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                         q("COMMIT");
 102                         continue;
 103                 }
 104
 105                 // Assure that there are no tasks executed twice
 106                 $id = q("SELECT `pid`, `executed` FROM `workerqueue` WHERE `id` = %d", intval($r[0]["id"]));
 107                 if (!$id) {
 108                         logger("Queue item ".$r[0]["id"]." vanished - skip this execution", LOGGER_DEBUG);
 109                         q("COMMIT");
 110                         continue;
 111                 } elseif ((strtotime($id[0]["executed"]) <= 0) OR ($id[0]["pid"] == 0)) {
 112                         logger("Entry for queue item ".$r[0]["id"]." wasn't stored - skip this execution", LOGGER_DEBUG);
 113                         q("COMMIT");
 114                         continue;
 115                 } elseif ($id[0]["pid"] != $mypid) {
 116                         logger("Queue item ".$r[0]["id"]." is to be executed by process ".$id[0]["pid"]." and not by me (".$mypid.") - skip this execution", LOGGER_DEBUG);
 117                         q("COMMIT");
 118                         continue;
 119                 }
 120                 q("COMMIT");
 121
 122                 $argv = json_decode($r[0]["parameter"]);
 123
 124                 $argc = count($argv);
 125
 126                 // Check for existance and validity of the include file
 127                 $include = $argv[0];
 128
 129                 if (!validate_include($include)) {
 130                         logger("Include file ".$argv[0]." is not valid!");
 131                         q("DELETE FROM `workerqueue` WHERE `id` = %d", intval($r[0]["id"]));
 132                         continue;
 133                 }
 134
 135                 require_once($include);
 136
 137                 $funcname = str_replace(".php", "", basename($argv[0]))."_run";
 138
 139                 if (function_exists($funcname)) {
 140                         logger("Process ".$mypid." - Prio ".$r[0]["priority"]." - ID ".$r[0]["id"].": ".$funcname." ".$r[0]["parameter"]);
 141
 142                         // For better logging create a new process id for every worker call
 143                         // But preserve the old one for the worker
 144                         $old_process_id = $a->process_id;
 145                         $a->process_id = uniqid("wrk", true);
 146
 147                         $funcname($argv, $argc);
 148
 149                         $a->process_id = $old_process_id;
 150
 151                         if ($cooldown > 0) {
 152                                 logger("Process ".$mypid." - Prio ".$r[0]["priority"]." - ID ".$r[0]["id"].": ".$funcname." - in cooldown for ".$cooldown." seconds");
 153                                 sleep($cooldown);
 154                         }
 155
 156                         logger("Process ".$mypid." - Prio ".$r[0]["priority"]." - ID ".$r[0]["id"].": ".$funcname." - done");
 157
 158                         q("DELETE FROM `workerqueue` WHERE `id` = %d", intval($r[0]["id"]));
 159                 } else
 160                         logger("Function ".$funcname." does not exist");
 161
 162                 // Quit the poller once every hour
 163                 if (time() > ($starttime + 3600))
 164                         return;
 165         }
 166
 167 }
 168
 169 /**
 170  * @brief Checks if the number of database connections has reached a critical limit.
 171  *
 172  * @return bool Are more than 3/4 of the maximum connections used?
 173  */
 174 function poller_max_connections_reached() {
 175
 176         // Fetch the max value from the config. This is needed when the system cannot detect the correct value by itself.
