include/poller.php

   1 <?php
   2
   3 use Friendica\App;
   4 use Friendica\Core\Config;
   5 use Friendica\Util\Lock;
   6
   7 if (!file_exists("boot.php") AND (sizeof($_SERVER["argv"]) != 0)) {
   8         $directory = dirname($_SERVER["argv"][0]);
   9
  10         if (substr($directory, 0, 1) != "/")
  11                 $directory = $_SERVER["PWD"]."/".$directory;
  12
  13         $directory = realpath($directory."/..");
  14
  15         chdir($directory);
  16 }
  17
  18 require_once("boot.php");
  19
  20 function poller_run($argv, $argc){
  21         global $a, $db;
  22
  23         $a = new App(dirname(__DIR__));
  24
  25         @include(".htconfig.php");
  26         require_once("include/dba.php");
  27         $db = new dba($db_host, $db_user, $db_pass, $db_data);
  28         unset($db_host, $db_user, $db_pass, $db_data);
  29
  30         Config::load();
  31
  32         // Quit when in maintenance
  33         if (Config::get('system', 'maintenance', true)) {
  34                 return;
  35         }
  36
  37         $a->set_baseurl(Config::get('system', 'url'));
  38
  39         load_hooks();
  40
  41         if (($argc <= 1) OR ($argv[1] != "no_cron")) {
  42                 poller_run_cron();
  43         }
  44
  45         $a->start_process();
  46
  47         if ($a->min_memory_reached()) {
  48                 logger('Pre check: Memory limit reached, quitting.', LOGGER_DEBUG);
  49                 return;
  50         }
  51
  52         if (poller_max_connections_reached()) {
  53                 logger('Pre check: maximum connections reached, quitting.', LOGGER_DEBUG);
  54                 return;
  55         }
  56
  57         if ($a->maxload_reached()) {
  58                 logger('Pre check: maximum load reached, quitting.', LOGGER_DEBUG);
  59                 return;
  60         }
  61
  62         if ($a->max_processes_reached()) {
  63                 logger('Pre check: maximum processes reached, quitting.', LOGGER_DEBUG);
  64                 return;
  65         }
  66
  67         // Checking the number of workers
  68         if (poller_too_much_workers()) {
  69                 poller_kill_stale_workers();
  70                 logger('Pre check: Active worker limit reached, quitting.', LOGGER_DEBUG);
  71                 return;
  72         }
  73
  74         $starttime = time();
  75
  76         while ($r = poller_worker_process()) {
  77
  78                 if (!poller_claim_process($r[0])) {
  79                         continue;
  80                 }
  81
  82                 // Check free memory
  83                 if ($a->min_memory_reached()) {
  84                         logger('Memory limit reached, quitting.', LOGGER_DEBUG);
  85                         return;
  86                 }
  87
  88                 if (!Lock::set('poller_worker')) {
  89                         logger('Cannot get a lock, retrying.', LOGGER_DEBUG);
  90                         poller_unclaim_process();
  91                         continue;
  92                 }
  93
  94                 // Count active workers and compare them with a maximum value that depends on the load
  95                 if (poller_too_much_workers()) {
  96                         logger('Active worker limit reached, quitting.', LOGGER_DEBUG);
  97                         return;
  98                 }
  99
 100                 Lock::remove('poller_worker');
 101
 102                 if (!poller_execute($r[0])) {
 103                         logger('Process execution failed, quitting.', LOGGER_DEBUG);
 104                         return;
 105                 }
 106
 107                 // Quit the poller once every hour
 108                 if (time() > ($starttime + 360)) {
 109                         logger('Process lifetime reachted, quitting.', LOGGER_DEBUG);
 110                         return;
 111                 }
 112         }
 113         logger("Couldn't select a workerqueue entry, quitting.", LOGGER_DEBUG);
 114 }
 115
 116 /**
 117  * @brief Execute a worker entry
 118  *
 119  * @param array $queue Workerqueue entry
 120  *
 121  * @return boolean "true" if further processing should be stopped
 122  */
 123 function poller_execute($queue) {
 124
 125         $a = get_app();
 126
 127         $mypid = getmypid();
 128
 129         // Quit when in maintenance
 130         if (Config::get('system', 'maintenance', true)) {
 131                 logger("Maintenance mode - quit process ".$mypid, LOGGER_DEBUG);
 132                 return false;
 133         }
 134
 135         // Constantly check the number of parallel database processes
 136         if ($a->max_processes_reached()) {
