friendica/include/poller.php
2017-06-13 05:52:59 +00:00

776 lines
23 KiB
PHP

<?php
use Friendica\App;
use Friendica\Core\Config;
use Friendica\Util\Lock;
if (!file_exists("boot.php") && (sizeof($_SERVER["argv"]) != 0)) {
$directory = dirname($_SERVER["argv"][0]);
if (substr($directory, 0, 1) != "/") {
$directory = $_SERVER["PWD"]."/".$directory;
}
$directory = realpath($directory."/..");
chdir($directory);
}
require_once("boot.php");
function poller_run($argv, $argc){
global $a, $db;
$a = new App(dirname(__DIR__));
@include(".htconfig.php");
require_once("include/dba.php");
$db = new dba($db_host, $db_user, $db_pass, $db_data);
unset($db_host, $db_user, $db_pass, $db_data);
Config::load();
// Quit when in maintenance
if (Config::get('system', 'maintenance', true)) {
return;
}
$a->set_baseurl(Config::get('system', 'url'));
load_hooks();
// At first check the maximum load. We shouldn't continue with a high load
if ($a->maxload_reached()) {
logger('Pre check: maximum load reached, quitting.', LOGGER_DEBUG);
return;
}
// We now start the process. This is done after the load check since this could increase the load.
$a->start_process();
// Kill stale processes every 5 minutes
$last_cleanup = Config::get('system', 'poller_last_cleaned', 0);
if (time() > ($last_cleanup + 300)) {
Config::set('system', 'poller_last_cleaned', time());
poller_kill_stale_workers();
}
// Count active workers and compare them with a maximum value that depends on the load
if (poller_too_much_workers()) {
logger('Pre check: Active worker limit reached, quitting.', LOGGER_DEBUG);
return;
}
// Do we have too few memory?
if ($a->min_memory_reached()) {
logger('Pre check: Memory limit reached, quitting.', LOGGER_DEBUG);
return;
}
// Possibly there are too much database connections
if (poller_max_connections_reached()) {
logger('Pre check: maximum connections reached, quitting.', LOGGER_DEBUG);
return;
}
// Possibly there are too much database processes that block the system
if ($a->max_processes_reached()) {
logger('Pre check: maximum processes reached, quitting.', LOGGER_DEBUG);
return;
}
// Now we start additional cron processes if we should do so
if (($argc <= 1) || ($argv[1] != "no_cron")) {
poller_run_cron();
}
$starttime = time();
// We fetch the next queue entry that is about to be executed
while ($r = poller_worker_process()) {
foreach ($r AS $entry) {
// Assure that the priority is an integer value
$entry['priority'] = (int)$entry['priority'];
// The work will be done
if (!poller_execute($entry)) {
logger('Process execution failed, quitting.', LOGGER_DEBUG);
return;
}
// To avoid the quitting of multiple pollers only one poller at a time will execute the check
if (Lock::set('poller_worker', 0)) {
// Count active workers and compare them with a maximum value that depends on the load
if (poller_too_much_workers()) {
logger('Active worker limit reached, quitting.', LOGGER_DEBUG);
return;
}
// Check free memory
if ($a->min_memory_reached()) {
logger('Memory limit reached, quitting.', LOGGER_DEBUG);
return;
}
Lock::remove('poller_worker');
}
}
// Quit the poller once every hour
if (time() > ($starttime + 3600)) {
logger('Process lifetime reached, quitting.', LOGGER_DEBUG);
return;
}
}
logger("Couldn't select a workerqueue entry, quitting.", LOGGER_DEBUG);
}
/**
* @brief Returns the number of non executed entries in the worker queue
*
* @return integer Number of non executed entries in the worker queue
*/
function poller_total_entries() {
$s = q("SELECT COUNT(*) AS `total` FROM `workerqueue` WHERE `executed` <= '%s'", dbesc(NULL_DATE));
return $s[0]["total"];
}
/**
* @brief Returns the highest priority in the worker queue that isn't executed
*
* @return integer Number of active poller processes
*/
function poller_highest_priority() {
$s = q("SELECT `priority` FROM `workerqueue` WHERE `executed` <= '%s' ORDER BY `priority` LIMIT 1", dbesc(NULL_DATE));
return $s[0]["priority"];
}
/**
* @brief Returns if a process with the given priority is running
*
* @param integer $priority The priority that should be checked
*
* @return integer Is there a process running with that priority?