 177         $max = get_config("system", "max_connections");
 178
 179         // Fetch the percentage level where the poller will get active
 180         $maxlevel = get_config("system", "max_connections_level");
 181         if ($maxlevel == 0)
 182                 $maxlevel = 75;
 183
 184         if ($max == 0) {
 185                 // the maximum number of possible user connections can be a system variable
 186                 $r = q("SHOW VARIABLES WHERE `variable_name` = 'max_user_connections'");
 187                 if ($r)
 188                         $max = $r[0]["Value"];
 189
 190                 // Or it can be granted. This overrides the system variable
 191                 $r = q("SHOW GRANTS");
 192                 if ($r)
 193                         foreach ($r AS $grants) {
 194                                 $grant = array_pop($grants);
 195                                 if (stristr($grant, "GRANT USAGE ON"))
 196                                         if (preg_match("/WITH MAX_USER_CONNECTIONS (\d*)/", $grant, $match))
 197                                                 $max = $match[1];
 198                         }
 199         }
 200
 201         // If $max is set we will use the processlist to determine the current number of connections
 202         // The processlist only shows entries of the current user
 203         if ($max != 0) {
 204                 $r = q("SHOW PROCESSLIST");
 205                 if (!$r)
 206                         return false;
 207
 208                 $used = count($r);
 209
 210                 logger("Connection usage (user values): ".$used."/".$max, LOGGER_DEBUG);
 211
 212                 $level = ($used / $max) * 100;
 213
 214                 if ($level >= $maxlevel) {
 215                         logger("Maximum level (".$maxlevel."%) of user connections reached: ".$used."/".$max);
 216                         return true;
 217                 }
 218         }
 219
 220         // We will now check for the system values.
 221         // This limit could be reached although the user limits are fine.
 222         $r = q("SHOW VARIABLES WHERE `variable_name` = 'max_connections'");
 223         if (!$r)
 224                 return false;
 225
 226         $max = intval($r[0]["Value"]);
 227         if ($max == 0)
 228                 return false;
 229
 230         $r = q("SHOW STATUS WHERE `variable_name` = 'Threads_connected'");
 231         if (!$r)
 232                 return false;
 233
 234         $used = intval($r[0]["Value"]);
 235         if ($used == 0)
 236                 return false;
 237
 238         logger("Connection usage (system values): ".$used."/".$max, LOGGER_DEBUG);
 239
 240         $level = $used / $max * 100;
 241
 242         if ($level < $maxlevel)
 243                 return false;
 244
 245         logger("Maximum level (".$level."%) of system connections reached: ".$used."/".$max);
 246         return true;
 247 }
 248
 249 /**
 250  * @brief fix the queue entry if the worker process died
 251  *
 252  */
 253 function poller_kill_stale_workers() {
 254         $r = q("SELECT `pid`, `executed`, `priority`, `parameter` FROM `workerqueue` WHERE `executed` != '0000-00-00 00:00:00'");
 255
 256         if (!dbm::is_result($r)) {
 257                 // No processing here needed
 258                 return;
 259         }
 260
 261         foreach($r AS $pid)
 262                 if (!posix_kill($pid["pid"], 0))
 263                         q("UPDATE `workerqueue` SET `executed` = '0000-00-00 00:00:00', `pid` = 0 WHERE `pid` = %d",
 264                                 intval($pid["pid"]));
 265                 else {
 266                         // Kill long running processes
 267
 268                         // Check if the priority is in a valid range
 269                         if (!in_array($pid["priority"], array(PRIORITY_CRITICAL, PRIORITY_HIGH, PRIORITY_MEDIUM, PRIORITY_LOW, PRIORITY_NEGLIGIBLE)))
 270                                 $pid["priority"] = PRIORITY_MEDIUM;
 271
 272                         // Define the maximum durations
 273                         $max_duration_defaults = array(PRIORITY_CRITICAL => 360, PRIORITY_HIGH => 10, PRIORITY_MEDIUM => 60, PRIORITY_LOW => 180, PRIORITY_NEGLIGIBLE => 360);
 274                         $max_duration = $max_duration_defaults[$pid["priority"]];
 275
 276                         $argv = json_decode($pid["parameter"]);
 277                         $argv[0] = basename($argv[0]);
 278
 279                         // How long is the process already running?
 280                         $duration = (time() - strtotime($pid["executed"])) / 60;
 281                         if ($duration > $max_duration) {
 282                                 logger("Worker process ".$pid["pid"]." (".implode(" ", $argv).") took more than ".$max_duration." minutes. It will be killed now.");
 283                                 posix_kill($pid["pid"], SIGTERM);
 284
 285                                 // We killed the stale process.
 286                                 // To avoid a blocking situation we reschedule the process at the beginning of the queue.
