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         $a->start_process();
  33
  34         $mypid = getmypid();
  35
  36         if ($a->max_processes_reached())
  37                 return;
  38
  39         if (poller_max_connections_reached())
  40                 return;
  41
  42         if (App::maxload_reached())
  43                 return;
  44
  45         // Checking the number of workers
  46         if (poller_too_much_workers()) {
  47                 poller_kill_stale_workers();
  48                 return;
  49         }
  50
  51         if(($argc <= 1) OR ($argv[1] != "no_cron")) {
  52                 // Run the cron job that calls all other jobs
  53                 proc_run(PRIORITY_MEDIUM, "include/cron.php");
  54
  55                 // Run the cronhooks job separately from cron for being able to use a different timing
  56                 proc_run(PRIORITY_MEDIUM, "include/cronhooks.php");
  57
  58                 // Cleaning dead processes
  59                 poller_kill_stale_workers();
  60         } else
  61                 // Sleep four seconds before checking for running processes again to avoid having too many workers
  62                 sleep(4);
  63
  64         // Checking number of workers
  65         if (poller_too_much_workers())
  66                 return;
  67
  68         $cooldown = Config::get("system", "worker_cooldown", 0);
  69
  70         $starttime = time();
  71
  72         while ($r = q("SELECT * FROM `workerqueue` WHERE `executed` = '0000-00-00 00:00:00' ORDER BY `priority`, `created` LIMIT 1")) {
  73
  74                 // Constantly check the number of parallel database processes
  75                 if ($a->max_processes_reached())
  76                         return;
  77
  78                 // Constantly check the number of available database connections to let the frontend be accessible at any time
  79                 if (poller_max_connections_reached())
  80                         return;
  81
  82                 // Count active workers and compare them with a maximum value that depends on the load
  83                 if (poller_too_much_workers())
  84                         return;
  85
  86                 q("UPDATE `workerqueue` SET `executed` = '%s', `pid` = %d WHERE `id` = %d AND `executed` = '0000-00-00 00:00:00'",
  87                         dbesc(datetime_convert()),
  88                         intval($mypid),
  89                         intval($r[0]["id"]));
  90
  91                 // Assure that there are no tasks executed twice
  92                 $id = q("SELECT `pid`, `executed` FROM `workerqueue` WHERE `id` = %d", intval($r[0]["id"]));
  93                 if (!$id) {
  94                         logger("Queue item ".$r[0]["id"]." vanished - skip this execution", LOGGER_DEBUG);
  95                         continue;
  96                 } elseif ((strtotime($id[0]["executed"]) <= 0) OR ($id[0]["pid"] == 0)) {
  97                         logger("Entry for queue item ".$r[0]["id"]." wasn't stored - we better stop here", LOGGER_DEBUG);
  98                         return;
  99                 } elseif ($id[0]["pid"] != $mypid) {
 100                         logger("Queue item ".$r[0]["id"]." is to be executed by process ".$id[0]["pid"]." and not by me (".$mypid.") - skip this execution", LOGGER_DEBUG);
 101                         continue;
 102                 }
 103
 104                 $argv = json_decode($r[0]["parameter"]);
 105
 106                 $argc = count($argv);
 107
 108                 // Check for existance and validity of the include file
 109                 $include = $argv[0];
 110
 111                 if (!validate_include($include)) {
 112                         logger("Include file ".$argv[0]." is not valid!");
 113                         q("DELETE FROM `workerqueue` WHERE `id` = %d", intval($r[0]["id"]));
 114                         continue;
 115                 }
 116
 117                 require_once($include);
 118
 119                 $funcname = str_replace(".php", "", basename($argv[0]))."_run";
 120
 121                 if (function_exists($funcname)) {
 122                         logger("Process ".$mypid." - Prio ".$r[0]["priority"]." - ID ".$r[0]["id"].": ".$funcname." ".$r[0]["parameter"]);
 123                         $funcname($argv, $argc);
 124
 125                         if ($cooldown > 0) {
 126                                 logger("Process ".$mypid." - Prio ".$r[0]["priority"]." - ID ".$r[0]["id"].": ".$funcname." - in cooldown for ".$cooldown." seconds");
 127                                 sleep($cooldown);
 128                         }
 129
 130                         logger("Process ".$mypid." - Prio ".$r[0]["priority"]." - ID ".$r[0]["id"].": ".$funcname." - done");
 131
 132                         q("DELETE FROM `workerqueue` WHERE `id` = %d", intval($r[0]["id"]));
 133                 } else
 134                         logger("Function ".$funcname." does not exist");
 135
 136                 // Quit the poller once every hour
 137                 if (time() > ($starttime + 3600))
 138                         return;
 139         }
 140
 141 }
 142
 143 /**
 144  * @brief Checks if the number of database connections has reached a critical limit.