*/
function poller_process_with_priority_active($priority) {
$s = q("SELECT `id` FROM `workerqueue` WHERE `priority` <= %d AND `executed` > '%s' LIMIT 1",
intval($priority), dbesc(NULL_DATE));
return dbm::is_result($s);
}
/**
* @brief Execute a worker entry
*
* @param array $queue Workerqueue entry
*
* @return boolean "true" if further processing should be stopped
*/
function poller_execute($queue) {
$a = get_app();
$mypid = getmypid();
// Quit when in maintenance
if (Config::get('system', 'maintenance', true)) {
logger("Maintenance mode - quit process ".$mypid, LOGGER_DEBUG);
return false;
}
// Constantly check the number of parallel database processes
if ($a->max_processes_reached()) {
logger("Max processes reached for process ".$mypid, LOGGER_DEBUG);
return false;
}
// Constantly check the number of available database connections to let the frontend be accessible at any time
if (poller_max_connections_reached()) {
logger("Max connection reached for process ".$mypid, LOGGER_DEBUG);
return false;
}
$argv = json_decode($queue["parameter"]);
// Check for existance and validity of the include file
$include = $argv[0];
if (!validate_include($include)) {
logger("Include file ".$argv[0]." is not valid!");
dba::delete('workerqueue', array('id' => $queue["id"]));
return true;
}
require_once($include);
$funcname = str_replace(".php", "", basename($argv[0]))."_run";
if (function_exists($funcname)) {
poller_exec_function($queue, $funcname, $argv);
dba::delete('workerqueue', array('id' => $queue["id"]));
} else {
logger("Function ".$funcname." does not exist");
}
return true;
}
/**
* @brief Execute a function from the queue
*
* @param array $queue Workerqueue entry
* @param string $funcname name of the function
* @param array $argv Array of values to be passed to the function
*/
function poller_exec_function($queue, $funcname, $argv) {
$a = get_app();
$mypid = getmypid();
$argc = count($argv);
logger("Process ".$mypid." - Prio ".$queue["priority"]." - ID ".$queue["id"].": ".$funcname." ".$queue["parameter"]);
$stamp = (float)microtime(true);
// We use the callstack here to analyze the performance of executed worker entries.
// For this reason the variables have to be initialized.
if (Config::get("system", "profiler")) {
$a->performance["start"] = microtime(true);
$a->performance["database"] = 0;
$a->performance["database_write"] = 0;
$a->performance["network"] = 0;
$a->performance["file"] = 0;
$a->performance["rendering"] = 0;
$a->performance["parser"] = 0;
$a->performance["marktime"] = 0;
$a->performance["markstart"] = microtime(true);
$a->callstack = array();
}
// For better logging create a new process id for every worker call
// But preserve the old one for the worker
$old_process_id = $a->process_id;
$a->process_id = uniqid("wrk", true);
$a->queue = $queue;
$funcname($argv, $argc);
$a->process_id = $old_process_id;
unset($a->queue);
$duration = number_format(microtime(true) - $stamp, 3);
if ($duration > 3600) {
logger("Prio ".$queue["priority"].": ".$queue["parameter"]." - longer than 1 hour (".round($duration/60, 3).")", LOGGER_DEBUG);
} elseif ($duration > 600) {
logger("Prio ".$queue["priority"].": ".$queue["parameter"]." - longer than 10 minutes (".round($duration/60, 3).")", LOGGER_DEBUG);
} elseif ($duration > 300) {
logger("Prio ".$queue["priority"].": ".$queue["parameter"]." - longer than 5 minutes (".round($duration/60, 3).")", LOGGER_DEBUG);
} elseif ($duration > 120) {
