DBA::fetch($entries)) {
 673                                         $processes = DBA::p("SELECT COUNT(*) AS `running` FROM `process` INNER JOIN `workerqueue` ON `workerqueue`.`pid` = `process`.`pid` AND NOT `done` WHERE `priority` = ?", $entry["priority"]);
 674                                         if ($process = DBA::fetch($processes)) {
 675                                                 $listitem[$entry["priority"]] = $entry["priority"].":".$process["running"]."/".$entry["entries"];
 676                                         }
 677                                         DBA::close($processes);
 678                                 }
 679                                 DBA::close($entries);
 680
 681                                 $intervals = [1, 10, 60];
 682                                 $jobs_per_minute = [];
 683                                 foreach ($intervals as $interval) {
 684                                         $jobs = DBA::p("SELECT COUNT(*) AS `jobs` FROM `workerqueue` WHERE `done` AND `executed` > UTC_TIMESTAMP() - INTERVAL ".intval($interval)." MINUTE");
 685                                         if ($job = DBA::fetch($jobs)) {
 686                                                 $jobs_per_minute[$interval] = number_format($job['jobs'] / $interval, 0);
 687                                         }
 688                                         DBA::close($jobs);
 689                                 }
 690                                 $processlist = ' - jpm: '.implode('/', $jobs_per_minute).' ('.implode(', ', $listitem).')';
 691                         }
 692
 693                         $entries = self::totalEntries();
 694                         $deferred = self::deferredEntries();
 695
 696                         if (Config::get("system", "worker_fastlane", false) && ($queues > 0) && ($entries > 0) && ($active >= $queues)) {
 697                                 $top_priority = self::highestPriority();
 698                                 $high_running = self::processWithPriorityActive($top_priority);
 699
 700                                 if (!$high_running && ($top_priority > PRIORITY_UNDEFINED) && ($top_priority < PRIORITY_NEGLIGIBLE)) {
 701                                         Logger::log("There are jobs with priority ".$top_priority." waiting but none is executed. Open a fastlane.", LOGGER_DEBUG);
 702                                         $queues = $active + 1;
 703                                 }
 704                         }
 705
 706                         Logger::log("Load: " . $load ."/" . $maxsysload . " - processes: " . $deferred . "/" . $active . "/" . $entries . $processlist . " - maximum: " . $queues . "/" . $maxqueues, LOGGER_DEBUG);
 707
 708                         // Are there fewer workers running as possible? Then fork a new one.
 709                         if (!Config::get("system", "worker_dont_fork", false) && ($queues > ($active + 1)) && ($entries > 1)) {
 710                                 Logger::log("Active workers: ".$active."/".$queues." Fork a new worker.", LOGGER_DEBUG);
 711                                 if (Config::get('system', 'worker_daemon_mode', false)) {
 712                                         self::IPCSetJobState(true);
 713                                 } else {
 714                                         self::spawnWorker();
 715                                 }
 716                         }
 717                 }
 718
 719                 // if there are too much worker, we don't spawn a new one.
 720                 if (Config::get('system', 'worker_daemon_mode', false) && ($active > $queues)) {
 721                         self::IPCSetJobState(false);
 722                 }
 723
 724                 return $active > $queues;
 725         }
 726
 727         /**
 728          * @brief Returns the number of active worker processes
 729          *
 730          * @return integer Number of active worker processes
 731          */
 732         private static function activeWorkers()
 733         {
 734                 return DBA::count('process', ['command' => 'Worker.php']);
 735         }
 736
 737         /**
 738          * @brief Check if we should pass some slow processes
 739          *
 740          * When the active processes of the highest priority are using more than 2/3
 741          * of all processes, we let pass slower processes.
