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, $poller_db_duration;
  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         $starttime = time();
  89
  90         // We fetch the next queue entry that is about to be executed
  91         while ($r = poller_worker_process()) {
  92
  93                 $refetched = false;
  94
  95                 foreach ($r AS $entry) {
  96                         // Assure that the priority is an integer value
  97                         $entry['priority'] = (int)$entry['priority'];
  98
  99                         // The work will be done
 100                         if (!poller_execute($entry)) {
 101                                 logger('Process execution failed, quitting.', LOGGER_DEBUG);
 102                                 return;
 103                         }
 104
 105                         // If possible we will fetch new jobs for this worker
 106                         if (!$refetched && Lock::set('poller_worker_process', 0)) {
 107                                 $stamp = (float)microtime(true);
 108                                 $refetched = find_worker_processes();
 109                                 $poller_db_duration += (microtime(true) - $stamp);
 110                                 Lock::remove('poller_worker_process');
 111                         }
 112                 }
 113
 114                 // To avoid the quitting of multiple pollers only one poller at a time will execute the check
 115                 if (Lock::set('poller_worker', 0)) {
 116                         $stamp = (float)microtime(true);
 117                         // Count active workers and compare them with a maximum value that depends on the load
 118                         if (poller_too_much_workers()) {
 119                                 logger('Active worker limit reached, quitting.', LOGGER_DEBUG);
 120                                 return;
 121                         }
 122
 123                         // Check free memory
 124                         if ($a->min_memory_reached()) {
 125                                 logger('Memory limit reached, quitting.', LOGGER_DEBUG);
 126                                 return;
 127                         }
 128                         Lock::remove('poller_worker');
 129                         $poller_db_duration += (microtime(true) - $stamp);
 130                 }
 131
 132                 // Quit the poller once every 5 minutes
 133                 if (time() > ($starttime + 300)) {
 134                         logger('Process lifetime reached, quitting.', LOGGER_DEBUG);
 135                         return;
 136                 }
 137         }
 138         logger("Couldn't select a workerqueue entry, quitting.", LOGGER_DEBUG);
 139 }
 140
 141 /**
 142  * @brief Returns the number of non executed entries in the worker queue
 143  *
 144  * @return integer Number of non executed entries in the worker queue
 145  */
 146 function poller_total_entries() {
 147         $s = q("SELECT COUNT(*) AS `total` FROM `workerqueue` WHERE `executed` <= '%s' AND NOT `done`", dbesc(NULL_DATE));
 148         if (dbm::is_result($s)) {
 149                 return $s[0]["total"];
 150         } else {
 151                 return 0;
 152         }
 153 }
 154
 155 /**
 156  * @brief Returns the highest priority in the worker queue that isn't executed
 157  *
 158  * @return integer Number of active poller processes
 159  */
 160 function poller_highest_priority() {
 161         $s = q("SELECT `priority` FROM `workerqueue` WHERE `executed` <= '%s' AND NOT `done` ORDER BY `priority` LIMIT 1", dbesc(NULL_DATE));
 162         if (dbm::is_result($s)) {
 163                 return $s[0]["priority"];
 164         } else {
 165                 return 0;
 166         }
 167 }
 168
 169 /**
 170  * @brief Returns if a process with the given priority is running
 171  *
 172  * @param integer $priority The priority that should be checked
 173  *
 174  * @return integer Is there a process running with that priority?