 145  *
 146  * @return bool Are more than 3/4 of the maximum connections used?
 147  */
 148 function poller_max_connections_reached() {
 149
 150         // Fetch the max value from the config. This is needed when the system cannot detect the correct value by itself.
 151         $max = get_config("system", "max_connections");
 152
 153         // Fetch the percentage level where the poller will get active
 154         $maxlevel = get_config("system", "max_connections_level");
 155         if ($maxlevel == 0)
 156                 $maxlevel = 75;
 157
 158         if ($max == 0) {
 159                 // the maximum number of possible user connections can be a system variable
 160                 $r = q("SHOW VARIABLES WHERE `variable_name` = 'max_user_connections'");
 161                 if ($r)
 162                         $max = $r[0]["Value"];
 163
 164                 // Or it can be granted. This overrides the system variable
 165                 $r = q("SHOW GRANTS");
 166                 if ($r)
 167                         foreach ($r AS $grants) {
 168                                 $grant = array_pop($grants);
 169                                 if (stristr($grant, "GRANT USAGE ON"))
 170                                         if (preg_match("/WITH MAX_USER_CONNECTIONS (\d*)/", $grant, $match))
 171                                                 $max = $match[1];
 172                         }
 173         }
 174
 175         // If $max is set we will use the processlist to determine the current number of connections
 176         // The processlist only shows entries of the current user
 177         if ($max != 0) {
 178                 $r = q("SHOW PROCESSLIST");
 179                 if (!$r)
 180                         return false;
 181
 182                 $used = count($r);
 183
 184                 logger("Connection usage (user values): ".$used."/".$max, LOGGER_DEBUG);
 185
 186                 $level = ($used / $max) * 100;
 187
 188                 if ($level >= $maxlevel) {
 189                         logger("Maximum level (".$maxlevel."%) of user connections reached: ".$used."/".$max);
 190                         return true;
 191                 }
 192         }
 193
 194         // We will now check for the system values.
 195         // This limit could be reached although the user limits are fine.
 196         $r = q("SHOW VARIABLES WHERE `variable_name` = 'max_connections'");
 197         if (!$r)
 198                 return false;
 199
 200         $max = intval($r[0]["Value"]);
 201         if ($max == 0)
 202                 return false;
 203
 204         $r = q("SHOW STATUS WHERE `variable_name` = 'Threads_connected'");
 205         if (!$r)
 206                 return false;
 207
 208         $used = intval($r[0]["Value"]);
 209         if ($used == 0)
 210                 return false;
 211
 212         logger("Connection usage (system values): ".$used."/".$max, LOGGER_DEBUG);
 213
 214         $level = $used / $max * 100;
 215
 216         if ($level < $maxlevel)
 217                 return false;
 218
 219         logger("Maximum level (".$level."%) of system connections reached: ".$used."/".$max);
 220         return true;
 221 }
 222
 223 /**
 224  * @brief fix the queue entry if the worker process died
 225  *
 226  */
 227 function poller_kill_stale_workers() {
 228         $r = q("SELECT `pid`, `executed`, `priority`, `parameter` FROM `workerqueue` WHERE `executed` != '0000-00-00 00:00:00'");
 229
 230         if (!dbm::is_result($r)) {
 231                 // No processing here needed
 232                 return;
 233         }
 234
 235         foreach($r AS $pid)
 236                 if (!posix_kill($pid["pid"], 0))
 237                         q("UPDATE `workerqueue` SET `executed` = '0000-00-00 00:00:00', `pid` = 0 WHERE `pid` = %d",
 238                                 intval($pid["pid"]));
 239                 else {
 240                         // Kill long running processes
 241
 242                         // Check if the priority is in a valid range
 243                         if (!in_array($pid["priority"], array(PRIORITY_CRITICAL, PRIORITY_HIGH, PRIORITY_MEDIUM, PRIORITY_LOW, PRIORITY_NEGLIGIBLE)))
 244                                 $pid["priority"] = PRIORITY_MEDIUM;
 245
 246                         // Define the maximum durations
 247                         $max_duration_defaults = array(PRIORITY_CRITICAL => 360, PRIORITY_HIGH => 10, PRIORITY_MEDIUM => 60, PRIORITY_LOW => 180, PRIORITY_NEGLIGIBLE => 360);
 248                         $max_duration = $max_duration_defaults[$pid["priority"]];
 249
 250                         $argv = json_decode($pid["parameter"]);
 251                         $argv[0] = basename($argv[0]);
 252
 253                         // How long is the process already running?