logger("Prio ".$queue["priority"].": ".$queue["parameter"]." - longer than 2 minutes (".round($duration/60, 3).")", LOGGER_DEBUG);
}
logger("Process ".$mypid." - Prio ".$queue["priority"]." - ID ".$queue["id"].": ".$funcname." - done in ".$duration." seconds.");
// Write down the performance values into the log
if (Config::get("system", "profiler")) {
$duration = microtime(true)-$a->performance["start"];
if (Config::get("rendertime", "callstack")) {
if (isset($a->callstack["database"])) {
$o = "\nDatabase Read:\n";
foreach ($a->callstack["database"] AS $func => $time) {
$time = round($time, 3);
if ($time > 0) {
$o .= $func.": ".$time."\n";
}
}
}
if (isset($a->callstack["database_write"])) {
$o .= "\nDatabase Write:\n";
foreach ($a->callstack["database_write"] AS $func => $time) {
$time = round($time, 3);
if ($time > 0) {
$o .= $func.": ".$time."\n";
}
}
}
if (isset($a->callstack["network"])) {
$o .= "\nNetwork:\n";
foreach ($a->callstack["network"] AS $func => $time) {
$time = round($time, 3);
if ($time > 0) {
$o .= $func.": ".$time."\n";
}
}
}
} else {
$o = '';
}
logger("ID ".$queue["id"].": ".$funcname.": ".sprintf("DB: %s/%s, Net: %s, I/O: %s, Other: %s, Total: %s".$o,
number_format($a->performance["database"] - $a->performance["database_write"], 2),
number_format($a->performance["database_write"], 2),
number_format($a->performance["network"], 2),
number_format($a->performance["file"], 2),
number_format($duration - ($a->performance["database"] + $a->performance["network"] + $a->performance["file"]), 2),
number_format($duration, 2)),
LOGGER_DEBUG);
}
$cooldown = Config::get("system", "worker_cooldown", 0);
if ($cooldown > 0) {
logger("Process ".$mypid." - Prio ".$queue["priority"]." - ID ".$queue["id"].": ".$funcname." - in cooldown for ".$cooldown." seconds");
sleep($cooldown);
}
}
/**
* @brief Checks if the number of database connections has reached a critical limit.
*
* @return bool Are more than 3/4 of the maximum connections used?
*/
function poller_max_connections_reached() {
// Fetch the max value from the config. This is needed when the system cannot detect the correct value by itself.
$max = Config::get("system", "max_connections");
// Fetch the percentage level where the poller will get active
$maxlevel = Config::get("system", "max_connections_level", 75);
if ($max == 0) {
// the maximum number of possible user connections can be a system variable
$r = q("SHOW VARIABLES WHERE `variable_name` = 'max_user_connections'");
if (dbm::is_result($r)) {
$max = $r[0]["Value"];
}
// Or it can be granted. This overrides the system variable
$r = q("SHOW GRANTS");
if (dbm::is_result($r)) {
foreach ($r AS $grants) {
$grant = array_pop($grants);
if (stristr($grant, "GRANT USAGE ON")) {
if (preg_match("/WITH MAX_USER_CONNECTIONS (\d*)/", $grant, $match)) {
$max = $match[1];
}
}
}
}
}
// If $max is set we will use the processlist to determine the current number of connections
// The processlist only shows entries of the current user
if ($max != 0) {
$r = q("SHOW PROCESSLIST");
if (!dbm::is_result($r)) {
return false;
}
$used = count($r);
logger("Connection usage (user values): ".$used."/".$max, LOGGER_DEBUG);
$level = ($used / $max) * 100;
if ($level >= $maxlevel) {
logger("Maximum level (".$maxlevel."%) of user connections reached: ".$used."/".$max);
return true;
}
}
// We will now check for the system values.
// This limit could be reached although the user limits are fine.