 175  */
 176 function poller_process_with_priority_active($priority) {
 177         $s = q("SELECT `id` FROM `workerqueue` WHERE `priority` <= %d AND `executed` > '%s' AND NOT `done` LIMIT 1",
 178                         intval($priority), dbesc(NULL_DATE));
 179         return dbm::is_result($s);
 180 }
 181
 182 /**
 183  * @brief Execute a worker entry
 184  *
 185  * @param array $queue Workerqueue entry
 186  *
 187  * @return boolean "true" if further processing should be stopped
 188  */
 189 function poller_execute($queue) {
 190         global $poller_db_duration, $poller_last_update;
 191
 192         $a = get_app();
 193
 194         $mypid = getmypid();
 195
 196         // Quit when in maintenance
 197         if (Config::get('system', 'maintenance', true)) {
 198                 logger("Maintenance mode - quit process ".$mypid, LOGGER_DEBUG);
 199                 return false;
 200         }
 201
 202         // Constantly check the number of parallel database processes
 203         if ($a->max_processes_reached()) {
 204                 logger("Max processes reached for process ".$mypid, LOGGER_DEBUG);
 205                 return false;
 206         }
 207
 208         // Constantly check the number of available database connections to let the frontend be accessible at any time
 209         if (poller_max_connections_reached()) {
 210                 logger("Max connection reached for process ".$mypid, LOGGER_DEBUG);
 211                 return false;
 212         }
 213
 214         $argv = json_decode($queue["parameter"]);
 215
 216         // Check for existance and validity of the include file
 217         $include = $argv[0];
 218
 219         if (!validate_include($include)) {
 220                 logger("Include file ".$argv[0]." is not valid!");
 221                 dba::delete('workerqueue', array('id' => $queue["id"]));
 222                 return true;
 223         }
 224
 225         require_once($include);
 226
 227         $funcname = str_replace(".php", "", basename($argv[0]))."_run";
 228
 229         if (function_exists($funcname)) {
 230
 231                 // We constantly update the "executed" date every minute to avoid being killed to soon
 232                 if (!isset($poller_last_update)) {
 233                         $poller_last_update = strtotime($queue["executed"]);
 234                 }
 235
 236                 $age = (time() - $poller_last_update) / 60;
 237                 $poller_last_update = time();
 238
 239                 if ($age > 1) {
 240                         $stamp = (float)microtime(true);
 241                         dba::update('workerqueue', array('executed' => datetime_convert()), array('pid' => $mypid, 'done' => false));
 242                         $poller_db_duration += (microtime(true) - $stamp);
 243                 }
 244
 245                 poller_exec_function($queue, $funcname, $argv);
 246
 247                 $stamp = (float)microtime(true);
 248                 dba::update('workerqueue', array('done' => true), array('id' => $queue["id"]));
 249                 $poller_db_duration = (microtime(true) - $stamp);
 250         } else {
 251                 logger("Function ".$funcname." does not exist");
 252                 dba::delete('workerqueue', array('id' => $queue["id"]));
 253         }
 254
 255         return true;
 256 }
 257
 258 /**
 259  * @brief Execute a function from the queue
 260  *
 261  * @param array $queue Workerqueue entry
 262  * @param string $funcname name of the function
 263  * @param array $argv Array of values to be passed to the function
 264  */
 265 function poller_exec_function($queue, $funcname, $argv) {
 266         global $poller_up_start, $poller_db_duration, $poller_lock_duration;
 267
 268         $a = get_app();
 269
 270         $mypid = getmypid();
 271
 272         $argc = count($argv);
 273
 274         logger("Process ".$mypid." - Prio ".$queue["priority"]." - ID ".$queue["id"].": ".$funcname." ".$queue["parameter"]);
 275
 276         $stamp = (float)microtime(true);
 277
 278         // We use the callstack here to analyze the performance of executed worker entries.
 279         // For this reason the variables have to be initialized.
 280         if (Config::get("system", "profiler")) {
 281                 $a->performance["start"] = microtime(true);
 282                 $a->performance["database"] = 0;
 283                 $a->performance["database_write"] = 0;
 284                 $a->performance["network"] = 0;
 285                 $a->performance["file"] = 0;
 286                 $a->performance["rendering"] = 0;
 287                 $a->performance["parser"] = 0;
 288                 $a->performance["marktime"] = 0;
 289                 $a->performance["markstart"] = microtime(true);
 290                 $a->callstack = array();
 291         }
 292
 293         // For better logging create a new process id for every worker call
 294         // But preserve the old one for the worker
 295         $old_process_id = $a->process_id;
 296         $a->process_id = uniqid("wrk", true);
 297         $a->queue = $queue;
 298
 299         $up_duration = number_format(microtime(true) - $poller_up_start, 3);
 300
 301         $funcname($argv, $argc);
 302
 303         $a->process_id = $old_process_id;
 304         unset($a->queue);
 305
 306         $duration = number_format(microtime(true) - $stamp, 3);
 307
 308         $poller_up_start = microtime(true);
 309
 310         /* With these values we can analyze how effective the worker is.
