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") && (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, $poller_up_start;
  22
  23         $poller_up_start = microtime(true);
  24
  25         $a = new App(dirname(__DIR__));
  26
  27         @include(".htconfig.php");
  28         require_once("include/dba.php");
  29         $db = new dba($db_host, $db_user, $db_pass, $db_data);
  30         unset($db_host, $db_user, $db_pass, $db_data);
  31
  32         Config::load();
  33
  34         // Quit when in maintenance
  35         if (Config::get('system', 'maintenance', true)) {
  36                 return;
  37         }
  38
  39         $a->set_baseurl(Config::get('system', 'url'));
  40
  41         load_hooks();
  42
  43         // At first check the maximum load. We shouldn't continue with a high load
  44         if ($a->maxload_reached()) {
  45                 logger('Pre check: maximum load reached, quitting.', LOGGER_DEBUG);
  46                 return;
  47         }
  48
  49         // We now start the process. This is done after the load check since this could increase the load.
  50         $a->start_process();
  51
  52         // Kill stale processes every 5 minutes
  53         $last_cleanup = Config::get('system', 'poller_last_cleaned', 0);
  54         if (time() > ($last_cleanup + 300)) {
  55                 Config::set('system', 'poller_last_cleaned', time());
  56                 poller_kill_stale_workers();
  57         }
  58
  59         // Count active workers and compare them with a maximum value that depends on the load
  60         if (poller_too_much_workers()) {
  61                 logger('Pre check: Active worker limit reached, quitting.', LOGGER_DEBUG);
  62                 return;
  63         }
  64
  65         // Do we have too few memory?
  66         if ($a->min_memory_reached()) {
  67                 logger('Pre check: Memory limit reached, quitting.', LOGGER_DEBUG);
  68                 return;
  69         }
  70
  71         // Possibly there are too much database connections
  72         if (poller_max_connections_reached()) {
  73                 logger('Pre check: maximum connections reached, quitting.', LOGGER_DEBUG);
  74                 return;
  75         }
  76
  77         // Possibly there are too much database processes that block the system
  78         if ($a->max_processes_reached()) {
  79                 logger('Pre check: maximum processes reached, quitting.', LOGGER_DEBUG);
  80                 return;
  81         }
  82
  83         // Now we start additional cron processes if we should do so
  84         if (($argc <= 1) || ($argv[1] != "no_cron")) {
  85                 poller_run_cron();
  86         }
  87
  88         $refetched = false;
  89
  90         $starttime = time();
  91
  92         // We fetch the next queue entry that is about to be executed
  93         while ($r = poller_worker_process()) {
  94                 foreach ($r AS $entry) {
  95                         // Assure that the priority is an integer value
  96                         $entry['priority'] = (int)$entry['priority'];
  97
  98                         // The work will be done
  99                         if (!poller_execute($entry)) {
 100                                 logger('Process execution failed, quitting.', LOGGER_DEBUG);
 101                                 return;
 102                         }
 103                 }
 104
 105                 // To avoid the quitting of multiple pollers only one poller at a time will execute the check
 106                 if (Lock::set('poller_worker', 0)) {
 107                         // Count active workers and compare them with a maximum value that depends on the load
 108                         if (poller_too_much_workers()) {
 109                                 logger('Active worker limit reached, quitting.', LOGGER_DEBUG);
 110                                 return;
 111                         }
 112
 113                         // Check free memory
 114                         if ($a->min_memory_reached()) {
 115                                 logger('Memory limit reached, quitting.', LOGGER_DEBUG);
 116                                 return;
 117                         }
 118                         Lock::remove('poller_worker');
 119                 }
 120
 121                 // Quit the poller once every 5 minutes
 122                 if (time() > ($starttime + 300)) {
 123                         logger('Process lifetime reached, quitting.', LOGGER_DEBUG);
 124                         return;
 125                 }
 126
 127                 // If possible we will fetch new jobs for this worker
 128                 if (!$refetched && Lock::set('poller_worker_process', 0)) {
 129                         $refetched = find_worker_processes();
