include/poller.php

   1 <?php
   2 if (!file_exists("boot.php") AND (sizeof($_SERVER["argv"]) != 0)) {
   3         $directory = dirname($_SERVER["argv"][0]);
   4
   5         if (substr($directory, 0, 1) != "/")
   6                 $directory = $_SERVER["PWD"]."/".$directory;
   7
   8         $directory = realpath($directory."/..");
   9
  10         chdir($directory);
  11 }
  12
  13 use \Friendica\Core\Config;
  14 use \Friendica\Core\PConfig;
  15
  16 require_once("boot.php");
  17
  18 function poller_run(&$argv, &$argc){
  19         global $a, $db;
  20
  21         if(is_null($a)) {
  22                 $a = new App;
  23         }
  24
  25         if(is_null($db)) {
  26                 @include(".htconfig.php");
  27                 require_once("include/dba.php");
  28                 $db = new dba($db_host, $db_user, $db_pass, $db_data);
  29                 unset($db_host, $db_user, $db_pass, $db_data);
  30         };
  31
  32         // Quit when in maintenance
  33         if (get_config('system', 'maintenance', true))
  34                 return;
  35
  36         $a->start_process();
  37
  38         $mypid = getmypid();
  39
  40         if ($a->max_processes_reached())
  41                 return;
  42
  43         if (poller_max_connections_reached())
  44                 return;
  45
  46         if (App::maxload_reached())
  47                 return;
  48
  49         // Checking the number of workers
  50         if (poller_too_much_workers()) {
  51                 poller_kill_stale_workers();
  52                 return;
  53         }
  54
  55         if(($argc <= 1) OR ($argv[1] != "no_cron")) {
  56                 // Run the cron job that calls all other jobs
  57                 proc_run(PRIORITY_MEDIUM, "include/cron.php");
  58
  59                 // Run the cronhooks job separately from cron for being able to use a different timing
  60                 proc_run(PRIORITY_MEDIUM, "include/cronhooks.php");
  61
  62                 // Cleaning dead processes
  63                 poller_kill_stale_workers();
  64         } else
  65                 // Sleep four seconds before checking for running processes again to avoid having too many workers
  66                 sleep(4);
  67
  68         // Checking number of workers
  69         if (poller_too_much_workers())
  70                 return;
  71
  72         $cooldown = Config::get("system", "worker_cooldown", 0);
  73
  74         $starttime = time();
  75
  76         while ($r = poller_worker_process()) {
  77
  78                 // Quit when in maintenance
  79                 if (get_config('system', 'maintenance', true))
  80                         return;
  81
  82                 // Constantly check the number of parallel database processes
  83                 if ($a->max_processes_reached())
  84                         return;
  85
  86                 // Constantly check the number of available database connections to let the frontend be accessible at any time
  87                 if (poller_max_connections_reached())
  88                         return;
  89
  90                 // Count active workers and compare them with a maximum value that depends on the load
  91                 if (poller_too_much_workers())
  92                         return;
  93
  94                 $upd = q("UPDATE `workerqueue` SET `executed` = '%s', `pid` = %d WHERE `id` = %d AND `pid` = 0",
  95                         dbesc(datetime_convert()),
  96                         intval($mypid),
  97                         intval($r[0]["id"]));
  98
  99                 if (!$upd) {
 100                         logger("Couldn't update queue entry ".$r[0]["id"]." - skip this execution", LOGGER_DEBUG);
 101                         continue;
 102                 }
 103
 104                 // Assure that there are no tasks executed twice
 105                 $id = q("SELECT `pid`, `executed` FROM `workerqueue` WHERE `id` = %d", intval($r[0]["id"]));
 106                 if (!$id) {
 107                         logger("Queue item ".$r[0]["id"]." vanished - skip this execution", LOGGER_DEBUG);
 108                         continue;
 109                 } elseif ((strtotime($id[0]["executed"]) <= 0) OR ($id[0]["pid"] == 0)) {
 110                         logger("Entry for queue item ".$r[0]["id"]." wasn't stored - we better stop here", LOGGER_DEBUG);
 111                         return;
 112                 } elseif ($id[0]["pid"] != $mypid) {
 113                         logger("Queue item ".$r[0]["id"]." is to be executed by process ".$id[0]["pid"]." and not by me (".$mypid.") - skip this execution", LOGGER_DEBUG);