 311          * The database and rest time should be low since this is the unproductive time.
 312          * The execution time is the productive time.
 313          * By changing parameters like the maximum number of workers we can check the effectivness.
 314         */
 315         logger('DB: '.number_format($poller_db_duration, 2).
 316                 ' - Lock: '.number_format($poller_lock_duration, 2).
 317                 ' - Rest: '.number_format($up_duration - $poller_db_duration - $poller_lock_duration, 2).
 318                 ' - Execution: '.number_format($duration, 2), LOGGER_DEBUG);
 319         $poller_lock_duration = 0;
 320
 321         if ($duration > 3600) {
 322                 logger("Prio ".$queue["priority"].": ".$queue["parameter"]." - longer than 1 hour (".round($duration/60, 3).")", LOGGER_DEBUG);
 323         } elseif ($duration > 600) {
 324                 logger("Prio ".$queue["priority"].": ".$queue["parameter"]." - longer than 10 minutes (".round($duration/60, 3).")", LOGGER_DEBUG);
 325         } elseif ($duration > 300) {
 326                 logger("Prio ".$queue["priority"].": ".$queue["parameter"]." - longer than 5 minutes (".round($duration/60, 3).")", LOGGER_DEBUG);
 327         } elseif ($duration > 120) {
 328                 logger("Prio ".$queue["priority"].": ".$queue["parameter"]." - longer than 2 minutes (".round($duration/60, 3).")", LOGGER_DEBUG);
 329         }
 330
 331         logger("Process ".$mypid." - Prio ".$queue["priority"]." - ID ".$queue["id"].": ".$funcname." - done in ".$duration." seconds.");
 332
 333         // Write down the performance values into the log
 334         if (Config::get("system", "profiler")) {
 335                 $duration = microtime(true)-$a->performance["start"];
 336
 337                 if (Config::get("rendertime", "callstack")) {
 338                         if (isset($a->callstack["database"])) {
 339                                 $o = "\nDatabase Read:\n";
 340                                 foreach ($a->callstack["database"] AS $func => $time) {
 341                                         $time = round($time, 3);
 342                                         if ($time > 0) {
 343                                                 $o .= $func.": ".$time."\n";
 344                                         }
 345                                 }
 346                         }
 347                         if (isset($a->callstack["database_write"])) {
 348                                 $o .= "\nDatabase Write:\n";
 349                                 foreach ($a->callstack["database_write"] AS $func => $time) {
 350                                         $time = round($time, 3);
 351                                         if ($time > 0) {
 352                                                 $o .= $func.": ".$time."\n";
 353                                         }
 354                                 }
 355                         }
 356                         if (isset($a->callstack["network"])) {
 357                                 $o .= "\nNetwork:\n";
 358                                 foreach ($a->callstack["network"] AS $func => $time) {
 359                                         $time = round($time, 3);
 360                                         if ($time > 0) {
 361                                                 $o .= $func.": ".$time."\n";
 362                                         }
 363                                 }
 364                         }
 365                 } else {
 366                         $o = '';
 367                 }
 368
 369                 logger("ID ".$queue["id"].": ".$funcname.": ".sprintf("DB: %s/%s, Net: %s, I/O: %s, Other: %s, Total: %s".$o,
 370                         number_format($a->performance["database"] - $a->performance["database_write"], 2),
 371                         number_format($a->performance["database_write"], 2),
 372                         number_format($a->performance["network"], 2),
 373                         number_format($a->performance["file"], 2),
 374                         number_format($duration - ($a->performance["database"] + $a->performance["network"] + $a->performance["file"]), 2),
 375                         number_format($duration, 2)),
 376                         LOGGER_DEBUG);
 377         }
 378
 379         $cooldown = Config::get("system", "worker_cooldown", 0);
 380
 381         if ($cooldown > 0) {
 382                 logger("Process ".$mypid." - Prio ".$queue["priority"]." - ID ".$queue["id"].": ".$funcname." - in cooldown for ".$cooldown." seconds");
 383                 sleep($cooldown);
 384         }
 385 }
 386
 387 /**
 388  * @brief Checks if the number of database connections has reached a critical limit.