 130                         Lock::remove('poller_worker_process');
 131                 }
 132
 133         }
 134         logger("Couldn't select a workerqueue entry, quitting.", LOGGER_DEBUG);
 135 }
 136
 137 /**
 138  * @brief Returns the number of non executed entries in the worker queue
 139  *
 140  * @return integer Number of non executed entries in the worker queue
 141  */
 142 function poller_total_entries() {
 143         $s = q("SELECT COUNT(*) AS `total` FROM `workerqueue` WHERE `executed` <= '%s' AND NOT `done`", dbesc(NULL_DATE));
 144         if (dbm::is_result($s)) {
 145                 return $s[0]["total"];
 146         } else {
 147                 return 0;
 148         }
 149 }
 150
 151 /**
 152  * @brief Returns the highest priority in the worker queue that isn't executed
 153  *
 154  * @return integer Number of active poller processes
 155  */
 156 function poller_highest_priority() {
 157         $s = q("SELECT `priority` FROM `workerqueue` WHERE `executed` <= '%s' AND NOT `done` ORDER BY `priority` LIMIT 1", dbesc(NULL_DATE));
 158         if (dbm::is_result($s)) {
 159                 return $s[0]["priority"];
 160         } else {
 161                 return 0;
 162         }
 163 }
 164
 165 /**
 166  * @brief Returns if a process with the given priority is running
 167  *
 168  * @param integer $priority The priority that should be checked
 169  *
 170  * @return integer Is there a process running with that priority?
 171  */
 172 function poller_process_with_priority_active($priority) {
 173         $s = q("SELECT `id` FROM `workerqueue` WHERE `priority` <= %d AND `executed` > '%s' AND NOT `done` LIMIT 1",
 174                         intval($priority), dbesc(NULL_DATE));
 175         return dbm::is_result($s);
 176 }
 177
 178 /**
 179  * @brief Execute a worker entry
 180  *
 181  * @param array $queue Workerqueue entry
 182  *
 183  * @return boolean "true" if further processing should be stopped
 184  */
 185 function poller_execute($queue) {
 186         global $poller_db_duration;
 187
 188         $a = get_app();
 189
 190         $mypid = getmypid();
 191
 192         // Quit when in maintenance
 193         if (Config::get('system', 'maintenance', true)) {
 194                 logger("Maintenance mode - quit process ".$mypid, LOGGER_DEBUG);
 195                 return false;
 196         }
 197
 198         // Constantly check the number of parallel database processes
 199         if ($a->max_processes_reached()) {
 200                 logger("Max processes reached for process ".$mypid, LOGGER_DEBUG);
 201                 return false;
 202         }
 203
 204         // Constantly check the number of available database connections to let the frontend be accessible at any time
 205         if (poller_max_connections_reached()) {
 206                 logger("Max connection reached for process ".$mypid, LOGGER_DEBUG);
 207                 return false;
 208         }
 209
 210         $argv = json_decode($queue["parameter"]);
 211
 212         // Check for existance and validity of the include file
 213         $include = $argv[0];
 214
 215         if (!validate_include($include)) {
 216                 logger("Include file ".$argv[0]." is not valid!");
 217                 dba::delete('workerqueue', array('id' => $queue["id"]));
 218                 return true;
 219         }
 220
 221         require_once($include);
 222
 223         $funcname = str_replace(".php", "", basename($argv[0]))."_run";
 224
 225         if (function_exists($funcname)) {
 226                 poller_exec_function($queue, $funcname, $argv);
 227
 228                 $stamp = (float)microtime(true);
 229                 dba::update('workerqueue', array('done' => true), array('id' => $queue["id"]));
 230                 $poller_db_duration = (microtime(true) - $stamp);
 231         } else {
 232                 logger("Function ".$funcname." does not exist");
 233                 dba::delete('workerqueue', array('id' => $queue["id"]));
 234         }
 235
 236         return true;
 237 }
 238
 239 /**
 240  * @brief Execute a function from the queue
 241  *
 242  * @param array $queue Workerqueue entry
 243  * @param string $funcname name of the function
 244  * @param array $argv Array of values to be passed to the function
 245  */
 246 function poller_exec_function($queue, $funcname, $argv) {
 247         global $poller_up_start, $poller_db_duration, $poller_lock_duration;
 248
 249         $a = get_app();
 250
 251         $mypid = getmypid();
 252
 253         $argc = count($argv);
 254
 255         logger("Process ".$mypid." - Prio ".$queue["priority"]." - ID ".$queue["id"].": ".$funcname." ".$queue["parameter"]);
 256
 257         $stamp = (float)microtime(true);
 258
 259         // We use the callstack here to analyze the performance of executed worker entries.
