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 = q("SELECT * FROM `workerqueue` WHERE `executed` = '0000-00-00 00:00:00' ORDER BY `priority`, `created` LIMIT 1")) {
  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 ($a->max_processes_reached())
  84                         return;
  85
  86                 // Constantly check the number of available database connections to let the frontend be accessible at any time
  87                 if (poller_max_connections_reached())
  88                         return;
  89
  90                 // Count active workers and compare them with a maximum value that depends on the load
  91                 if (poller_too_much_workers())
  92                         return;
  93
  94                 q("UPDATE `workerqueue` SET `executed` = '%s', `pid` = %d WHERE `id` = %d AND `executed` = '0000-00-00 00:00:00'",
  95                         dbesc(datetime_convert()),
  96                         intval($mypid),
  97                         intval($r[0]["id"]));
  98
  99                 // Assure that there are no tasks executed twice
 100                 $id = q("SELECT `pid`, `executed` FROM `workerqueue` WHERE `id` = %d", intval($r[0]["id"]));
 101                 if (!$id) {
 102                         logger("Queue item ".$r[0]["id"]." vanished - skip this execution", LOGGER_DEBUG);
 103                         continue;
 104                 } elseif ((strtotime($id[0]["executed"]) <= 0) OR ($id[0]["pid"] == 0)) {
 105                         logger("Entry for queue item ".$r[0]["id"]." wasn't stored - we better stop here", LOGGER_DEBUG);
 106                         return;
 107                 } elseif ($id[0]["pid"] != $mypid) {
 108                         logger("Queue item ".$r[0]["id"]." is to be executed by process ".$id[0]["pid"]." and not by me (".$mypid.") - skip this execution", LOGGER_DEBUG);
 109                         continue;
 110                 }
 111
 112                 $argv = json_decode($r[0]["parameter"]);
 113
 114                 $argc = count($argv);
 115
 116                 // Check for existance and validity of the include file
 117                 $include = $argv[0];
 118
 119                 if (!validate_include($include)) {
 120                         logger("Include file ".$argv[0]." is not valid!");
 121                         q("DELETE FROM `workerqueue` WHERE `id` = %d", intval($r[0]["id"]));
 122                         continue;
 123                 }
 124
 125                 require_once($include);
 126
 127                 $funcname = str_replace(".php", "", basename($argv[0]))."_run";
 128
 129                 if (function_exists($funcname)) {
 130                         logger("Process ".$mypid." - Prio ".$r[0]["priority"]." - ID ".$r[0]["id"].": ".$funcname." ".$r[0]["parameter"]);
 131                         $funcname($argv, $argc);
 132
 133                         if ($cooldown > 0) {
 134                                 logger("Process ".$mypid." - Prio ".$r[0]["priority"]." - ID ".$r[0]["id"].": ".$funcname." - in cooldown for ".$cooldown." seconds");
 135                                 sleep($cooldown);
 136                         }
 137
 138                         logger("Process ".$mypid." - Prio ".$r[0]["priority"]." - ID ".$r[0]["id"].": ".$funcname." - done");
 139
 140                         q("DELETE FROM `workerqueue` WHERE `id` = %d", intval($r[0]["id"]));
 141                 } else
 142                         logger("Function ".$funcname." does not exist");
 143
 144                 // Quit the poller once every hour
 145                 if (time() > ($starttime + 3600))
 146                         return;
 147         }
 148
 149 }
 150
 151 /**
 152  * @brief Checks if the number of database connections has reached a critical limit.
 153  *
 154  * @return bool Are more than 3/4 of the maximum connections used?
 155  */
 156 function poller_max_connections_reached() {
 157
 158         // Fetch the max value from the config. This is needed when the system cannot detect the correct value by itself.