 389  *
 390  * @return bool Are more than 3/4 of the maximum connections used?
 391  */
 392 function poller_max_connections_reached() {
 393
 394         // Fetch the max value from the config. This is needed when the system cannot detect the correct value by itself.
 395         $max = Config::get("system", "max_connections");
 396
 397         // Fetch the percentage level where the poller will get active
 398         $maxlevel = Config::get("system", "max_connections_level", 75);
 399
 400         if ($max == 0) {
 401                 // the maximum number of possible user connections can be a system variable
 402                 $r = q("SHOW VARIABLES WHERE `variable_name` = 'max_user_connections'");
 403                 if (dbm::is_result($r)) {
 404                         $max = $r[0]["Value"];
 405                 }
 406                 // Or it can be granted. This overrides the system variable
 407                 $r = q("SHOW GRANTS");
 408                 if (dbm::is_result($r)) {
 409                         foreach ($r AS $grants) {
 410                                 $grant = array_pop($grants);
 411                                 if (stristr($grant, "GRANT USAGE ON")) {
 412                                         if (preg_match("/WITH MAX_USER_CONNECTIONS (\d*)/", $grant, $match)) {
 413                                                 $max = $match[1];
 414                                         }
 415                                 }
 416                         }
 417                 }
 418         }
 419
 420         // If $max is set we will use the processlist to determine the current number of connections
 421         // The processlist only shows entries of the current user
 422         if ($max != 0) {
 423                 $r = q("SHOW PROCESSLIST");
 424                 if (!dbm::is_result($r)) {
 425                         return false;
 426                 }
 427                 $used = count($r);
 428
 429                 logger("Connection usage (user values): ".$used."/".$max, LOGGER_DEBUG);
 430
 431                 $level = ($used / $max) * 100;
 432
 433                 if ($level >= $maxlevel) {
 434                         logger("Maximum level (".$maxlevel."%) of user connections reached: ".$used."/".$max);
 435                         return true;
 436                 }
 437         }
 438
 439         // We will now check for the system values.
 440         // This limit could be reached although the user limits are fine.
 441         $r = q("SHOW VARIABLES WHERE `variable_name` = 'max_connections'");
 442         if (!dbm::is_result($r)) {
 443                 return false;
 444         }
 445         $max = intval($r[0]["Value"]);
 446         if ($max == 0) {
 447                 return false;
 448         }
 449         $r = q("SHOW STATUS WHERE `variable_name` = 'Threads_connected'");
 450         if (!dbm::is_result($r)) {
 451                 return false;
 452         }
 453         $used = intval($r[0]["Value"]);
 454         if ($used == 0) {
 455                 return false;
 456         }
 457         logger("Connection usage (system values): ".$used."/".$max, LOGGER_DEBUG);
 458
 459         $level = $used / $max * 100;
 460
 461         if ($level < $maxlevel) {
 462                 return false;
 463         }
 464         logger("Maximum level (".$level."%) of system connections reached: ".$used."/".$max);
 465         return true;
 466 }
 467
 468 /**
 469  * @brief fix the queue entry if the worker process died
 470  *
 471  */
 472 function poller_kill_stale_workers() {
 473         $entries = dba::p("SELECT `pid`, `executed`, `priority`, `parameter` FROM `workerqueue` WHERE `executed` > ? AND NOT `done` AND `pid` != 0", NULL_DATE);
 474
 475         while ($entry = dba::fetch($entries)) {
 476                 if (!posix_kill($entry["pid"], 0)) {
 477                         dba::update('workerqueue', array('executed' => NULL_DATE, 'pid' => 0),
 478                                         array('pid' => $entry["pid"], 'done' => false));
 479                 } else {
 480                         // Kill long running processes
 481                         // Check if the priority is in a valid range
 482                         if (!in_array($entry["priority"], array(PRIORITY_CRITICAL, PRIORITY_HIGH, PRIORITY_MEDIUM, PRIORITY_LOW, PRIORITY_NEGLIGIBLE))) {
 483                                 $entry["priority"] = PRIORITY_MEDIUM;
 484                         }
 485
 486                         // Define the maximum durations
 487                         $max_duration_defaults = array(PRIORITY_CRITICAL => 720, PRIORITY_HIGH => 10, PRIORITY_MEDIUM => 60, PRIORITY_LOW => 180, PRIORITY_NEGLIGIBLE => 720);
 488                         $max_duration = $max_duration_defaults[$entry["priority"]];
 489
 490                         $argv = json_decode($entry["parameter"]);
 491                         $argv[0] = basename($argv[0]);
 492
 493                         // How long is the process already running?