 260         // For this reason the variables have to be initialized.
 261         if (Config::get("system", "profiler")) {
 262                 $a->performance["start"] = microtime(true);
 263                 $a->performance["database"] = 0;
 264                 $a->performance["database_write"] = 0;
 265                 $a->performance["network"] = 0;
 266                 $a->performance["file"] = 0;
 267                 $a->performance["rendering"] = 0;
 268                 $a->performance["parser"] = 0;
 269                 $a->performance["marktime"] = 0;
 270                 $a->performance["markstart"] = microtime(true);
 271                 $a->callstack = array();
 272         }
 273
 274         // For better logging create a new process id for every worker call
 275         // But preserve the old one for the worker
 276         $old_process_id = $a->process_id;
 277         $a->process_id = uniqid("wrk", true);
 278         $a->queue = $queue;
 279
 280         $up_duration = number_format(microtime(true) - $poller_up_start, 3);
 281
 282         $funcname($argv, $argc);
 283
 284         $a->process_id = $old_process_id;
 285         unset($a->queue);
 286
 287         $duration = number_format(microtime(true) - $stamp, 3);
 288
 289         $poller_up_start = microtime(true);
 290
 291         /* With these values we can analyze how effective the worker is.
 292          * The database and rest time should be low since this is the unproductive time.
 293          * The execution time is the productive time.
 294          * By changing parameters like the maximum number of workers we can check the effectivness.
 295         */
 296         logger('DB: '.number_format($poller_db_duration, 2).
 297                 ' - Lock: '.number_format($poller_lock_duration, 2).
 298                 ' - Rest: '.number_format($up_duration - $poller_db_duration - $poller_lock_duration, 2).
 299                 ' - Execution: '.number_format($duration, 2), LOGGER_DEBUG);
 300         $poller_lock_duration = 0;
 301
 302         if ($duration > 3600) {
 303                 logger("Prio ".$queue["priority"].": ".$queue["parameter"]." - longer than 1 hour (".round($duration/60, 3).")", LOGGER_DEBUG);
 304         } elseif ($duration > 600) {
 305                 logger("Prio ".$queue["priority"].": ".$queue["parameter"]." - longer than 10 minutes (".round($duration/60, 3).")", LOGGER_DEBUG);
 306         } elseif ($duration > 300) {
 307                 logger("Prio ".$queue["priority"].": ".$queue["parameter"]." - longer than 5 minutes (".round($duration/60, 3).")", LOGGER_DEBUG);
 308         } elseif ($duration > 120) {
 309                 logger("Prio ".$queue["priority"].": ".$queue["parameter"]." - longer than 2 minutes (".round($duration/60, 3).")", LOGGER_DEBUG);
 310         }
 311
 312         logger("Process ".$mypid." - Prio ".$queue["priority"]." - ID ".$queue["id"].": ".$funcname." - done in ".$duration." seconds.");
 313
 314         // Write down the performance values into the log
 315         if (Config::get("system", "profiler")) {
 316                 $duration = microtime(true)-$a->performance["start"];
 317
 318                 if (Config::get("rendertime", "callstack")) {
 319                         if (isset($a->callstack["database"])) {
 320                                 $o = "\nDatabase Read:\n";
 321                                 foreach ($a->callstack["database"] AS $func => $time) {
 322                                         $time = round($time, 3);
 323                                         if ($time > 0) {
 324                                                 $o .= $func.": ".$time."\n";
 325                                         }
 326                                 }
 327                         }
 328                         if (isset($a->callstack["database_write"])) {
 329                                 $o .= "\nDatabase Write:\n";
 330                                 foreach ($a->callstack["database_write"] AS $func => $time) {
 331                                         $time = round($time, 3);
 332                                         if ($time > 0) {
 333                                                 $o .= $func.": ".$time."\n";
 334                                         }
 335                                 }
