src/Core/Worker.php

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