 137                 logger("Max processes reached for process ".$mypid, LOGGER_DEBUG);
 138                 return false;
 139         }
 140
 141         // Constantly check the number of available database connections to let the frontend be accessible at any time
 142         if (poller_max_connections_reached()) {
 143                 logger("Max connection reached for process ".$mypid, LOGGER_DEBUG);
 144                 return false;
 145         }
 146
 147         $argv = json_decode($queue["parameter"]);
 148
 149         // Check for existance and validity of the include file
 150         $include = $argv[0];
 151
 152         if (!validate_include($include)) {
 153                 logger("Include file ".$argv[0]." is not valid!");
 154                 dba::delete('workerqueue', array('id' => $queue["id"]));
 155                 return true;
 156         }
 157
 158         require_once($include);
 159
 160         $funcname = str_replace(".php", "", basename($argv[0]))."_run";
 161
 162         if (function_exists($funcname)) {
 163
 164                 poller_exec_function($queue, $funcname, $argv);
 165                 dba::delete('workerqueue', array('id' => $queue["id"]));
 166         } else {
 167                 logger("Function ".$funcname." does not exist");
 168         }
 169
 170         return true;
 171 }
 172
 173 /**
 174  * @brief Execute a function from the queue
 175  *
 176  * @param array $queue Workerqueue entry
 177  * @param string $funcname name of the function
 178  * @param array $argv Array of values to be passed to the function
 179  */
 180 function poller_exec_function($queue, $funcname, $argv) {
 181
 182         $a = get_app();
 183
 184         $mypid = getmypid();
 185
 186         $argc = count($argv);
 187
 188         logger("Process ".$mypid." - Prio ".$queue["priority"]." - ID ".$queue["id"].": ".$funcname." ".$queue["parameter"]);
 189
 190         $stamp = (float)microtime(true);
 191
 192         // We use the callstack here to analyze the performance of executed worker entries.
 193         // For this reason the variables have to be initialized.
 194         if (Config::get("system", "profiler")) {
 195                 $a->performance["start"] = microtime(true);
 196                 $a->performance["database"] = 0;
 197                 $a->performance["database_write"] = 0;
 198                 $a->performance["network"] = 0;
 199                 $a->performance["file"] = 0;
 200                 $a->performance["rendering"] = 0;
 201                 $a->performance["parser"] = 0;
 202                 $a->performance["marktime"] = 0;
 203                 $a->performance["markstart"] = microtime(true);
 204                 $a->callstack = array();
 205         }
 206
 207         // For better logging create a new process id for every worker call
 208         // But preserve the old one for the worker
 209         $old_process_id = $a->process_id;
 210         $a->process_id = uniqid("wrk", true);
 211
 212         $funcname($argv, $argc);
 213
 214         $a->process_id = $old_process_id;
 215
 216         $duration = number_format(microtime(true) - $stamp, 3);
 217
 218         if ($duration > 3600) {
 219                 logger("Prio ".$queue["priority"].": ".$queue["parameter"]." - longer than 1 hour (".round($duration/60, 3).")", LOGGER_DEBUG);
 220         } elseif ($duration > 600) {
 221                 logger("Prio ".$queue["priority"].": ".$queue["parameter"]." - longer than 10 minutes (".round($duration/60, 3).")", LOGGER_DEBUG);
 222         } elseif ($duration > 300) {
 223                 logger("Prio ".$queue["priority"].": ".$queue["parameter"]." - longer than 5 minutes (".round($duration/60, 3).")", LOGGER_DEBUG);
 224         } elseif ($duration > 120) {
 225                 logger("Prio ".$queue["priority"].": ".$queue["parameter"]." - longer than 2 minutes (".round($duration/60, 3).")", LOGGER_DEBUG);
 226         }
 227
 228         logger("Process ".$mypid." - Prio ".$queue["priority"]." - ID ".$queue["id"].": ".$funcname." - done in ".$duration." seconds.");
 229
 230         // Write down the performance values into the log
 231         if (Config::get("system", "profiler")) {
 232                 $duration = microtime(true)-$a->performance["start"];
 233
 234                 if (Config::get("rendertime", "callstack")) {
 235                         if (isset($a->callstack["database"])) {
 236                                 $o = "\nDatabase Read:\n";
 237                                 foreach ($a->callstack["database"] AS $func => $time) {
 238                                         $time = round($time, 3);
 239                                         if ($time > 0)