 494                         $duration = (time() - strtotime($entry["executed"])) / 60;
 495                         if ($duration > $max_duration) {
 496                                 logger("Worker process ".$entry["pid"]." (".implode(" ", $argv).") took more than ".$max_duration." minutes. It will be killed now.");
 497                                 posix_kill($entry["pid"], SIGTERM);
 498
 499                                 // We killed the stale process.
 500                                 // To avoid a blocking situation we reschedule the process at the beginning of the queue.
 501                                 // Additionally we are lowering the priority. (But not PRIORITY_CRITICAL)
 502                                 if ($entry["priority"] == PRIORITY_HIGH) {
 503                                         $new_priority = PRIORITY_MEDIUM;
 504                                 } elseif ($entry["priority"] == PRIORITY_MEDIUM) {
 505                                         $new_priority = PRIORITY_LOW;
 506                                 } elseif ($entry["priority"] != PRIORITY_CRITICAL) {
 507                                         $new_priority = PRIORITY_NEGLIGIBLE;
 508                                 }
 509                                 dba::update('workerqueue',
 510                                                 array('executed' => NULL_DATE, 'created' => datetime_convert(), 'priority' => $new_priority, 'pid' => 0),
 511                                                 array('pid' => $entry["pid"], 'done' => false));
 512                         } else {
 513                                 logger("Worker process ".$entry["pid"]." (".implode(" ", $argv).") now runs for ".round($duration)." of ".$max_duration." allowed minutes. That's okay.", LOGGER_DEBUG);
 514                         }
 515                 }
 516         }
 517 }
 518
 519 /**
 520  * @brief Checks if the number of active workers exceeds the given limits
 521  *
 522  * @return bool Are there too much workers running?
 523  */
 524 function poller_too_much_workers() {
 525         $queues = Config::get("system", "worker_queues", 4);
 526
 527         $maxqueues = $queues;
 528
 529         $active = poller_active_workers();
 530
 531         // Decrease the number of workers at higher load
 532         $load = current_load();
 533         if ($load) {
 534                 $maxsysload = intval(Config::get("system", "maxloadavg", 50));
 535
 536                 $maxworkers = $queues;
 537
 538                 // Some magical mathemathics to reduce the workers
 539                 $exponent = 3;
 540                 $slope = $maxworkers / pow($maxsysload, $exponent);
 541                 $queues = ceil($slope * pow(max(0, $maxsysload - $load), $exponent));
 542
 543                 if (Config::get('system', 'worker_debug')) {
 544                         // Create a list of queue entries grouped by their priority
 545                         $listitem = array();
 546
 547                         // Adding all processes with no workerqueue entry
 548                         $processes = dba::p("SELECT COUNT(*) AS `running` FROM `process` WHERE NOT EXISTS
 549                                                 (SELECT id FROM `workerqueue`
 550                                                 WHERE `workerqueue`.`pid` = `process`.`pid` AND NOT `done` AND `pid` != ?)", getmypid());
 551                         if ($process = dba::fetch($processes)) {
 552                                 $listitem[0] = "0:".$process["running"];
 553                         }
 554                         dba::close($processes);
 555
 556                         // Now adding all processes with workerqueue entries
 557                         $entries = dba::p("SELECT COUNT(*) AS `entries`, `priority` FROM `workerqueue` WHERE NOT `done` GROUP BY `priority`");
 558                         while ($entry = dba::fetch($entries)) {
 559                                 $processes = dba::p("SELECT COUNT(*) AS `running` FROM `process` INNER JOIN `workerqueue` ON `workerqueue`.`pid` = `process`.`pid` AND NOT `done` WHERE `priority` = ?", $entry["priority"]);
 560                                 if ($process = dba::fetch($processes)) {