 114                         continue;
 115                 }
 116
 117                 $argv = json_decode($r[0]["parameter"]);
 118
 119                 $argc = count($argv);
 120
 121                 // Check for existance and validity of the include file
 122                 $include = $argv[0];
 123
 124                 if (!validate_include($include)) {
 125                         logger("Include file ".$argv[0]." is not valid!");
 126                         q("DELETE FROM `workerqueue` WHERE `id` = %d", intval($r[0]["id"]));
 127                         continue;
 128                 }
 129
 130                 require_once($include);
 131
 132                 $funcname = str_replace(".php", "", basename($argv[0]))."_run";
 133
 134                 if (function_exists($funcname)) {
 135                         logger("Process ".$mypid." - Prio ".$r[0]["priority"]." - ID ".$r[0]["id"].": ".$funcname." ".$r[0]["parameter"]);
 136
 137                         // For better logging create a new process id for every worker call
 138                         // But preserve the old one for the worker
 139                         $old_process_id = $a->process_id;
 140                         $a->process_id = uniqid("wrk", true);
 141
 142                         $funcname($argv, $argc);
 143
 144                         $a->process_id = $old_process_id;
 145
 146                         if ($cooldown > 0) {
 147                                 logger("Process ".$mypid." - Prio ".$r[0]["priority"]." - ID ".$r[0]["id"].": ".$funcname." - in cooldown for ".$cooldown." seconds");
 148                                 sleep($cooldown);
 149                         }
 150
 151                         logger("Process ".$mypid." - Prio ".$r[0]["priority"]." - ID ".$r[0]["id"].": ".$funcname." - done");
 152
 153                         q("DELETE FROM `workerqueue` WHERE `id` = %d", intval($r[0]["id"]));
 154                 } else
 155                         logger("Function ".$funcname." does not exist");
 156
 157                 // Quit the poller once every hour
 158                 if (time() > ($starttime + 3600))
 159                         return;
 160         }
 161
 162 }
 163
 164 /**
 165  * @brief Checks if the number of database connections has reached a critical limit.
 166  *
 167  * @return bool Are more than 3/4 of the maximum connections used?
 168  */
 169 function poller_max_connections_reached() {
 170
 171         // Fetch the max value from the config. This is needed when the system cannot detect the correct value by itself.
 172         $max = get_config("system", "max_connections");
 173
 174         // Fetch the percentage level where the poller will get active
 175         $maxlevel = get_config("system", "max_connections_level");
 176         if ($maxlevel == 0)
 177                 $maxlevel = 75;
 178
 179         if ($max == 0) {
 180                 // the maximum number of possible user connections can be a system variable
 181                 $r = q("SHOW VARIABLES WHERE `variable_name` = 'max_user_connections'");
 182                 if ($r)
 183                         $max = $r[0]["Value"];
 184
 185                 // Or it can be granted. This overrides the system variable
 186                 $r = q("SHOW GRANTS");
 187                 if ($r)
 188                         foreach ($r AS $grants) {
 189                                 $grant = array_pop($grants);
 190                                 if (stristr($grant, "GRANT USAGE ON"))
 191                                         if (preg_match("/WITH MAX_USER_CONNECTIONS (\d*)/", $grant, $match))
 192                                                 $max = $match[1];
 193                         }
 194         }
 195
 196         // If $max is set we will use the processlist to determine the current number of connections
 197         // The processlist only shows entries of the current user
 198         if ($max != 0) {
 199                 $r = q("SHOW PROCESSLIST");
 200                 if (!$r)
 201                         return false;
 202
 203                 $used = count($r);
 204
 205                 logger("Connection usage (user values): ".$used."/".$max, LOGGER_DEBUG);
 206
 207                 $level = ($used / $max) * 100;
 208
 209                 if ($level >= $maxlevel) {
 210                         logger("Maximum level (".$maxlevel."%) of user connections reached: ".$used."/".$max);
 211                         return true;
 212                 }
 213         }
 214
 215         // We will now check for the system values.