 240                                                 $o .= $func.": ".$time."\n";
 241                                 }
 242                         }
 243                         if (isset($a->callstack["database_write"])) {
 244                                 $o .= "\nDatabase Write:\n";
 245                                 foreach ($a->callstack["database_write"] AS $func => $time) {
 246                                         $time = round($time, 3);
 247                                         if ($time > 0)
 248                                                 $o .= $func.": ".$time."\n";
 249                                 }
 250                         }
 251                         if (isset($a->callstack["network"])) {
 252                                 $o .= "\nNetwork:\n";
 253                                 foreach ($a->callstack["network"] AS $func => $time) {
 254                                         $time = round($time, 3);
 255                                         if ($time > 0)
 256                                                 $o .= $func.": ".$time."\n";
 257                                 }
 258                         }
 259                 } else {
 260                         $o = '';
 261                 }
 262
 263                 logger("ID ".$queue["id"].": ".$funcname.": ".sprintf("DB: %s/%s, Net: %s, I/O: %s, Other: %s, Total: %s".$o,
 264                         number_format($a->performance["database"] - $a->performance["database_write"], 2),
 265                         number_format($a->performance["database_write"], 2),
 266                         number_format($a->performance["network"], 2),
 267                         number_format($a->performance["file"], 2),
 268                         number_format($duration - ($a->performance["database"] + $a->performance["network"] + $a->performance["file"]), 2),
 269                         number_format($duration, 2)),
 270                         LOGGER_DEBUG);
 271         }
 272
 273         $cooldown = Config::get("system", "worker_cooldown", 0);
 274
 275         if ($cooldown > 0) {
 276                 logger("Process ".$mypid." - Prio ".$queue["priority"]." - ID ".$queue["id"].": ".$funcname." - in cooldown for ".$cooldown." seconds");
 277                 sleep($cooldown);
 278         }
 279 }
 280
 281 /**
 282  * @brief Checks if the number of database connections has reached a critical limit.
 283  *
 284  * @return bool Are more than 3/4 of the maximum connections used?
 285  */
 286 function poller_max_connections_reached() {
 287
 288         // Fetch the max value from the config. This is needed when the system cannot detect the correct value by itself.
 289         $max = Config::get("system", "max_connections");
 290
 291         // Fetch the percentage level where the poller will get active
 292         $maxlevel = Config::get("system", "max_connections_level", 75);
 293
 294         if ($max == 0) {
 295                 // the maximum number of possible user connections can be a system variable
 296                 $r = q("SHOW VARIABLES WHERE `variable_name` = 'max_user_connections'");
 297                 if ($r)
 298                         $max = $r[0]["Value"];
 299
 300                 // Or it can be granted. This overrides the system variable
 301                 $r = q("SHOW GRANTS");
 302                 if ($r)
 303                         foreach ($r AS $grants) {
 304                                 $grant = array_pop($grants);
 305                                 if (stristr($grant, "GRANT USAGE ON"))
 306                                         if (preg_match("/WITH MAX_USER_CONNECTIONS (\d*)/", $grant, $match))
 307                                                 $max = $match[1];
 308                         }
 309         }
 310
 311         // If $max is set we will use the processlist to determine the current number of connections
 312         // The processlist only shows entries of the current user
 313         if ($max != 0) {
 314                 $r = q("SHOW PROCESSLIST");
 315                 if (!dbm::is_result($r))
 316                         return false;
 317
 318                 $used = count($r);
 319
 320                 logger("Connection usage (user values): ".$used."/".$max, LOGGER_DEBUG);
 321
 322                 $level = ($used / $max) * 100;
 323
 324                 if ($level >= $maxlevel) {
 325                         logger("Maximum level (".$maxlevel."%) of user connections reached: ".$used."/".$max);
 326                         return true;
 327                 }
 328         }
 329
 330         // We will now check for the system values.
 331         // This limit could be reached although the user limits are fine.