 742          *
 743          * @param string $highest_priority Returns the currently highest priority
 744          * @return bool We let pass a slower process than $highest_priority
 745          */
 746         private static function passingSlow(&$highest_priority)
 747         {
 748                 $highest_priority = 0;
 749
 750                 $r = DBA::p(
 751                         "SELECT `priority`
 752                                 FROM `process`
 753                                 INNER JOIN `workerqueue` ON `workerqueue`.`pid` = `process`.`pid` AND NOT `done`"
 754                 );
 755
 756                 // No active processes at all? Fine
 757                 if (!DBA::isResult($r)) {
 758                         return false;
 759                 }
 760                 $priorities = [];
 761                 while ($line = DBA::fetch($r)) {
 762                         $priorities[] = $line["priority"];
 763                 }
 764                 DBA::close($r);
 765
 766                 // Should not happen
 767                 if (count($priorities) == 0) {
 768                         return false;
 769                 }
 770                 $highest_priority = min($priorities);
 771
 772                 // The highest process is already the slowest one?
 773                 // Then we quit
 774                 if ($highest_priority == PRIORITY_NEGLIGIBLE) {
 775                         return false;
 776                 }
 777                 $high = 0;
 778                 foreach ($priorities as $priority) {
 779                         if ($priority == $highest_priority) {
 780                                 ++$high;
 781                         }
 782                 }
 783                 Logger::log("Highest priority: ".$highest_priority." Total processes: ".count($priorities)." Count high priority processes: ".$high, LOGGER_DEBUG);
 784                 $passing_slow = (($high/count($priorities)) > (2/3));
 785
 786                 if ($passing_slow) {
 787                         Logger::log("Passing slower processes than priority ".$highest_priority, LOGGER_DEBUG);
 788                 }
 789                 return $passing_slow;
 790         }
 791
 792         /**
 793          * @brief Find and claim the next worker process for us
 794          *
 795          * @param boolean $passing_slow Returns if we had passed low priority processes
 796          * @return boolean Have we found something?
 797          */
 798         private static function findWorkerProcesses(&$passing_slow)
 799         {
 800                 $mypid = getmypid();
 801
 802                 // Check if we should pass some low priority process
 803                 $highest_priority = 0;
 804                 $found = false;
 805                 $passing_slow = false;
 806
 807                 // The higher the number of parallel workers, the more we prefetch to prevent concurring access
 808                 // We decrease the limit with the number of entries left in the queue
 809                 $worker_queues = Config::get("system", "worker_queues", 4);
 810                 $queue_length = Config::get('system', 'worker_fetch_limit', 1);
 811                 $lower_job_limit = $worker_queues * $queue_length * 2;
 812                 $jobs = self::totalEntries();
 813                 $deferred = self::deferredEntries();
 814
 815                 // Now do some magic
 816                 $exponent = 2;
 817                 $slope = $queue_length / pow($lower_job_limit, $exponent);
 818                 $limit = min($queue_length, ceil($slope * pow($jobs, $exponent)));
 819
 820                 Logger::log('Deferred: ' . $deferred . ' - Total: ' . $jobs . ' - Maximum: ' . $queue_length . ' - jobs per queue: ' . $limit, LOGGER_DEBUG);
 821                 $ids = [];
 822                 if (self::passingSlow($highest_priority)) {
 823                         // Are there waiting processes with a higher priority than the currently highest?
 824                         $result = DBA::select(
 825                                 'workerqueue',
 826                                 ['id'],
 827                                 ["`executed` <= ? AND `priority` < ? AND NOT `done` AND `next_try` < ?",
 828                                 DBA::NULL_DATETIME, $highest_priority, DateTimeFormat::utcNow()],
 829                                 ['limit' => $limit, 'order' => ['priority', 'created']]
 830                         );
 831
 832                         while ($id = DBA::fetch($result)) {
 833                                 $ids[] = $id["id"];
 834                         }
 835                         DBA::close($result);
 836
 837                         $found = (count($ids) > 0);
 838
 839                         if (!$found) {
 840                                 // Give slower processes some processing time
 841                                 $result = DBA::select(
 842                                         'workerqueue',
 843                                         ['id'],
 844                                         ["`executed` <= ? AND `priority` > ? AND NOT `done` AND `next_try` < ?",
 845                                         DBA::NULL_DATETIME, $highest_priority, DateTimeFormat::utcNow()],