 159         $max = get_config("system", "max_connections");
 160
 161         // Fetch the percentage level where the poller will get active
 162         $maxlevel = get_config("system", "max_connections_level");
 163         if ($maxlevel == 0)
 164                 $maxlevel = 75;
 165
 166         if ($max == 0) {
 167                 // the maximum number of possible user connections can be a system variable
 168                 $r = q("SHOW VARIABLES WHERE `variable_name` = 'max_user_connections'");
 169                 if ($r)
 170                         $max = $r[0]["Value"];
 171
 172                 // Or it can be granted. This overrides the system variable
 173                 $r = q("SHOW GRANTS");
 174                 if ($r)
 175                         foreach ($r AS $grants) {
 176                                 $grant = array_pop($grants);
 177                                 if (stristr($grant, "GRANT USAGE ON"))
 178                                         if (preg_match("/WITH MAX_USER_CONNECTIONS (\d*)/", $grant, $match))
 179                                                 $max = $match[1];
 180                         }
 181         }
 182
 183         // If $max is set we will use the processlist to determine the current number of connections
 184         // The processlist only shows entries of the current user
 185         if ($max != 0) {
 186                 $r = q("SHOW PROCESSLIST");
 187                 if (!$r)
 188                         return false;
 189
 190                 $used = count($r);
 191
 192                 logger("Connection usage (user values): ".$used."/".$max, LOGGER_DEBUG);
 193
 194                 $level = ($used / $max) * 100;
 195
 196                 if ($level >= $maxlevel) {
 197                         logger("Maximum level (".$maxlevel."%) of user connections reached: ".$used."/".$max);
 198                         return true;
 199                 }
 200         }
 201
 202         // We will now check for the system values.
 203         // This limit could be reached although the user limits are fine.
 204         $r = q("SHOW VARIABLES WHERE `variable_name` = 'max_connections'");
 205         if (!$r)
 206                 return false;
 207
 208         $max = intval($r[0]["Value"]);
 209         if ($max == 0)
 210                 return false;
 211
 212         $r = q("SHOW STATUS WHERE `variable_name` = 'Threads_connected'");
 213         if (!$r)
 214                 return false;
 215
 216         $used = intval($r[0]["Value"]);
 217         if ($used == 0)
 218                 return false;
 219
 220         logger("Connection usage (system values): ".$used."/".$max, LOGGER_DEBUG);
 221
 222         $level = $used / $max * 100;
 223
 224         if ($level < $maxlevel)
 225                 return false;
 226
 227         logger("Maximum level (".$level."%) of system connections reached: ".$used."/".$max);
 228         return true;
 229 }
 230
 231 /**
 232  * @brief fix the queue entry if the worker process died
 233  *
 234  */
 235 function poller_kill_stale_workers() {
 236         $r = q("SELECT `pid`, `executed`, `priority`, `parameter` FROM `workerqueue` WHERE `executed` != '0000-00-00 00:00:00'");
 237
 238         if (!dbm::is_result($r)) {
 239                 // No processing here needed
 240                 return;
 241         }
 242
 243         foreach($r AS $pid)
 244                 if (!posix_kill($pid["pid"], 0))
 245                         q("UPDATE `workerqueue` SET `executed` = '0000-00-00 00:00:00', `pid` = 0 WHERE `pid` = %d",
 246                                 intval($pid["pid"]));
 247                 else {
 248                         // Kill long running processes
 249
 250                         // Check if the priority is in a valid range
 251                         if (!in_array($pid["priority"], array(PRIORITY_CRITICAL, PRIORITY_HIGH, PRIORITY_MEDIUM, PRIORITY_LOW, PRIORITY_NEGLIGIBLE)))
 252                                 $pid["priority"] = PRIORITY_MEDIUM;
 253
 254                         // Define the maximum durations
 255                         $max_duration_defaults = array(PRIORITY_CRITICAL => 360, PRIORITY_HIGH => 10, PRIORITY_MEDIUM => 60, PRIORITY_LOW => 180, PRIORITY_NEGLIGIBLE => 360);
 256                         $max_duration = $max_duration_defaults[$pid["priority"]];
 257
 258                         $argv = json_decode($pid["parameter"]);
 259                         $argv[0] = basename($argv[0]);
 260
 261                         // How long is the process already running?
 262                         $duration = (time() - strtotime($pid["executed"])) / 60;
 263                         if ($duration > $max_duration) {
 264                                 logger("Worker process ".$pid["pid"]." (".implode(" ", $argv).") took more than ".$max_duration." minutes. It will be killed now.");
 265                                 posix_kill($pid["pid"], SIGTERM);
 266
 267                                 // We killed the stale process.