 336                         }
 337                         if (isset($a->callstack["network"])) {
 338                                 $o .= "\nNetwork:\n";
 339                                 foreach ($a->callstack["network"] AS $func => $time) {
 340                                         $time = round($time, 3);
 341                                         if ($time > 0) {
 342                                                 $o .= $func.": ".$time."\n";
 343                                         }
 344                                 }
 345                         }
 346                 } else {
 347                         $o = '';
 348                 }
 349
 350                 logger("ID ".$queue["id"].": ".$funcname.": ".sprintf("DB: %s/%s, Net: %s, I/O: %s, Other: %s, Total: %s".$o,
 351                         number_format($a->performance["database"] - $a->performance["database_write"], 2),
 352                         number_format($a->performance["database_write"], 2),
 353                         number_format($a->performance["network"], 2),
 354                         number_format($a->performance["file"], 2),
 355                         number_format($duration - ($a->performance["database"] + $a->performance["network"] + $a->performance["file"]), 2),
 356                         number_format($duration, 2)),
 357                         LOGGER_DEBUG);
 358         }
 359
 360         $cooldown = Config::get("system", "worker_cooldown", 0);
 361
 362         if ($cooldown > 0) {
 363                 logger("Process ".$mypid." - Prio ".$queue["priority"]." - ID ".$queue["id"].": ".$funcname." - in cooldown for ".$cooldown." seconds");
 364                 sleep($cooldown);
 365         }
 366 }
 367
 368 /**
 369  * @brief Checks if the number of database connections has reached a critical limit.
 370  *
 371  * @return bool Are more than 3/4 of the maximum connections used?
 372  */
 373 function poller_max_connections_reached() {
 374
 375         // Fetch the max value from the config. This is needed when the system cannot detect the correct value by itself.
 376         $max = Config::get("system", "max_connections");
 377
 378         // Fetch the percentage level where the poller will get active
 379         $maxlevel = Config::get("system", "max_connections_level", 75);
 380
 381         if ($max == 0) {
 382                 // the maximum number of possible user connections can be a system variable
 383                 $r = q("SHOW VARIABLES WHERE `variable_name` = 'max_user_connections'");
 384                 if (dbm::is_result($r)) {
 385                         $max = $r[0]["Value"];
 386                 }
 387                 // Or it can be granted. This overrides the system variable
 388                 $r = q("SHOW GRANTS");
 389                 if (dbm::is_result($r)) {
 390                         foreach ($r AS $grants) {
 391                                 $grant = array_pop($grants);
 392                                 if (stristr($grant, "GRANT USAGE ON")) {
 393                                         if (preg_match("/WITH MAX_USER_CONNECTIONS (\d*)/", $grant, $match)) {
 394                                                 $max = $match[1];
 395                                         }
 396                                 }
 397                         }
 398                 }
 399         }
 400
 401         // If $max is set we will use the processlist to determine the current number of connections
 402         // The processlist only shows entries of the current user
 403         if ($max != 0) {
 404                 $r = q("SHOW PROCESSLIST");
 405                 if (!dbm::is_result($r)) {
 406                         return false;
 407                 }
 408                 $used = count($r);
 409
 410                 logger("Connection usage (user values): ".$used."/".$max, LOGGER_DEBUG);
 411
 412                 $level = ($used / $max) * 100;
 413
 414                 if ($level >= $maxlevel) {
 415                         logger("Maximum level (".$maxlevel."%) of user connections reached: ".$used."/".$max);
 416                         return true;
 417                 }
 418         }
 419
 420         // We will now check for the system values.
 421         // This limit could be reached although the user limits are fine.