 216         // This limit could be reached although the user limits are fine.
 217         $r = q("SHOW VARIABLES WHERE `variable_name` = 'max_connections'");
 218         if (!$r)
 219                 return false;
 220
 221         $max = intval($r[0]["Value"]);
 222         if ($max == 0)
 223                 return false;
 224
 225         $r = q("SHOW STATUS WHERE `variable_name` = 'Threads_connected'");
 226         if (!$r)
 227                 return false;
 228
 229         $used = intval($r[0]["Value"]);
 230         if ($used == 0)
 231                 return false;
 232
 233         logger("Connection usage (system values): ".$used."/".$max, LOGGER_DEBUG);
 234
 235         $level = $used / $max * 100;
 236
 237         if ($level < $maxlevel)
 238                 return false;
 239
 240         logger("Maximum level (".$level."%) of system connections reached: ".$used."/".$max);
 241         return true;
 242 }
 243
 244 /**
 245  * @brief fix the queue entry if the worker process died
 246  *
 247  */
 248 function poller_kill_stale_workers() {
 249         $r = q("SELECT `pid`, `executed`, `priority`, `parameter` FROM `workerqueue` WHERE `executed` != '0000-00-00 00:00:00'");
 250
 251         if (!dbm::is_result($r)) {
 252                 // No processing here needed
 253                 return;
 254         }
 255
 256         foreach($r AS $pid)
 257                 if (!posix_kill($pid["pid"], 0))
 258                         q("UPDATE `workerqueue` SET `executed` = '0000-00-00 00:00:00', `pid` = 0 WHERE `pid` = %d",
 259                                 intval($pid["pid"]));
 260                 else {
 261                         // Kill long running processes
 262
 263                         // Check if the priority is in a valid range
 264                         if (!in_array($pid["priority"], array(PRIORITY_CRITICAL, PRIORITY_HIGH, PRIORITY_MEDIUM, PRIORITY_LOW, PRIORITY_NEGLIGIBLE)))
 265                                 $pid["priority"] = PRIORITY_MEDIUM;
 266
 267                         // Define the maximum durations
 268                         $max_duration_defaults = array(PRIORITY_CRITICAL => 360, PRIORITY_HIGH => 10, PRIORITY_MEDIUM => 60, PRIORITY_LOW => 180, PRIORITY_NEGLIGIBLE => 360);
 269                         $max_duration = $max_duration_defaults[$pid["priority"]];
 270
 271                         $argv = json_decode($pid["parameter"]);
 272                         $argv[0] = basename($argv[0]);
 273
 274                         // How long is the process already running?
 275                         $duration = (time() - strtotime($pid["executed"])) / 60;
 276                         if ($duration > $max_duration) {
 277                                 logger("Worker process ".$pid["pid"]." (".implode(" ", $argv).") took more than ".$max_duration." minutes. It will be killed now.");
 278                                 posix_kill($pid["pid"], SIGTERM);
 279
 280                                 // We killed the stale process.
 281                                 // To avoid a blocking situation we reschedule the process at the beginning of the queue.
 282                                 // Additionally we are lowering the priority.