 561                                         $listitem[$entry["priority"]] = $entry["priority"].":".$process["running"]."/".$entry["entries"];
 562                                 }
 563                                 dba::close($processes);
 564                         }
 565                         dba::close($entries);
 566
 567                         $intervals = array(1, 10, 60);
 568                         $jobs_per_minute = array();
 569                         foreach ($intervals AS $interval) {
 570                                 $jobs = dba::p("SELECT COUNT(*) AS `jobs` FROM `workerqueue` WHERE `done` AND `executed` > UTC_TIMESTAMP() - INTERVAL ".intval($interval)." MINUTE");
 571                                 if ($job = dba::fetch($jobs)) {
 572                                         $jobs_per_minute[$interval] = number_format($job['jobs'] / $interval, 0);
 573                                 }
 574                                 dba::close($jobs);
 575                         }
 576                         $processlist = ' - jpm: '.implode('/', $jobs_per_minute).' ('.implode(', ', $listitem).')';
 577                 }
 578
 579                 $entries = poller_total_entries();
 580
 581                 if (Config::get("system", "worker_fastlane", false) && ($queues > 0) && ($entries > 0) && ($active >= $queues)) {
 582                         $top_priority = poller_highest_priority();
 583                         $high_running = poller_process_with_priority_active($top_priority);
 584
 585                         if (!$high_running && ($top_priority > PRIORITY_UNDEFINED) && ($top_priority < PRIORITY_NEGLIGIBLE)) {
 586                                 logger("There are jobs with priority ".$top_priority." waiting but none is executed. Open a fastlane.", LOGGER_DEBUG);
 587                                 $queues = $active + 1;
 588                         }
 589                 }
 590
 591                 logger("Load: ".$load."/".$maxsysload." - processes: ".$active."/".$entries.$processlist." - maximum: ".$queues."/".$maxqueues, LOGGER_DEBUG);
 592
 593                 // Are there fewer workers running as possible? Then fork a new one.
 594                 if (!Config::get("system", "worker_dont_fork") && ($queues > ($active + 1)) && ($entries > 1)) {
 595                         logger("Active workers: ".$active."/".$queues." Fork a new worker.", LOGGER_DEBUG);
 596                         $args = array("include/poller.php", "no_cron");
 597                         get_app()->proc_run($args);
 598                 }
 599         }
 600
 601         return $active >= $queues;
 602 }
 603
 604 /**
 605  * @brief Returns the number of active poller processes
 606  *
 607  * @return integer Number of active poller processes
 608  */
 609 function poller_active_workers() {
 610         $workers = q("SELECT COUNT(*) AS `processes` FROM `process` WHERE `command` = 'poller.php'");
 611
 612         return $workers[0]["processes"];
 613 }
 614
 615 /**
 616  * @brief Check if we should pass some slow processes
 617  *
 618  * When the active processes of the highest priority are using more than 2/3
 619  * of all processes, we let pass slower processes.
 620  *
 621  * @param string $highest_priority Returns the currently highest priority
 622  * @return bool We let pass a slower process than $highest_priority
 623  */
 624 function poller_passing_slow(&$highest_priority) {
 625
 626         $highest_priority = 0;
 627
 628         $r = q("SELECT `priority`
 629                 FROM `process`
 630                 INNER JOIN `workerqueue` ON `workerqueue`.`pid` = `process`.`pid` AND NOT `done`");
 631
 632         // No active processes at all? Fine
 633         if (!dbm::is_result($r)) {
 634                 return false;
 635         }
 636         $priorities = array();
 637         foreach ($r AS $line) {
 638                 $priorities[] = $line["priority"];
 639         }
 640         // Should not happen
 641         if (count($priorities) == 0) {
 642                 return false;
 643         }
 644         $highest_priority = min($priorities);
 645
 646         // The highest process is already the slowest one?