 422         $r = q("SHOW VARIABLES WHERE `variable_name` = 'max_connections'");
 423         if (!dbm::is_result($r)) {
 424                 return false;
 425         }
 426         $max = intval($r[0]["Value"]);
 427         if ($max == 0) {
 428                 return false;
 429         }
 430         $r = q("SHOW STATUS WHERE `variable_name` = 'Threads_connected'");
 431         if (!dbm::is_result($r)) {
 432                 return false;
 433         }
 434         $used = intval($r[0]["Value"]);
 435         if ($used == 0) {
 436                 return false;
 437         }
 438         logger("Connection usage (system values): ".$used."/".$max, LOGGER_DEBUG);
 439
 440         $level = $used / $max * 100;
 441
 442         if ($level < $maxlevel) {
 443                 return false;
 444         }
 445         logger("Maximum level (".$level."%) of system connections reached: ".$used."/".$max);
 446         return true;
 447 }
 448
 449 /**
 450  * @brief fix the queue entry if the worker process died
 451  *
 452  */
 453 function poller_kill_stale_workers() {
 454         $r = q("SELECT `pid`, `executed`, `priority`, `parameter` FROM `workerqueue` WHERE `executed` > '%s' AND NOT `done`", dbesc(NULL_DATE));
 455
 456         if (!dbm::is_result($r)) {
 457                 // No processing here needed
 458                 return;
 459         }
 460
 461         foreach ($r AS $pid) {
 462                 if (!posix_kill($pid["pid"], 0)) {
 463                         dba::update('workerqueue', array('executed' => NULL_DATE, 'pid' => 0),
 464                                         array('pid' => $pid["pid"], 'done' => false));
 465                 } else {
 466                         // Kill long running processes
 467
 468                         // Check if the priority is in a valid range
 469                         if (!in_array($pid["priority"], array(PRIORITY_CRITICAL, PRIORITY_HIGH, PRIORITY_MEDIUM, PRIORITY_LOW, PRIORITY_NEGLIGIBLE))) {
 470                                 $pid["priority"] = PRIORITY_MEDIUM;
 471                         }
 472
 473                         // Define the maximum durations
 474                         $max_duration_defaults = array(PRIORITY_CRITICAL => 360, PRIORITY_HIGH => 10, PRIORITY_MEDIUM => 60, PRIORITY_LOW => 180, PRIORITY_NEGLIGIBLE => 360);
 475                         $max_duration = $max_duration_defaults[$pid["priority"]];
 476
 477                         $argv = json_decode($pid["parameter"]);
 478                         $argv[0] = basename($argv[0]);
 479
 480                         // How long is the process already running?
 481                         $duration = (time() - strtotime($pid["executed"])) / 60;
 482                         if ($duration > $max_duration) {
 483                                 logger("Worker process ".$pid["pid"]." (".implode(" ", $argv).") took more than ".$max_duration." minutes. It will be killed now.");
 484                                 posix_kill($pid["pid"], SIGTERM);
 485
 486                                 // We killed the stale process.
 487                                 // To avoid a blocking situation we reschedule the process at the beginning of the queue.
 488                                 // Additionally we are lowering the priority.
 489                                 dba::update('workerqueue',
 490                                                 array('executed' => NULL_DATE, 'created' => datetime_convert(), 'priority' => PRIORITY_NEGLIGIBLE, 'pid' => 0),
 491                                                 array('pid' => $pid["pid"], 'done' => false));
 492                         } else {
 493                                 logger("Worker process ".$pid["pid"]." (".implode(" ", $argv).") now runs for ".round($duration)." of ".$max_duration." allowed minutes. That's okay.", LOGGER_DEBUG);
 494                         }
 495                 }
 496         }
 497 }
 498
 499 /**
 500  * @brief Checks if the number of active workers exceeds the given limits
 501  *
 502  * @return bool Are there too much workers running?