 332         $r = q("SHOW VARIABLES WHERE `variable_name` = 'max_connections'");
 333         if (!$r)
 334                 return false;
 335
 336         $max = intval($r[0]["Value"]);
 337         if ($max == 0)
 338                 return false;
 339
 340         $r = q("SHOW STATUS WHERE `variable_name` = 'Threads_connected'");
 341         if (!$r)
 342                 return false;
 343
 344         $used = intval($r[0]["Value"]);
 345         if ($used == 0)
 346                 return false;
 347
 348         logger("Connection usage (system values): ".$used."/".$max, LOGGER_DEBUG);
 349
 350         $level = $used / $max * 100;
 351
 352         if ($level < $maxlevel)
 353                 return false;
 354
 355         logger("Maximum level (".$level."%) of system connections reached: ".$used."/".$max);
 356         return true;
 357 }
 358
 359 /**
 360  * @brief fix the queue entry if the worker process died
 361  *
 362  */
 363 function poller_kill_stale_workers() {
 364         $r = q("SELECT `pid`, `executed`, `priority`, `parameter` FROM `workerqueue` WHERE `executed` > '%s'", dbesc(NULL_DATE));
 365
 366         if (!dbm::is_result($r)) {
 367                 // No processing here needed
 368                 return;
 369         }
 370
 371         foreach ($r AS $pid) {
 372                 if (!posix_kill($pid["pid"], 0)) {
 373                         dba::update('workerqueue', array('executed' => NULL_DATE, 'pid' => 0),
 374                                         array('pid' => $pid["pid"]));
 375                 } else {
 376                         // Kill long running processes
 377
 378                         // Check if the priority is in a valid range
 379                         if (!in_array($pid["priority"], array(PRIORITY_CRITICAL, PRIORITY_HIGH, PRIORITY_MEDIUM, PRIORITY_LOW, PRIORITY_NEGLIGIBLE)))
 380                                 $pid["priority"] = PRIORITY_MEDIUM;
 381
 382                         // Define the maximum durations
 383                         $max_duration_defaults = array(PRIORITY_CRITICAL => 360, PRIORITY_HIGH => 10, PRIORITY_MEDIUM => 60, PRIORITY_LOW => 180, PRIORITY_NEGLIGIBLE => 360);
 384                         $max_duration = $max_duration_defaults[$pid["priority"]];
 385
 386                         $argv = json_decode($pid["parameter"]);
 387                         $argv[0] = basename($argv[0]);
 388
 389                         // How long is the process already running?
 390                         $duration = (time() - strtotime($pid["executed"])) / 60;
 391                         if ($duration > $max_duration) {
 392                                 logger("Worker process ".$pid["pid"]." (".implode(" ", $argv).") took more than ".$max_duration." minutes. It will be killed now.");
 393                                 posix_kill($pid["pid"], SIGTERM);
 394
 395                                 // We killed the stale process.
 396                                 // To avoid a blocking situation we reschedule the process at the beginning of the queue.
 397                                 // Additionally we are lowering the priority.
 398                                 dba::update('workerqueue',
 399                                                 array('executed' => NULL_DATE, 'created' => datetime_convert(), 'priority' => PRIORITY_NEGLIGIBLE, 'pid' => 0),
 400                                                 array('pid' => $pid["pid"]));
 401                         } else {
 402                                 logger("Worker process ".$pid["pid"]." (".implode(" ", $argv).") now runs for ".round($duration)." of ".$max_duration." allowed minutes. That's okay.", LOGGER_DEBUG);
 403                         }
 404                 }
 405         }
 406 }
 407
 408 /**
 409  * @brief Checks if the number of active workers exceeds the given limits
 410  *
 411  * @return bool Are there too much workers running?