 283                                 q("UPDATE `workerqueue` SET `executed` = '0000-00-00 00:00:00', `created` = '%s',
 284                                                         `priority` = %d, `pid` = 0 WHERE `pid` = %d",
 285                                         dbesc(datetime_convert()),
 286                                         intval(PRIORITY_NEGLIGIBLE),
 287                                         intval($pid["pid"]));
 288                         } else
 289                                 logger("Worker process ".$pid["pid"]." (".implode(" ", $argv).") now runs for ".round($duration)." of ".$max_duration." allowed minutes. That's okay.", LOGGER_DEBUG);
 290                 }
 291 }
 292
 293 function poller_too_much_workers() {
 294
 295
 296         $queues = get_config("system", "worker_queues");
 297
 298         if ($queues == 0)
 299                 $queues = 4;
 300
 301         $maxqueues = $queues;
 302
 303         $active = poller_active_workers();
 304
 305         // Decrease the number of workers at higher load
 306         $load = current_load();
 307         if($load) {
 308                 $maxsysload = intval(get_config('system','maxloadavg'));
 309                 if($maxsysload < 1)
 310                         $maxsysload = 50;
 311
 312                 $maxworkers = $queues;
 313
 314                 // Some magical mathemathics to reduce the workers
 315                 $exponent = 3;
 316                 $slope = $maxworkers / pow($maxsysload, $exponent);
 317                 $queues = ceil($slope * pow(max(0, $maxsysload - $load), $exponent));
 318
 319                 $s = q("SELECT COUNT(*) AS `total` FROM `workerqueue` WHERE `executed` = '0000-00-00 00:00:00'");
 320                 $entries = $s[0]["total"];
 321
 322                 if (Config::get("system", "worker_fastlane", false) AND ($queues > 0) AND ($entries > 0) AND ($active >= $queues)) {
 323                         $s = q("SELECT `priority` FROM `workerqueue` WHERE `executed` = '0000-00-00 00:00:00' ORDER BY `priority` LIMIT 1");
 324                         $top_priority = $s[0]["priority"];
 325
 326                         $s = q("SELECT `id` FROM `workerqueue` WHERE `priority` <= %d AND `executed` != '0000-00-00 00:00:00' LIMIT 1",
 327                                 intval($top_priority));
 328                         $high_running = dbm::is_result($s);
 329
 330                         if (!$high_running AND ($top_priority > PRIORITY_UNDEFINED) AND ($top_priority < PRIORITY_NEGLIGIBLE)) {
 331                                 logger("There are jobs with priority ".$top_priority." waiting but none is executed. Open a fastlane.", LOGGER_DEBUG);
 332                                 $queues = $active + 1;
 333                         }
 334                 }
 335
 336                 // Create a list of queue entries grouped by their priority
 337                 $running = array(PRIORITY_CRITICAL => 0,
 338                                 PRIORITY_HIGH => 0,
 339                                 PRIORITY_MEDIUM => 0,
 340                                 PRIORITY_LOW => 0,
 341                                 PRIORITY_NEGLIGIBLE => 0);
 342
 343                 $r = q("SELECT COUNT(*) AS `running`, `priority` FROM `process` INNER JOIN `workerqueue` ON `workerqueue`.`pid` = `process`.`pid` GROUP BY `priority`");
 344                 if (dbm::is_result($r))
 345                         foreach ($r AS $process)
 346                                 $running[$process["priority"]] = $process["running"];
 347
 348                 $processlist = "";
 349                 $r = q("SELECT COUNT(*) AS `entries`, `priority` FROM `workerqueue` GROUP BY `priority`");
 350                 if (dbm::is_result($r))
 351                         foreach ($r as $entry) {
 352                                 if ($processlist != "")
 353                                         $processlist .= ", ";
 354                                 $processlist .= $entry["priority"].":".$running[$entry["priority"]]."/".$entry["entries"];
 355                         }
 356
 357                 logger("Load: ".$load."/".$maxsysload." - processes: ".$active."/".$entries." (".$processlist.") - maximum: ".$queues."/".$maxqueues, LOGGER_DEBUG);
 358
 359                 // Are there fewer workers running as possible? Then fork a new one.