 268                                 // To avoid a blocking situation we reschedule the process at the beginning of the queue.
 269                                 // Additionally we are lowering the priority.
 270                                 q("UPDATE `workerqueue` SET `executed` = '0000-00-00 00:00:00', `created` = '%s',
 271                                                         `priority` = %d, `pid` = 0 WHERE `pid` = %d",
 272                                         dbesc(datetime_convert()),
 273                                         intval(PRIORITY_NEGLIGIBLE),
 274                                         intval($pid["pid"]));
 275                         } else
 276                                 logger("Worker process ".$pid["pid"]." (".implode(" ", $argv).") now runs for ".round($duration)." of ".$max_duration." allowed minutes. That's okay.", LOGGER_DEBUG);
 277                 }
 278 }
 279
 280 function poller_too_much_workers() {
 281
 282
 283         $queues = get_config("system", "worker_queues");
 284
 285         if ($queues == 0)
 286                 $queues = 4;
 287
 288         $maxqueues = $queues;
 289
 290         $active = poller_active_workers();
 291
 292         // Decrease the number of workers at higher load
 293         $load = current_load();
 294         if($load) {
 295                 $maxsysload = intval(get_config('system','maxloadavg'));
 296                 if($maxsysload < 1)
 297                         $maxsysload = 50;
 298
 299                 $maxworkers = $queues;
 300
 301                 // Some magical mathemathics to reduce the workers
 302                 $exponent = 3;
 303                 $slope = $maxworkers / pow($maxsysload, $exponent);
 304                 $queues = ceil($slope * pow(max(0, $maxsysload - $load), $exponent));
 305
 306                 $s = q("SELECT COUNT(*) AS `total` FROM `workerqueue` WHERE `executed` = '0000-00-00 00:00:00'");
 307                 $entries = $s[0]["total"];
 308
 309                 if (Config::get("system", "worker_fastlane", false) AND ($queues > 0) AND ($entries > 0) AND ($active >= $queues)) {
 310                         $s = q("SELECT `priority` FROM `workerqueue` WHERE `executed` = '0000-00-00 00:00:00' ORDER BY `priority` LIMIT 1");
 311                         $top_priority = $s[0]["priority"];
 312
 313                         $s = q("SELECT `id` FROM `workerqueue` WHERE `priority` <= %d AND `executed` != '0000-00-00 00:00:00' LIMIT 1",
 314                                 intval($top_priority));
 315                         $high_running = dbm::is_result($s);
 316
 317                         if (!$high_running AND ($top_priority > PRIORITY_UNDEFINED) AND ($top_priority < PRIORITY_NEGLIGIBLE)) {
 318                                 logger("There are jobs with priority ".$top_priority." waiting but none is executed. Open a fastlane.", LOGGER_DEBUG);
 319                                 $queues = $active + 1;
 320                         }
 321                 }
 322
 323                 logger("Current load: ".$load." - maximum: ".$maxsysload." - current queues: ".$active."/".$entries." - maximum: ".$queues."/".$maxqueues, LOGGER_DEBUG);
 324
 325                 // Are there fewer workers running as possible? Then fork a new one.
 326                 if (!get_config("system", "worker_dont_fork") AND ($queues > ($active + 1)) AND ($entries > 1)) {
 327                         logger("Active workers: ".$active."/".$queues." Fork a new worker.", LOGGER_DEBUG);
 328                         $args = array("php", "include/poller.php", "no_cron");
 329                         $a = get_app();
 330                         $a->proc_run($args);
 331                 }
 332         }
 333
 334         return($active >= $queues);
 335 }
 336
 337 function poller_active_workers() {
 338         $workers = q("SELECT COUNT(*) AS `processes` FROM `process` WHERE `command` = 'poller.php'");
 339
 340         return($workers[0]["processes"]);
 341 }
 342
 343 if (array_search(__file__,get_included_files())===0){
 344         poller_run($_SERVER["argv"],$_SERVER["argc"]);
 345
 346         get_app()->end_process();
 347
 348         killme();
 349 }
 350 ?>