 412  */
 413 function poller_too_much_workers() {
 414         $queues = Config::get("system", "worker_queues", 4);
 415
 416         $maxqueues = $queues;
 417
 418         $active = poller_active_workers();
 419
 420         // Decrease the number of workers at higher load
 421         $load = current_load();
 422         if ($load) {
 423                 $maxsysload = intval(Config::get("system", "maxloadavg", 50));
 424
 425                 $maxworkers = $queues;
 426
 427                 // Some magical mathemathics to reduce the workers
 428                 $exponent = 3;
 429                 $slope = $maxworkers / pow($maxsysload, $exponent);
 430                 $queues = ceil($slope * pow(max(0, $maxsysload - $load), $exponent));
 431
 432                 // Create a list of queue entries grouped by their priority
 433                 $listitem = array();
 434
 435                 // Adding all processes with no workerqueue entry
 436                 $processes = dba::p("SELECT COUNT(*) AS `running` FROM `process` WHERE NOT EXISTS (SELECT id FROM `workerqueue` WHERE `workerqueue`.`pid` = `process`.`pid`)");
 437                 if ($process = dba::fetch($processes)) {
 438                         $listitem[0] = "0:".$process["running"];
 439                 }
 440                 dba::close($processes);
 441
 442                 // Now adding all processes with workerqueue entries
 443                 $entries = dba::p("SELECT COUNT(*) AS `entries`, `priority` FROM `workerqueue` GROUP BY `priority`");
 444                 while ($entry = dba::fetch($entries)) {
 445                         $processes = dba::p("SELECT COUNT(*) AS `running` FROM `process` INNER JOIN `workerqueue` ON `workerqueue`.`pid` = `process`.`pid` WHERE `priority` = ?", $entry["priority"]);
 446                         if ($process = dba::fetch($processes)) {
 447                                 $listitem[$entry["priority"]] = $entry["priority"].":".$process["running"]."/".$entry["entries"];
 448                         }
 449                         dba::close($processes);
 450                 }
 451                 dba::close($entries);
 452
 453                 $processlist = implode(', ', $listitem);
 454
 455                 $s = q("SELECT COUNT(*) AS `total` FROM `workerqueue` WHERE `executed` <= '%s'", dbesc(NULL_DATE));
 456                 $entries = $s[0]["total"];
 457
 458                 if (Config::get("system", "worker_fastlane", false) AND ($queues > 0) AND ($entries > 0) AND ($active >= $queues)) {
 459                         $s = q("SELECT `priority` FROM `workerqueue` WHERE `executed` <= '%s' ORDER BY `priority` LIMIT 1", dbesc(NULL_DATE));
 460                         $top_priority = $s[0]["priority"];
 461
 462                         $s = q("SELECT `id` FROM `workerqueue` WHERE `priority` <= %d AND `executed` > '%s' LIMIT 1",
 463                                 intval($top_priority), dbesc(NULL_DATE));
 464                         $high_running = dbm::is_result($s);
 465
 466                         if (!$high_running AND ($top_priority > PRIORITY_UNDEFINED) AND ($top_priority < PRIORITY_NEGLIGIBLE)) {
 467                                 logger("There are jobs with priority ".$top_priority." waiting but none is executed. Open a fastlane.", LOGGER_DEBUG);
 468                                 $queues = $active + 1;
 469                         }
 470                 }
 471
 472                 logger("Load: ".$load."/".$maxsysload." - processes: ".$active."/".$entries." (".$processlist.") - maximum: ".$queues."/".$maxqueues, LOGGER_DEBUG);
 473
 474                 // Are there fewer workers running as possible? Then fork a new one.
 475                 if (!Config::get("system", "worker_dont_fork") AND ($queues > ($active + 1)) AND ($entries > 1)) {
 476                         logger("Active workers: ".$active."/".$queues." Fork a new worker.", LOGGER_DEBUG);
 477                         $args = array("include/poller.php", "no_cron");
 478                         $a = get_app();
 479                         $a->proc_run($args);
 480                 }
 481         }
 482
 483         return($active >= $queues);
 484 }
 485
 486 /**
 487  * @brief Returns the number of active poller processes
 488  *
 489  * @return integer Number of active poller processes
 490  */
 491 function poller_active_workers() {
 492         $workers = q("SELECT COUNT(*) AS `processes` FROM `process` WHERE `command` = 'poller.php'");
 493
 494         return($workers[0]["processes"]);
 495 }
 496
 497 /**
 498  * @brief Check if we should pass some slow processes
 499  *
 500  * When the active processes of the highest priority are using more than 2/3
 501  * of all processes, we let pass slower processes.