 360                 if (!get_config("system", "worker_dont_fork") AND ($queues > ($active + 1)) AND ($entries > 1)) {
 361                         logger("Active workers: ".$active."/".$queues." Fork a new worker.", LOGGER_DEBUG);
 362                         $args = array("php", "include/poller.php", "no_cron");
 363                         $a = get_app();
 364                         $a->proc_run($args);
 365                 }
 366         }
 367
 368         return($active >= $queues);
 369 }
 370
 371 function poller_active_workers() {
 372         $workers = q("SELECT COUNT(*) AS `processes` FROM `process` WHERE `command` = 'poller.php'");
 373
 374         return($workers[0]["processes"]);
 375 }
 376
 377 /**
 378  * @brief Check if we should pass some slow processes
 379  *
 380  * When the active processes of the highest priority are using more than 2/3
 381  * of all processes, we let pass slower processes.
 382  *
 383  * @param string $highest_priority Returns the currently highest priority
 384  * @return bool We let pass a slower process than $highest_priority
 385  */
 386 function poller_passing_slow(&$highest_priority) {
 387
 388         $highest_priority = 0;
 389
 390         $r = q("SELECT `priority`
 391                 FROM `process`
 392                 INNER JOIN `workerqueue` ON `workerqueue`.`pid` = `process`.`pid`
 393                 WHERE `process`.`command` = 'poller.php'");
 394
 395         // No active processes at all? Fine
 396         if (!dbm::is_result($r))
 397                 return(false);
 398
 399         $priorities = array();
 400         foreach ($r AS $line)
 401                 $priorities[] = $line["priority"];
 402
 403         // Should not happen
 404         if (count($priorities) == 0)
 405                 return(false);
 406
 407         $highest_priority = min($priorities);
 408
 409         // The highest process is already the slowest one?
 410         // Then we quit
 411         if ($highest_priority == PRIORITY_NEGLIGIBLE)
 412                 return(false);
 413
 414         $high = 0;
 415         foreach ($priorities AS $priority)
 416                 if ($priority == $highest_priority)
 417                         ++$high;
 418
 419         logger("Highest priority: ".$highest_priority." Total processes: ".count($priorities)." Count high priority processes: ".$high, LOGGER_DEBUG);
 420         $passing_slow = (($high/count($priorities)) > (2/3));
 421
 422         if ($passing_slow)
 423                 logger("Passing slower processes than priority ".$highest_priority, LOGGER_DEBUG);
 424
 425         return($passing_slow);
 426 }
 427
 428 /**
 429  * @brief Returns the next worker process
 430  *
 431  * @return string SQL statement
 432  */
 433
 434 function poller_worker_process() {
 435
 436         // Check if we should pass some low priority process
 437         $highest_priority = 0;
 438
 439         if (poller_passing_slow($highest_priority)) {
 440                 // Are there waiting processes with a higher priority than the currently highest?
 441                 $r = q("SELECT * FROM `workerqueue`
 442                                 WHERE `executed` = '0000-00-00 00:00:00' AND `priority` < %d
 443                                 ORDER BY `priority`, `created` LIMIT 1", dbesc($highest_priority));
 444                 if (dbm::is_result($r))
 445                         return $r;
 446
 447                 // Give slower processes some processing time
 448                 $r = q("SELECT * FROM `workerqueue`
 449                                 WHERE `executed` = '0000-00-00 00:00:00' AND `priority` > %d
 450                                 ORDER BY `priority`, `created` LIMIT 1", dbesc($highest_priority));
 451         }
 452
 453         // If there is no result (or we shouldn't pass lower processes) we check without priority limit
 454         if (($highest_priority == 0) OR !dbm::is_result($r))
 455                 $r = q("SELECT * FROM `workerqueue` WHERE `executed` = '0000-00-00 00:00:00' ORDER BY `priority`, `created` LIMIT 1");
 456
 457         return $r;
 458 }
 459
 460 if (array_search(__file__,get_included_files())===0){
 461         poller_run($_SERVER["argv"],$_SERVER["argc"]);
 462
 463         get_app()->end_process();
 464
 465         killme();
 466 }
 467 ?>