 846                                         ['limit' => $limit, 'order' => ['priority', 'created']]
 847                                 );
 848
 849                                 while ($id = DBA::fetch($result)) {
 850                                         $ids[] = $id["id"];
 851                                 }
 852                                 DBA::close($result);
 853
 854                                 $found = (count($ids) > 0);
 855                                 $passing_slow = $found;
 856                         }
 857                 }
 858
 859                 // If there is no result (or we shouldn't pass lower processes) we check without priority limit
 860                 if (!$found) {
 861                         $result = DBA::select(
 862                                 'workerqueue',
 863                                 ['id'],
 864                                 ["`executed` <= ? AND NOT `done` AND `next_try` < ?",
 865                                 DBA::NULL_DATETIME, DateTimeFormat::utcNow()],
 866                                 ['limit' => $limit, 'order' => ['priority', 'created']]
 867                         );
 868
 869                         while ($id = DBA::fetch($result)) {
 870                                 $ids[] = $id["id"];
 871                         }
 872                         DBA::close($result);
 873
 874                         $found = (count($ids) > 0);
 875                 }
 876
 877                 if ($found) {
 878                         $condition = "`id` IN (".substr(str_repeat("?, ", count($ids)), 0, -2).") AND `pid` = 0 AND NOT `done`";
 879                         array_unshift($ids, $condition);
 880                         DBA::update('workerqueue', ['executed' => DateTimeFormat::utcNow(), 'pid' => $mypid], $ids);
 881                 }
 882
 883                 return $found;
 884         }
 885
 886         /**
 887          * @brief Returns the next worker process
 888          *
 889          * @param boolean $passing_slow Returns if we had passed low priority processes
 890          * @return string SQL statement
 891          */
 892         public static function workerProcess(&$passing_slow)
 893         {
 894                 $stamp = (float)microtime(true);
 895
 896                 // There can already be jobs for us in the queue.
 897                 $r = DBA::select('workerqueue', [], ['pid' => getmypid(), 'done' => false]);
 898                 if (DBA::isResult($r)) {
 899                         self::$db_duration += (microtime(true) - $stamp);
 900                         return DBA::toArray($r);
 901                 }
 902                 DBA::close($r);
 903
 904                 $stamp = (float)microtime(true);
 905                 if (!Lock::acquire('worker_process')) {
 906                         return false;
 907                 }
 908                 self::$lock_duration = (microtime(true) - $stamp);
 909
 910                 $stamp = (float)microtime(true);
 911                 $found = self::findWorkerProcesses($passing_slow);
 912                 self::$db_duration += (microtime(true) - $stamp);
 913
 914                 Lock::release('worker_process');
 915
 916                 if ($found) {
 917                         $r = DBA::select('workerqueue', [], ['pid' => getmypid(), 'done' => false]);
 918                         return DBA::toArray($r);
 919                 }
 920                 return false;
 921         }
 922
 923         /**
 924          * @brief Removes a workerqueue entry from the current process
 925          * @return void
 926          */
 927         public static function unclaimProcess()
 928         {
 929                 $mypid = getmypid();
 930
 931                 DBA::update('workerqueue', ['executed' => DBA::NULL_DATETIME, 'pid' => 0], ['pid' => $mypid, 'done' => false]);
 932         }
 933
 934         /**
 935          * @brief Call the front end worker
 936          * @return void
 937          */
 938         public static function callWorker()
 939         {
 940                 if (!Config::get("system", "frontend_worker")) {
 941                         return;
 942                 }
 943
 944                 $url = System::baseUrl()."/worker";
 945                 Network::fetchUrl($url, false, $redirects, 1);
 946         }
 947
 948         /**
 949          * @brief Call the front end worker if there aren't any active
 950          * @return void
 951          */
 952         public static function executeIfIdle()
 953         {
 954                 if (!Config::get("system", "frontend_worker")) {
 955                         return;
 956                 }
 957
 958                 // Do we have "proc_open"? Then we can fork the worker
 959                 if (function_exists("proc_open")) {
 960                         // When was the last time that we called the worker?
 961                         // Less than one minute? Then we quit
 962                         if ((time() - Config::get("system", "worker_started")) < 60) {
 963                                 return;
 964                         }
 965
 966                         Config::set("system", "worker_started", time());
 967
 968                         // Do we have enough running workers? Then we quit here.