 503  */
 504 function poller_too_much_workers() {
 505         $queues = Config::get("system", "worker_queues", 4);
 506
 507         $maxqueues = $queues;
 508
 509         $active = poller_active_workers();
 510
 511         // Decrease the number of workers at higher load
 512         $load = current_load();
 513         if ($load) {
 514                 $maxsysload = intval(Config::get("system", "maxloadavg", 50));
 515
 516                 $maxworkers = $queues;
 517
 518                 // Some magical mathemathics to reduce the workers
 519                 $exponent = 3;
 520                 $slope = $maxworkers / pow($maxsysload, $exponent);
 521                 $queues = ceil($slope * pow(max(0, $maxsysload - $load), $exponent));
 522
 523                 if (Config::get('system', 'worker_debug')) {
 524                         // Create a list of queue entries grouped by their priority
 525                         $listitem = array();
 526
 527                         // Adding all processes with no workerqueue entry
 528                         $processes = dba::p("SELECT COUNT(*) AS `running` FROM `process` WHERE NOT EXISTS
 529                                                 (SELECT id FROM `workerqueue`
 530                                                 WHERE `workerqueue`.`pid` = `process`.`pid` AND NOT `done` AND `pid` != ?)", getmypid());
 531                         if ($process = dba::fetch($processes)) {
 532                                 $listitem[0] = "0:".$process["running"];
 533                         }
 534                         dba::close($processes);
 535
 536                         // Now adding all processes with workerqueue entries
 537                         $entries = dba::p("SELECT COUNT(*) AS `entries`, `priority` FROM `workerqueue` WHERE NOT `done` GROUP BY `priority`");
 538                         while ($entry = dba::fetch($entries)) {
 539                                 $processes = dba::p("SELECT COUNT(*) AS `running` FROM `process` INNER JOIN `workerqueue` ON `workerqueue`.`pid` = `process`.`pid` AND NOT `done` WHERE `priority` = ?", $entry["priority"]);
 540                                 if ($process = dba::fetch($processes)) {
 541                                         $listitem[$entry["priority"]] = $entry["priority"].":".$process["running"]."/".$entry["entries"];
 542                                 }
 543                                 dba::close($processes);
 544                         }
 545                         dba::close($entries);
 546
 547                         $jobs_per_minute = 0;
 548
 549                         $jobs = dba::p("SELECT COUNT(*) AS `jobs` FROM `workerqueue` WHERE `done` AND `executed` > UTC_TIMESTAMP() - INTERVAL 10 MINUTE");
 550                         if ($job = dba::fetch($jobs)) {
 551                                 $jobs_per_minute = number_format($job['jobs'] / 10, 0);
 552                         }
 553                         dba::close($jobs);
 554
 555                         $processlist = ' - jpm: '.$jobs_per_minute.' ('.implode(', ', $listitem).')';
 556                 }
 557
 558                 $entries = poller_total_entries();
 559
 560                 if (Config::get("system", "worker_fastlane", false) && ($queues > 0) && ($entries > 0) && ($active >= $queues)) {
 561                         $top_priority = poller_highest_priority();
 562                         $high_running = poller_process_with_priority_active($top_priority);
 563
 564                         if (!$high_running && ($top_priority > PRIORITY_UNDEFINED) && ($top_priority < PRIORITY_NEGLIGIBLE)) {
 565                                 logger("There are jobs with priority ".$top_priority." waiting but none is executed. Open a fastlane.", LOGGER_DEBUG);
 566                                 $queues = $active + 1;
 567                         }
 568                 }
 569
 570                 logger("Load: ".$load."/".$maxsysload." - processes: ".$active."/".$entries.$processlist." - maximum: ".$queues."/".$maxqueues, LOGGER_DEBUG);
 571
 572                 // Are there fewer workers running as possible? Then fork a new one.
 573                 if (!Config::get("system", "worker_dont_fork") && ($queues > ($active + 1)) && ($entries > 1)) {
 574                         logger("Active workers: ".$active."/".$queues." Fork a new worker.", LOGGER_DEBUG);
 575                         $args = array("include/poller.php", "no_cron");
 576                         $a = get_app();
 577                         $a->proc_run($args);
 578                 }
 579         }
 580
 581         return $active >= $queues;
 582 }
 583
 584 /**
 585  * @brief Returns the number of active poller processes
 586  *
 587  * @return integer Number of active poller processes
 588  */
 589 function poller_active_workers() {
 590         $workers = q("SELECT COUNT(*) AS `processes` FROM `process` WHERE `command` = 'poller.php'");
 591
 592         return $workers[0]["processes"];
 593 }
 594
 595 /**
 596  * @brief Check if we should pass some slow processes
 597  *
 598  * When the active processes of the highest priority are using more than 2/3
 599  * of all processes, we let pass slower processes.
 600  *
 601  * @param string $highest_priority Returns the currently highest priority
 602  * @return bool We let pass a slower process than $highest_priority
 603  */
 604 function poller_passing_slow(&$highest_priority) {
 605
 606         $highest_priority = 0;
 607
 608         $r = q("SELECT `priority`
 609                 FROM `process`
 610                 INNER JOIN `workerqueue` ON `workerqueue`.`pid` = `process`.`pid` AND NOT `done`");
 611
 612         // No active processes at all? Fine
 613         if (!dbm::is_result($r)) {
 614                 return false;
 615         }
 616         $priorities = array();
 617         foreach ($r AS $line) {
 618                 $priorities[] = $line["priority"];
 619         }
 620         // Should not happen
 621         if (count($priorities) == 0) {
 622                 return false;
 623         }
 624         $highest_priority = min($priorities);
 625
 626         // The highest process is already the slowest one?