 287                                 // Additionally we are lowering the priority.
 288                                 q("UPDATE `workerqueue` SET `executed` = '0000-00-00 00:00:00', `created` = '%s',
 289                                                         `priority` = %d, `pid` = 0 WHERE `pid` = %d",
 290                                         dbesc(datetime_convert()),
 291                                         intval(PRIORITY_NEGLIGIBLE),
 292                                         intval($pid["pid"]));
 293                         } else
 294                                 logger("Worker process ".$pid["pid"]." (".implode(" ", $argv).") now runs for ".round($duration)." of ".$max_duration." allowed minutes. That's okay.", LOGGER_DEBUG);
 295                 }
 296 }
 297
 298 function poller_too_much_workers() {
 299
 300
 301         $queues = get_config("system", "worker_queues");
 302
 303         if ($queues == 0)
 304                 $queues = 4;
 305
 306         $maxqueues = $queues;
 307
 308         $active = poller_active_workers();
 309
 310         // Decrease the number of workers at higher load
 311         $load = current_load();
 312         if($load) {
 313                 $maxsysload = intval(get_config('system','maxloadavg'));
 314                 if($maxsysload < 1)
 315                         $maxsysload = 50;
 316
 317                 $maxworkers = $queues;
 318
 319                 // Some magical mathemathics to reduce the workers
 320                 $exponent = 3;
 321                 $slope = $maxworkers / pow($maxsysload, $exponent);
 322                 $queues = ceil($slope * pow(max(0, $maxsysload - $load), $exponent));
 323
 324                 $s = q("SELECT COUNT(*) AS `total` FROM `workerqueue` WHERE `executed` = '0000-00-00 00:00:00'");
 325                 $entries = $s[0]["total"];
 326
 327                 if (Config::get("system", "worker_fastlane", false) AND ($queues > 0) AND ($entries > 0) AND ($active >= $queues)) {
 328                         $s = q("SELECT `priority` FROM `workerqueue` WHERE `executed` = '0000-00-00 00:00:00' ORDER BY `priority` LIMIT 1");
 329                         $top_priority = $s[0]["priority"];
 330
 331                         $s = q("SELECT `id` FROM `workerqueue` WHERE `priority` <= %d AND `executed` != '0000-00-00 00:00:00' LIMIT 1",
 332                                 intval($top_priority));
 333                         $high_running = dbm::is_result($s);
 334
 335                         if (!$high_running AND ($top_priority > PRIORITY_UNDEFINED) AND ($top_priority < PRIORITY_NEGLIGIBLE)) {
 336                                 logger("There are jobs with priority ".$top_priority." waiting but none is executed. Open a fastlane.", LOGGER_DEBUG);
 337                                 $queues = $active + 1;
 338                         }
 339                 }
 340
 341                 // Create a list of queue entries grouped by their priority
 342                 $running = array(PRIORITY_CRITICAL => 0,
 343                                 PRIORITY_HIGH => 0,
 344                                 PRIORITY_MEDIUM => 0,
 345                                 PRIORITY_LOW => 0,
 346                                 PRIORITY_NEGLIGIBLE => 0);
 347
 348                 $r = q("SELECT COUNT(*) AS `running`, `priority` FROM `process` INNER JOIN `workerqueue` ON `workerqueue`.`pid` = `process`.`pid` GROUP BY `priority`");
 349                 if (dbm::is_result($r))
 350                         foreach ($r AS $process)
 351                                 $running[$process["priority"]] = $process["running"];
 352
 353                 $processlist = "";
 354                 $r = q("SELECT COUNT(*) AS `entries`, `priority` FROM `workerqueue` GROUP BY `priority`");
 355                 if (dbm::is_result($r))
 356                         foreach ($r as $entry) {
 357                                 if ($processlist != "")
 358                                         $processlist .= ", ";
 359                                 $processlist .= $entry["priority"].":".$running[$entry["priority"]]."/".$entry["entries"];
 360                         }
 361
 362                 logger("Load: ".$load."/".$maxsysload." - processes: ".$active."/".$entries." (".$processlist.") - maximum: ".$queues."/".$maxqueues, LOGGER_DEBUG);
 363
 364                 // Are there fewer workers running as possible? Then fork a new one.