 647         // Then we quit
 648         if ($highest_priority == PRIORITY_NEGLIGIBLE) {
 649                 return false;
 650         }
 651         $high = 0;
 652         foreach ($priorities AS $priority) {
 653                 if ($priority == $highest_priority) {
 654                         ++$high;
 655                 }
 656         }
 657         logger("Highest priority: ".$highest_priority." Total processes: ".count($priorities)." Count high priority processes: ".$high, LOGGER_DEBUG);
 658         $passing_slow = (($high/count($priorities)) > (2/3));
 659
 660         if ($passing_slow) {
 661                 logger("Passing slower processes than priority ".$highest_priority, LOGGER_DEBUG);
 662         }
 663         return $passing_slow;
 664 }
 665
 666 /**
 667  * @brief Find and claim the next worker process for us
 668  *
 669  * @return boolean Have we found something?
 670  */
 671 function find_worker_processes() {
 672
 673         $mypid = getmypid();
 674
 675         // Check if we should pass some low priority process
 676         $highest_priority = 0;
 677         $found = false;
 678
 679         // The higher the number of parallel workers, the more we prefetch to prevent concurring access
 680         $limit = Config::get("system", "worker_queues", 4);
 681         $limit = Config::get('system', 'worker_fetch_limit', $limit);
 682
 683         if (poller_passing_slow($highest_priority)) {
 684                 // Are there waiting processes with a higher priority than the currently highest?
 685                 $result = dba::p("SELECT `id` FROM `workerqueue`
 686                                         WHERE `executed` <= ? AND `priority` < ? AND NOT `done`
 687                                         ORDER BY `priority`, `created` LIMIT ".intval($limit),
 688                                 NULL_DATE, $highest_priority);
 689
 690                 while ($id = dba::fetch($result)) {
 691                         $ids[] = $id["id"];
 692                 }
 693                 dba::close($result);
 694
 695                 $found = (count($ids) > 0);
 696
 697                 if (!$found) {
 698                         // Give slower processes some processing time
 699                         $result = dba::p("SELECT `id` FROM `workerqueue`
 700                                                 WHERE `executed` <= ? AND `priority` > ? AND NOT `done`
 701                                                 ORDER BY `priority`, `created` LIMIT ".intval($limit),
 702                                         NULL_DATE, $highest_priority);
 703
 704                         while ($id = dba::fetch($result)) {
 705                                 $ids[] = $id["id"];
 706                         }
 707                         dba::close($result);
 708
 709                         $found = (count($ids) > 0);
 710                 }
 711         }
 712
 713         // If there is no result (or we shouldn't pass lower processes) we check without priority limit
 714         if (!$found) {
 715                 $result = dba::p("SELECT `id` FROM `workerqueue` WHERE `executed` <= ? AND NOT `done` ORDER BY `priority`, `created` LIMIT ".intval($limit), NULL_DATE);
 716
 717                 while ($id = dba::fetch($result)) {
 718                         $ids[] = $id["id"];
 719                 }
 720                 dba::close($result);
 721
 722                 $found = (count($ids) > 0);
 723         }
 724
 725         if ($found) {
 726                 $sql = "UPDATE `workerqueue` SET `executed` = ?, `pid` = ? WHERE `id` IN (".substr(str_repeat("?, ", count($ids)), 0, -2).") AND `pid` = 0 AND NOT `done`;";
 727                 array_unshift($ids, datetime_convert(), $mypid);
 728                 dba::e($sql, $ids);
 729         }
 730
 731         return $found;
 732 }
 733
 734 /**
 735  * @brief Returns the next worker process
 736  *
 737  * @return string SQL statement
 738  */
 739 function poller_worker_process() {
 740         global $poller_db_duration, $poller_lock_duration;
 741
 742         $stamp = (float)microtime(true);
 743
 744         // There can already be jobs for us in the queue.