 627         // Then we quit
 628         if ($highest_priority == PRIORITY_NEGLIGIBLE) {
 629                 return false;
 630         }
 631         $high = 0;
 632         foreach ($priorities AS $priority) {
 633                 if ($priority == $highest_priority) {
 634                         ++$high;
 635                 }
 636         }
 637         logger("Highest priority: ".$highest_priority." Total processes: ".count($priorities)." Count high priority processes: ".$high, LOGGER_DEBUG);
 638         $passing_slow = (($high/count($priorities)) > (2/3));
 639
 640         if ($passing_slow) {
 641                 logger("Passing slower processes than priority ".$highest_priority, LOGGER_DEBUG);
 642         }
 643         return $passing_slow;
 644 }
 645
 646 /**
 647  * @brief Find and claim the next worker process for us
 648  *
 649  * @return boolean Have we found something?
 650  */
 651 function find_worker_processes() {
 652         // Check if we should pass some low priority process
 653         $highest_priority = 0;
 654         $found = false;
 655
 656         // The higher the number of parallel workers, the more we prefetch to prevent concurring access
 657         $limit = Config::get("system", "worker_queues", 4) * 2;
 658         $limit = Config::get('system', 'worker_fetch_limit', $limit);
 659
 660         if (poller_passing_slow($highest_priority)) {
 661                 // Are there waiting processes with a higher priority than the currently highest?
 662                 $result = dba::e("UPDATE `workerqueue` SET `executed` = ?, `pid` = ?
 663                                         WHERE `executed` <= ? AND `priority` < ? AND NOT `done`
 664                                         ORDER BY `priority`, `created` LIMIT ".intval($limit),
 665                                 datetime_convert(), getmypid(), NULL_DATE, $highest_priority);
 666                 if ($result) {
 667                         $found = (dba::affected_rows() > 0);
 668                 }
 669
 670                 if (!$found) {
 671                         // Give slower processes some processing time
 672                         $result = dba::e("UPDATE `workerqueue` SET `executed` = ?, `pid` = ?
 673                                                 WHERE `executed` <= ? AND `priority` > ? AND NOT `done`
 674                                                 ORDER BY `priority`, `created` LIMIT ".intval($limit),
 675                                         datetime_convert(), getmypid(), NULL_DATE, $highest_priority);
 676                         if ($result) {
 677                                 $found = (dba::affected_rows() > 0);
 678                         }
 679                 }
 680         }
 681
 682         // If there is no result (or we shouldn't pass lower processes) we check without priority limit
 683         if (!$found) {
 684                 $result = dba::e("UPDATE `workerqueue` SET `executed` = ?, `pid` = ? WHERE `executed` <= ? AND NOT `done` ORDER BY `priority`, `created` LIMIT ".intval($limit),
 685                                 datetime_convert(), getmypid(), NULL_DATE);
 686                 if ($result) {
 687                         $found = (dba::affected_rows() > 0);
 688                 }
 689         }
 690         return $found;
 691 }
 692
 693 /**
 694  * @brief Returns the next worker process
 695  *
 696  * @return string SQL statement
 697  */
 698 function poller_worker_process() {
 699         global $poller_db_duration, $poller_lock_duration;
 700
 701         $stamp = (float)microtime(true);
 702
 703         // There can already be jobs for us in the queue.