 254                         $duration = (time() - strtotime($pid["executed"])) / 60;
 255                         if ($duration > $max_duration) {
 256                                 logger("Worker process ".$pid["pid"]." (".implode(" ", $argv).") took more than ".$max_duration." minutes. It will be killed now.");
 257                                 posix_kill($pid["pid"], SIGTERM);
 258
 259                                 // We killed the stale process.
 260                                 // To avoid a blocking situation we reschedule the process at the beginning of the queue.
 261                                 // Additionally we are lowering the priority.
 262                                 q("UPDATE `workerqueue` SET `executed` = '0000-00-00 00:00:00', `created` = '%s',
 263                                                         `priority` = %d, `pid` = 0 WHERE `pid` = %d",
 264                                         dbesc(datetime_convert()),
 265                                         intval(PRIORITY_NEGLIGIBLE),
 266                                         intval($pid["pid"]));
 267                         } else
 268                                 logger("Worker process ".$pid["pid"]." (".implode(" ", $argv).") now runs for ".round($duration)." of ".$max_duration." allowed minutes. That's okay.", LOGGER_DEBUG);
 269                 }
 270 }
 271
 272 function poller_too_much_workers() {
 273
 274
 275         $queues = get_config("system", "worker_queues");
 276
 277         if ($queues == 0)
 278                 $queues = 4;
 279
 280         $maxqueues = $queues;
 281
 282         $active = poller_active_workers();
 283
 284         // Decrease the number of workers at higher load
 285         $load = current_load();
 286         if($load) {
 287                 $maxsysload = intval(get_config('system','maxloadavg'));
 288                 if($maxsysload < 1)
 289                         $maxsysload = 50;
 290
 291                 $maxworkers = $queues;
 292
 293                 // Some magical mathemathics to reduce the workers
 294                 $exponent = 3;
 295                 $slope = $maxworkers / pow($maxsysload, $exponent);
 296                 $queues = ceil($slope * pow(max(0, $maxsysload - $load), $exponent));
 297
 298                 $s = q("SELECT COUNT(*) AS `total` FROM `workerqueue` WHERE `executed` = '0000-00-00 00:00:00'");
 299                 $entries = $s[0]["total"];
 300
 301                 if (Config::get("system", "worker_fastlane", false) AND ($queues > 0) AND ($entries > 0) AND ($active >= $queues)) {
 302                         $s = q("SELECT `priority` FROM `workerqueue` WHERE `executed` = '0000-00-00 00:00:00' ORDER BY `priority` LIMIT 1");
 303                         $top_priority = $s[0]["priority"];
 304
 305                         $s = q("SELECT `id` FROM `workerqueue` WHERE `priority` <= %d AND `executed` != '0000-00-00 00:00:00' LIMIT 1",
 306                                 intval($top_priority));
 307                         $high_running = dbm::is_result($s);
 308
 309                         if (!$high_running AND ($top_priority > PRIORITY_UNDEFINED) AND ($top_priority < PRIORITY_NEGLIGIBLE)) {
 310                                 logger("There are jobs with priority ".$top_priority." waiting but none is executed. Open a fastlane.", LOGGER_DEBUG);
 311                                 $queues = $active + 1;
 312                         }
 313                 }
 314
 315                 logger("Current load: ".$load." - maximum: ".$maxsysload." - current queues: ".$active."/".$entries." - maximum: ".$queues."/".$maxqueues, LOGGER_DEBUG);
 316
 317                 // Are there fewer workers running as possible? Then fork a new one.
 318                 if (!get_config("system", "worker_dont_fork") AND ($queues > ($active + 1)) AND ($entries > 1)) {
 319                         logger("Active workers: ".$active."/".$queues." Fork a new worker.", LOGGER_DEBUG);
 320                         $args = array("php", "include/poller.php", "no_cron");
 321                         $a = get_app();
 322                         $a->proc_run($args);
 323                 }
 324         }
 325
 326         return($active >= $queues);
 327 }
 328
 329 function poller_active_workers() {
 330         $workers = q("SELECT COUNT(*) AS `processes` FROM `process` WHERE `command` = 'poller.php'");
 331
 332         return($workers[0]["processes"]);
 333 }
 334
 335 if (array_search(__file__,get_included_files())===0){
 336         poller_run($_SERVER["argv"],$_SERVER["argc"]);
 337
 338         get_app()->end_process();
 339
 340         killme();
 341 }
 342 ?>