 969                         if (self::tooMuchWorkers()) {
 970                                 // Cleaning dead processes
 971                                 self::killStaleWorkers();
 972                                 Process::deleteInactive();
 973
 974                                 return;
 975                         }
 976
 977                         self::runCron();
 978
 979                         Logger::log('Call worker', LOGGER_DEBUG);
 980                         self::spawnWorker();
 981                         return;
 982                 }
 983
 984                 // We cannot execute background processes.
 985                 // We now run the processes from the frontend.
 986                 // This won't work with long running processes.
 987                 self::runCron();
 988
 989                 self::clearProcesses();
 990
 991                 $workers = self::activeWorkers();
 992
 993                 if ($workers == 0) {
 994                         self::callWorker();
 995                 }
 996         }
 997
 998         /**
 999          * @brief Removes long running worker processes
1000          * @return void
1001          */
1002         public static function clearProcesses()
1003         {
1004                 $timeout = Config::get("system", "frontend_worker_timeout", 10);
1005
1006                 /// @todo We should clean up the corresponding workerqueue entries as well
1007                 $condition = ["`created` < ? AND `command` = 'worker.php'",
1008                                 DateTimeFormat::utc("now - ".$timeout." minutes")];
1009                 DBA::delete('process', $condition);
1010         }
1011
1012         /**
1013          * @brief Runs the cron processes
1014          * @return void
1015          */
1016         private static function runCron()
1017         {
1018                 Logger::log('Add cron entries', LOGGER_DEBUG);
1019
1020                 // Check for spooled items
1021                 self::add(PRIORITY_HIGH, "SpoolPost");
1022
1023                 // Run the cron job that calls all other jobs
1024                 self::add(PRIORITY_MEDIUM, "Cron");
1025
1026                 // Cleaning dead processes
1027                 self::killStaleWorkers();
1028         }
1029
1030         /**
1031          * @brief Spawns a new worker
1032          * @return void
1033          */
1034         public static function spawnWorker($do_cron = false)
1035         {
1036                 $command = 'bin/worker.php';
1037
1038                 $args = ['no_cron' => !$do_cron];
1039
1040                 get_app()->proc_run($command, $args);
1041
1042                 // after spawning we have to remove the flag.
1043                 if (Config::get('system', 'worker_daemon_mode', false)) {
1044                         self::IPCSetJobState(false);
1045                 }
1046         }
1047
1048         /**
1049          * @brief Adds tasks to the worker queue
1050          *
1051          * @param (integer|array) priority or parameter array, strings are deprecated and are ignored
1052          *
1053          * next args are passed as $cmd command line
1054          * or: Worker::add(PRIORITY_HIGH, "Notifier", "drop", $drop_id);
1055          * or: Worker::add(array('priority' => PRIORITY_HIGH, 'dont_fork' => true), "CreateShadowEntry", $post_id);
1056          *
1057          * @note $cmd and string args are surrounded with ""
1058          *
1059          * @hooks 'proc_run'
1060          *      array $arr
1061          *
1062          * @return boolean "false" if proc_run couldn't be executed
1063          */
1064         public static function add($cmd)
1065         {
1066                 $args = func_get_args();
1067
1068                 if (!count($args)) {
1069                         return false;
1070                 }
1071
1072                 $arr = ['args' => $args, 'run_cmd' => true];
1073
1074                 Addon::callHooks("proc_run", $arr);
1075                 if (!$arr['run_cmd'] || !count($args)) {
1076                         return true;
1077                 }
1078
1079                 $priority = PRIORITY_MEDIUM;
1080                 $dont_fork = Config::get("system", "worker_dont_fork", false);
1081                 $created = DateTimeFormat::utcNow();
1082
1083                 $run_parameter = array_shift($args);
1084
1085                 if (is_int($run_parameter)) {
1086                         $priority = $run_parameter;
1087                 } elseif (is_array($run_parameter)) {
1088                         if (isset($run_parameter['priority'])) {
1089                                 $priority = $run_parameter['priority'];
1090                         }
1091                         if (isset($run_parameter['created'])) {
1092                                 $created = $run_parameter['created'];
1093                         }
1094                         if (isset($run_parameter['dont_fork'])) {
1095                                 $dont_fork = $run_parameter['dont_fork'];
1096                         }
1097                 }
1098
1099                 $parameters = json_encode($args);
1100                 $found = DBA::exists('workerqueue', ['parameter' => $parameters, 'done' => false]);
1101
1102                 // Quit if there was a database error - a precaution for the update process to 3.5.3
1103                 if (DBA::errorNo() != 0) {
1104                         return false;
1105                 }
1106
1107                 if (!$found) {
1108                         DBA::insert('workerqueue', ['parameter' => $parameters, 'created' => $created, 'priority' => $priority]);
1109                 }
1110
1111                 // Should we quit and wait for the worker to be called as a cronjob?