 704         $r = q("SELECT * FROM `workerqueue` WHERE `pid` = %d AND NOT `done`", intval(getmypid()));
 705         if (dbm::is_result($r)) {
 706                 $poller_db_duration += (microtime(true) - $stamp);
 707                 return $r;
 708         }
 709
 710         $stamp = (float)microtime(true);
 711         if (!Lock::set('poller_worker_process')) {
 712                 return false;
 713         }
 714         $poller_lock_duration = (microtime(true) - $stamp);
 715
 716         $stamp = (float)microtime(true);
 717         $found = find_worker_processes();
 718         $poller_db_duration += (microtime(true) - $stamp);
 719
 720         Lock::remove('poller_worker_process');
 721
 722         if ($found) {
 723                 $r = q("SELECT * FROM `workerqueue` WHERE `pid` = %d AND NOT `done`", intval(getmypid()));
 724         }
 725         return $r;
 726 }
 727
 728 /**
 729  * @brief Removes a workerqueue entry from the current process
 730  */
 731 function poller_unclaim_process() {
 732         $mypid = getmypid();
 733
 734         dba::update('workerqueue', array('executed' => NULL_DATE, 'pid' => 0), array('pid' => $mypid, 'done' => false));
 735 }
 736
 737 /**
 738  * @brief Call the front end worker
 739  */
 740 function call_worker() {
 741         if (!Config::get("system", "frontend_worker")) {
 742                 return;
 743         }
 744
 745         $url = App::get_baseurl()."/worker";
 746         fetch_url($url, false, $redirects, 1);
 747 }
 748
 749 /**
 750  * @brief Call the front end worker if there aren't any active
 751  */
 752 function call_worker_if_idle() {
 753         if (!Config::get("system", "frontend_worker")) {
 754                 return;
 755         }
 756
 757         // Do we have "proc_open"? Then we can fork the poller
 758         if (function_exists("proc_open")) {
 759                 // When was the last time that we called the worker?
 760                 // Less than one minute? Then we quit
 761                 if ((time() - Config::get("system", "worker_started")) < 60) {
 762                         return;
 763                 }
 764
 765                 set_config("system", "worker_started", time());
 766
 767                 // Do we have enough running workers? Then we quit here.
 768                 if (poller_too_much_workers()) {
 769                         // Cleaning dead processes
 770                         poller_kill_stale_workers();
 771                         get_app()->remove_inactive_processes();
 772
 773                         return;
 774                 }
 775
 776                 poller_run_cron();
 777
 778                 logger('Call poller', LOGGER_DEBUG);
 779
 780                 $args = array("include/poller.php", "no_cron");
 781                 $a = get_app();
 782                 $a->proc_run($args);
 783                 return;
 784         }
 785
 786         // We cannot execute background processes.
 787         // We now run the processes from the frontend.
 788         // This won't work with long running processes.
 789         poller_run_cron();
 790
 791         clear_worker_processes();
 792
 793         $workers = q("SELECT COUNT(*) AS `processes` FROM `process` WHERE `command` = 'worker.php'");
 794
 795         if ($workers[0]["processes"] == 0) {
 796                 call_worker();
 797         }
 798 }
 799
 800 /**
 801  * @brief Removes long running worker processes
 802  */
 803 function clear_worker_processes() {
 804         $timeout = Config::get("system", "frontend_worker_timeout", 10);
 805
 806         /// @todo We should clean up the corresponding workerqueue entries as well
 807         q("DELETE FROM `process` WHERE `created` < '%s' AND `command` = 'worker.php'",
 808                 dbesc(datetime_convert('UTC','UTC',"now - ".$timeout." minutes")));
 809 }
 810
 811 /**
 812  * @brief Runs the cron processes
 813  */
 814 function poller_run_cron() {
 815         logger('Add cron entries', LOGGER_DEBUG);
 816
 817         // Check for spooled items
 818         proc_run(PRIORITY_HIGH, "include/spool_post.php");
 819
 820         // Run the cron job that calls all other jobs
 821         proc_run(PRIORITY_MEDIUM, "include/cron.php");
 822
 823         // Run the cronhooks job separately from cron for being able to use a different timing
 824         proc_run(PRIORITY_MEDIUM, "include/cronhooks.php");
 825
 826         // Cleaning dead processes
 827         poller_kill_stale_workers();
 828 }
 829
 830 if (array_search(__file__,get_included_files())===0){
 831         poller_run($_SERVER["argv"],$_SERVER["argc"]);
 832
 833         poller_unclaim_process();
 834
 835         get_app()->end_process();
 836
 837         Lock::remove('poller_worker');
 838         Lock::remove('poller_worker_process');
 839
 840         killme();
 841 }