 502  *
 503  * @param string $highest_priority Returns the currently highest priority
 504  * @return bool We let pass a slower process than $highest_priority
 505  */
 506 function poller_passing_slow(&$highest_priority) {
 507
 508         $highest_priority = 0;
 509
 510         $r = q("SELECT `priority`
 511                 FROM `process`
 512                 INNER JOIN `workerqueue` ON `workerqueue`.`pid` = `process`.`pid`");
 513
 514         // No active processes at all? Fine
 515         if (!dbm::is_result($r))
 516                 return(false);
 517
 518         $priorities = array();
 519         foreach ($r AS $line)
 520                 $priorities[] = $line["priority"];
 521
 522         // Should not happen
 523         if (count($priorities) == 0)
 524                 return(false);
 525
 526         $highest_priority = min($priorities);
 527
 528         // The highest process is already the slowest one?
 529         // Then we quit
 530         if ($highest_priority == PRIORITY_NEGLIGIBLE)
 531                 return(false);
 532
 533         $high = 0;
 534         foreach ($priorities AS $priority)
 535                 if ($priority == $highest_priority)
 536                         ++$high;
 537
 538         logger("Highest priority: ".$highest_priority." Total processes: ".count($priorities)." Count high priority processes: ".$high, LOGGER_DEBUG);
 539         $passing_slow = (($high/count($priorities)) > (2/3));
 540
 541         if ($passing_slow)
 542                 logger("Passing slower processes than priority ".$highest_priority, LOGGER_DEBUG);
 543
 544         return($passing_slow);
 545 }
 546
 547 /**
 548  * @brief Returns the next worker process
 549  *
 550  * @return string SQL statement
 551  */
 552 function poller_worker_process() {
 553
 554         // Check if we should pass some low priority process
 555         $highest_priority = 0;
 556
 557         if (poller_passing_slow($highest_priority)) {
 558                 dba::p('LOCK TABLES `workerqueue` WRITE');
 559
 560                 // Are there waiting processes with a higher priority than the currently highest?
 561                 $r = q("SELECT * FROM `workerqueue`
 562                                 WHERE `executed` <= '%s' AND `priority` < %d
 563                                 ORDER BY `priority`, `created` LIMIT 1",
 564                                 dbesc(NULL_DATE),
 565                                 intval($highest_priority));
 566                 if (dbm::is_result($r)) {
 567                         return $r;
 568                 }
 569                 // Give slower processes some processing time
 570                 $r = q("SELECT * FROM `workerqueue`
 571                                 WHERE `executed` <= '%s' AND `priority` > %d
 572                                 ORDER BY `priority`, `created` LIMIT 1",
 573                                 dbesc(NULL_DATE),
 574                                 intval($highest_priority));
 575
 576                 if (dbm::is_result($r)) {
 577                         return $r;
 578                 }
 579         } else {
 580                 dba::p('LOCK TABLES `workerqueue` WRITE');
 581         }
 582
 583         // If there is no result (or we shouldn't pass lower processes) we check without priority limit
 584         if (!dbm::is_result($r)) {
 585                 $r = q("SELECT * FROM `workerqueue` WHERE `executed` <= '%s' ORDER BY `priority`, `created` LIMIT 1", dbesc(NULL_DATE));
 586         }
 587
 588         // We only unlock the tables here, when we got no data
 589         if (!dbm::is_result($r)) {
 590                 dba::p('UNLOCK TABLES');
 591         }
 592
 593         return $r;
 594 }
 595
 596 /**
 597  * @brief Assigns a workerqueue entry to the current process
 598  *
 599  * When we are sure that the table locks are working correctly, we can remove the checks from here
 600  *
 601  * @param array $queue Workerqueue entry
 602  *
 603  * @return boolean "true" if the claiming was successful
 604  */
 605 function poller_claim_process($queue) {
 606         $mypid = getmypid();
 607
 608         $success = dba::update('workerqueue', array('executed' => datetime_convert(), 'pid' => $mypid),
 609                         array('id' => $queue["id"], 'pid' => 0));
 610         dba::p('UNLOCK TABLES');
 611
 612         if (!$success) {
 613                 logger("Couldn't update queue entry ".$queue["id"]." - skip this execution", LOGGER_DEBUG);
 614                 return false;
 615         }
 616
 617         // Assure that there are no tasks executed twice