 745         $r = q("SELECT * FROM `workerqueue` WHERE `pid` = %d AND NOT `done`", intval(getmypid()));
 746         if (dbm::is_result($r)) {
 747                 $poller_db_duration += (microtime(true) - $stamp);
 748                 return $r;
 749         }
 750
 751         $stamp = (float)microtime(true);
 752         if (!Lock::set('poller_worker_process')) {
 753                 return false;
 754         }
 755         $poller_lock_duration = (microtime(true) - $stamp);
 756
 757         $stamp = (float)microtime(true);
 758         $found = find_worker_processes();
 759         $poller_db_duration += (microtime(true) - $stamp);
 760
 761         Lock::remove('poller_worker_process');
 762
 763         if ($found) {
 764                 $r = q("SELECT * FROM `workerqueue` WHERE `pid` = %d AND NOT `done`", intval(getmypid()));
 765         }
 766         return $r;
 767 }
 768
 769 /**
 770  * @brief Removes a workerqueue entry from the current process
 771  */
 772 function poller_unclaim_process() {
 773         $mypid = getmypid();
 774
 775         dba::update('workerqueue', array('executed' => NULL_DATE, 'pid' => 0), array('pid' => $mypid, 'done' => false));
 776 }
 777
 778 /**
 779  * @brief Call the front end worker
 780  */
 781 function call_worker() {
 782         if (!Config::get("system", "frontend_worker")) {
 783                 return;
 784         }
 785
 786         $url = App::get_baseurl()."/worker";
 787         fetch_url($url, false, $redirects, 1);
 788 }
 789
 790 /**
 791  * @brief Call the front end worker if there aren't any active
 792  */
 793 function call_worker_if_idle() {
 794         if (!Config::get("system", "frontend_worker")) {
 795                 return;
 796         }
 797
 798         // Do we have "proc_open"? Then we can fork the poller
 799         if (function_exists("proc_open")) {
 800                 // When was the last time that we called the worker?
 801                 // Less than one minute? Then we quit
 802                 if ((time() - Config::get("system", "worker_started")) < 60) {
 803                         return;
 804                 }
 805
 806                 set_config("system", "worker_started", time());
 807
 808                 // Do we have enough running workers? Then we quit here.
 809                 if (poller_too_much_workers()) {
 810                         // Cleaning dead processes
 811                         poller_kill_stale_workers();
 812                         get_app()->remove_inactive_processes();
 813
 814                         return;
 815                 }
 816
 817                 poller_run_cron();
 818
 819                 logger('Call poller', LOGGER_DEBUG);
 820
 821                 $args = array("include/poller.php", "no_cron");
 822                 get_app()->proc_run($args);
 823                 return;
 824         }
 825
 826         // We cannot execute background processes.
 827         // We now run the processes from the frontend.
 828         // This won't work with long running processes.
 829         poller_run_cron();
 830
 831         clear_worker_processes();
 832
 833         $workers = q("SELECT COUNT(*) AS `processes` FROM `process` WHERE `command` = 'worker.php'");
 834
 835         if ($workers[0]["processes"] == 0) {
 836                 call_worker();
 837         }
 838 }
 839
 840 /**
 841  * @brief Removes long running worker processes
 842  */
 843 function clear_worker_processes() {
 844         $timeout = Config::get("system", "frontend_worker_timeout", 10);
 845
 846         /// @todo We should clean up the corresponding workerqueue entries as well
 847         q("DELETE FROM `process` WHERE `created` < '%s' AND `command` = 'worker.php'",
 848                 dbesc(datetime_convert('UTC','UTC',"now - ".$timeout." minutes")));
 849 }
 850
 851 /**
 852  * @brief Runs the cron processes
 853  */
 854 function poller_run_cron() {
 855         logger('Add cron entries', LOGGER_DEBUG);
 856
 857         // Check for spooled items
 858         proc_run(PRIORITY_HIGH, "include/spool_post.php");
 859
 860         // Run the cron job that calls all other jobs
 861         proc_run(PRIORITY_MEDIUM, "include/cron.php");
 862
 863         // Run the cronhooks job separately from cron for being able to use a different timing
 864         proc_run(PRIORITY_MEDIUM, "include/cronhooks.php");
 865
 866         // Cleaning dead processes
 867         poller_kill_stale_workers();
 868 }
 869
 870 if (array_search(__file__,get_included_files())===0){
 871         poller_run($_SERVER["argv"],$_SERVER["argc"]);
 872
 873         poller_unclaim_process();
 874
 875         get_app()->end_process();
 876
 877         killme();
 878 }