 365                 if (!get_config("system", "worker_dont_fork") AND ($queues > ($active + 1)) AND ($entries > 1)) {
 366                         logger("Active workers: ".$active."/".$queues." Fork a new worker.", LOGGER_DEBUG);
 367                         $args = array("php", "include/poller.php", "no_cron");
 368                         $a = get_app();
 369                         $a->proc_run($args);
 370                 }
 371         }
 372
 373         return($active >= $queues);
 374 }
 375
 376 function poller_active_workers() {
 377         $workers = q("SELECT COUNT(*) AS `processes` FROM `process` WHERE `command` = 'poller.php'");
 378
 379         return($workers[0]["processes"]);
 380 }
 381
 382 /**
 383  * @brief Check if we should pass some slow processes
 384  *
 385  * When the active processes of the highest priority are using more than 2/3
 386  * of all processes, we let pass slower processes.
 387  *
 388  * @param string $highest_priority Returns the currently highest priority
 389  * @return bool We let pass a slower process than $highest_priority
 390  */
 391 function poller_passing_slow(&$highest_priority) {
 392
 393         $highest_priority = 0;
 394
 395         $r = q("SELECT `priority`
 396                 FROM `process`
 397                 INNER JOIN `workerqueue` ON `workerqueue`.`pid` = `process`.`pid`
 398                 WHERE `process`.`command` = 'poller.php'");
 399
 400         // No active processes at all? Fine
 401         if (!dbm::is_result($r))
 402                 return(false);
 403
 404         $priorities = array();
 405         foreach ($r AS $line)
 406                 $priorities[] = $line["priority"];
 407
 408         // Should not happen
 409         if (count($priorities) == 0)
 410                 return(false);
 411
 412         $highest_priority = min($priorities);
 413
 414         // The highest process is already the slowest one?
 415         // Then we quit
 416         if ($highest_priority == PRIORITY_NEGLIGIBLE)
 417                 return(false);
 418
 419         $high = 0;
 420         foreach ($priorities AS $priority)
 421                 if ($priority == $highest_priority)
 422                         ++$high;
 423
 424         logger("Highest priority: ".$highest_priority." Total processes: ".count($priorities)." Count high priority processes: ".$high, LOGGER_DEBUG);
 425         $passing_slow = (($high/count($priorities)) > (2/3));
 426
 427         if ($passing_slow)
 428                 logger("Passing slower processes than priority ".$highest_priority, LOGGER_DEBUG);
 429
 430         return($passing_slow);
 431 }
 432
 433 /**
 434  * @brief Returns the next worker process
 435  *
 436  * @return string SQL statement
 437  */
 438
 439 function poller_worker_process() {
 440
 441         q("START TRANSACTION;");
 442
 443         // Check if we should pass some low priority process
 444         $highest_priority = 0;
 445
 446         if (poller_passing_slow($highest_priority)) {
 447                 // Are there waiting processes with a higher priority than the currently highest?
 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                 if (dbm::is_result($r))
 452                         return $r;
 453
 454                 // Give slower processes some processing time
 455                 $r = q("SELECT * FROM `workerqueue`
 456                                 WHERE `executed` = '0000-00-00 00:00:00' AND `priority` > %d
 457                                 ORDER BY `priority`, `created` LIMIT 1", dbesc($highest_priority));
 458         }
 459
 460         // If there is no result (or we shouldn't pass lower processes) we check without priority limit
 461         if (($highest_priority == 0) OR !dbm::is_result($r))
 462                 $r = q("SELECT * FROM `workerqueue` WHERE `executed` = '0000-00-00 00:00:00' ORDER BY `priority`, `created` LIMIT 1");
 463
 464         return $r;
 465 }
 466
 467 if (array_search(__file__,get_included_files())===0){
 468         poller_run($_SERVER["argv"],$_SERVER["argc"]);
 469
 470         get_app()->end_process();
 471
 472         killme();
 473 }
 474 ?>