 618         $id = q("SELECT `pid`, `executed` FROM `workerqueue` WHERE `id` = %d", intval($queue["id"]));
 619         if (!$id) {
 620                 logger("Queue item ".$queue["id"]." vanished - skip this execution", LOGGER_DEBUG);
 621                 return false;
 622         } elseif ((strtotime($id[0]["executed"]) <= 0) OR ($id[0]["pid"] == 0)) {
 623                 logger("Entry for queue item ".$queue["id"]." wasn't stored - skip this execution", LOGGER_DEBUG);
 624                 return false;
 625         } elseif ($id[0]["pid"] != $mypid) {
 626                 logger("Queue item ".$queue["id"]." is to be executed by process ".$id[0]["pid"]." and not by me (".$mypid.") - skip this execution", LOGGER_DEBUG);
 627                 return false;
 628         }
 629         return true;
 630 }
 631
 632 /**
 633  * @brief Removes a workerqueue entry from the current process
 634  */
 635 function poller_unclaim_process() {
 636         $mypid = getmypid();
 637
 638         dba::update('workerqueue', array('executed' => NULL_DATE, 'pid' => 0), array('pid' => $mypid));
 639 }
 640
 641 /**
 642  * @brief Call the front end worker
 643  */
 644 function call_worker() {
 645         if (!Config::get("system", "frontend_worker")) {
 646                 return;
 647         }
 648
 649         $url = App::get_baseurl()."/worker";
 650         fetch_url($url, false, $redirects, 1);
 651 }
 652
 653 /**
 654  * @brief Call the front end worker if there aren't any active
 655  */
 656 function call_worker_if_idle() {
 657         if (!Config::get("system", "frontend_worker")) {
 658                 return;
 659         }
 660
 661         // Do we have "proc_open"? Then we can fork the poller
 662         if (function_exists("proc_open")) {
 663                 // When was the last time that we called the worker?
 664                 // Less than one minute? Then we quit
 665                 if ((time() - Config::get("system", "worker_started")) < 60) {
 666                         return;
 667                 }
 668
 669                 set_config("system", "worker_started", time());
 670
 671                 // Do we have enough running workers? Then we quit here.
 672                 if (poller_too_much_workers()) {
 673                         // Cleaning dead processes
 674                         poller_kill_stale_workers();
 675                         get_app()->remove_inactive_processes();
 676
 677                         return;
 678                 }
 679
 680                 poller_run_cron();
 681
 682                 logger('Call poller', LOGGER_DEBUG);
 683
 684                 $args = array("include/poller.php", "no_cron");
 685                 $a = get_app();
 686                 $a->proc_run($args);
 687                 return;
 688         }
 689
 690         // We cannot execute background processes.
 691         // We now run the processes from the frontend.
 692         // This won't work with long running processes.
 693         poller_run_cron();
 694
 695         clear_worker_processes();
 696
 697         $workers = q("SELECT COUNT(*) AS `processes` FROM `process` WHERE `command` = 'worker.php'");
 698
 699         if ($workers[0]["processes"] == 0) {
 700                 call_worker();
 701         }
 702 }
 703
 704 /**
 705  * @brief Removes long running worker processes
 706  */
 707 function clear_worker_processes() {
 708         $timeout = Config::get("system", "frontend_worker_timeout", 10);
 709
 710         /// @todo We should clean up the corresponding workerqueue entries as well
 711         q("DELETE FROM `process` WHERE `created` < '%s' AND `command` = 'worker.php'",
 712                 dbesc(datetime_convert('UTC','UTC',"now - ".$timeout." minutes")));
 713 }
 714
 715 /**
 716  * @brief Runs the cron processes
 717  */
 718 function poller_run_cron() {
 719         logger('Add cron entries', LOGGER_DEBUG);
 720
 721         // Check for spooled items
 722         proc_run(PRIORITY_HIGH, "include/spool_post.php");
 723
 724         // Run the cron job that calls all other jobs
 725         proc_run(PRIORITY_MEDIUM, "include/cron.php");
 726
 727         // Run the cronhooks job separately from cron for being able to use a different timing
 728         proc_run(PRIORITY_MEDIUM, "include/cronhooks.php");
 729
 730         // Cleaning dead processes
 731         poller_kill_stale_workers();
 732 }
 733
 734 if (array_search(__file__,get_included_files())===0){
 735         poller_run($_SERVER["argv"],$_SERVER["argc"]);
 736
 737         Lock::remove('poller_worker');
 738
 739         poller_unclaim_process();
 740
 741         get_app()->end_process();
 742
 743         killme();
 744 }