1112                 if ($dont_fork) {
1113                         return true;
1114                 }
1115
1116                 // If there is a lock then we don't have to check for too much worker
1117                 if (!Lock::acquire('worker', 0)) {
1118                         return true;
1119                 }
1120
1121                 // If there are already enough workers running, don't fork another one
1122                 $quit = self::tooMuchWorkers();
1123                 Lock::release('worker');
1124
1125                 if ($quit) {
1126                         return true;
1127                 }
1128
1129                 // We tell the daemon that a new job entry exists
1130                 if (Config::get('system', 'worker_daemon_mode', false)) {
1131                         // We don't have to set the IPC flag - this is done in "tooMuchWorkers"
1132                         return true;
1133                 }
1134
1135                 // Now call the worker to execute the jobs that we just added to the queue
1136                 self::spawnWorker();
1137
1138                 return true;
1139         }
1140
1141         /**
1142          * Defers the current worker entry
1143          */
1144         public static function defer()
1145         {
1146                 if (empty(BaseObject::getApp()->queue)) {
1147                         return;
1148                 }
1149
1150                 $queue = BaseObject::getApp()->queue;
1151
1152                 $retrial = $queue['retrial'];
1153                 $id = $queue['id'];
1154
1155                 if ($retrial > 14) {
1156                         Logger::log('Id ' . $id . ' had been tried 14 times. We stop now.', LOGGER_DEBUG);
1157                         return;
1158                 }
1159
1160                 // Calculate the delay until the next trial
1161                 $delay = (($retrial + 3) ** 4) + (rand(1, 30) * ($retrial + 1));
1162                 $next = DateTimeFormat::utc('now + ' . $delay . ' seconds');
1163
1164                 Logger::log('Defer execution ' . $retrial . ' of id ' . $id . ' to ' . $next, LOGGER_DEBUG);
1165
1166                 $fields = ['retrial' => $retrial + 1, 'next_try' => $next, 'executed' => DBA::NULL_DATETIME, 'pid' => 0];
1167                 DBA::update('workerqueue', $fields, ['id' => $id]);
1168         }
1169
1170         /**
1171          * Log active processes into the "process" table
1172          *
1173          * @brief Log active processes into the "process" table
1174          */
1175         public static function startProcess()
1176         {
1177                 $trace = debug_backtrace(DEBUG_BACKTRACE_IGNORE_ARGS, 1);
1178
1179                 $command = basename($trace[0]['file']);
1180
1181                 Process::deleteInactive();
1182
1183                 Process::insert($command);
1184         }
1185
1186         /**
1187          * Remove the active process from the "process" table
1188          *
1189          * @brief Remove the active process from the "process" table
1190          * @return bool
1191          */
1192         public static function endProcess()
1193         {
1194                 return Process::deleteByPid();
1195         }
1196
1197         /**
1198          * Set the flag if some job is waiting
1199          *
1200          * @brief Set the flag if some job is waiting
1201          * @param boolean $jobs Is there a waiting job?
1202          */
1203         public static function IPCSetJobState($jobs)
1204         {
1205                 DBA::update('worker-ipc', ['jobs' => $jobs], ['key' => 1], true);
1206         }
1207
1208         /**
1209          * Checks if some worker job waits to be executed
1210          *
1211          * @brief Checks if some worker job waits to be executed
1212          * @return bool
1213          */
1214         public static function IPCJobsExists()
1215         {
1216                 $row = DBA::selectFirst('worker-ipc', ['jobs'], ['key' => 1]);
1217
1218                 // When we don't have a row, no job is running
1219                 if (!DBA::isResult($row)) {
1220                         return false;
1221                 }
1222
1223                 return (bool)$row['jobs'];
1224         }
1225 }