src/Core/Worker.php

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