$r = q("SHOW VARIABLES WHERE `variable_name` = 'max_connections'");
if (!dbm::is_result($r)) {
return false;
}
$max = intval($r[0]["Value"]);
if ($max == 0) {
return false;
}
$r = q("SHOW STATUS WHERE `variable_name` = 'Threads_connected'");
if (!dbm::is_result($r)) {
return false;
}
$used = intval($r[0]["Value"]);
if ($used == 0) {
return false;
}
logger("Connection usage (system values): ".$used."/".$max, LOGGER_DEBUG);
$level = $used / $max * 100;
if ($level < $maxlevel) {
return false;
}
logger("Maximum level (".$level."%) of system connections reached: ".$used."/".$max);
return true;
}
/**
* @brief fix the queue entry if the worker process died
*
*/
function poller_kill_stale_workers() {
$r = q("SELECT `pid`, `executed`, `priority`, `parameter` FROM `workerqueue` WHERE `executed` > '%s'", dbesc(NULL_DATE));
if (!dbm::is_result($r)) {
// No processing here needed
return;
}
foreach ($r AS $pid) {
if (!posix_kill($pid["pid"], 0)) {
dba::update('workerqueue', array('executed' => NULL_DATE, 'pid' => 0),
array('pid' => $pid["pid"]));
} else {
// Kill long running processes
// Check if the priority is in a valid range
if (!in_array($pid["priority"], array(PRIORITY_CRITICAL, PRIORITY_HIGH, PRIORITY_MEDIUM, PRIORITY_LOW, PRIORITY_NEGLIGIBLE))) {
$pid["priority"] = PRIORITY_MEDIUM;
}
// Define the maximum durations
$max_duration_defaults = array(PRIORITY_CRITICAL => 360, PRIORITY_HIGH => 10, PRIORITY_MEDIUM => 60, PRIORITY_LOW => 180, PRIORITY_NEGLIGIBLE => 360);
$max_duration = $max_duration_defaults[$pid["priority"]];
$argv = json_decode($pid["parameter"]);
$argv[0] = basename($argv[0]);
// How long is the process already running?
$duration = (time() - strtotime($pid["executed"])) / 60;
if ($duration > $max_duration) {
logger("Worker process ".$pid["pid"]." (".implode(" ", $argv).") took more than ".$max_duration." minutes. It will be killed now.");
posix_kill($pid["pid"], SIGTERM);
// We killed the stale process.
// To avoid a blocking situation we reschedule the process at the beginning of the queue.
// Additionally we are lowering the priority.
dba::update('workerqueue',
array('executed' => NULL_DATE, 'created' => datetime_convert(), 'priority' => PRIORITY_NEGLIGIBLE, 'pid' => 0),
array('pid' => $pid["pid"]));
} else {
logger("Worker process ".$pid["pid"]." (".implode(" ", $argv).") now runs for ".round($duration)." of ".$max_duration." allowed minutes. That's okay.", LOGGER_DEBUG);
}
}
}
}
/**
* @brief Checks if the number of active workers exceeds the given limits
*
* @param integer $entries The number of not executed entries in the worker queue
* @param integer $top_priority The highest not executed priority in the worker queue
* @param boolean $high_running Is a process with priority "$top_priority" running?
*
* @return bool Are there too much workers running?
*/
function poller_too_much_workers() {
$queues = Config::get("system", "worker_queues", 4);
$maxqueues = $queues;
$active = poller_active_workers();
// Decrease the number of workers at higher load
$load = current_load();
if ($load) {
$maxsysload = intval(Config::get("system", "maxloadavg", 50));
$maxworkers = $queues;
// Some magical mathemathics to reduce the workers
$exponent = 3;
$slope = $maxworkers / pow($maxsysload, $exponent);
$queues = ceil($slope * pow(max(0, $maxsysload - $load), $exponent));
if (Config::get('system', 'worker_debug')) {
// Create a list of queue entries grouped by their priority
$listitem = array();
// Adding all processes with no workerqueue entry
$processes = dba::p("SELECT COUNT(*) AS `running` FROM `process` WHERE NOT EXISTS (SELECT id FROM `workerqueue` WHERE `workerqueue`.`pid` = `process`.`pid`)");
if ($process = dba::fetch($processes)) {
$listitem[0] = "0:".$process["running"];
}
dba::close($processes);
// Now adding all processes with workerqueue entries
$entries = dba::p("SELECT COUNT(*) AS `entries`, `priority` FROM `workerqueue` GROUP BY `priority`");
while ($entry = dba::fetch($entries)) {
$processes = dba::p("SELECT COUNT(*) AS `running` FROM `process` INNER JOIN `workerqueue` ON `workerqueue`.`pid` = `process`.`pid` WHERE `priority` = ?", $entry["priority"]);
if ($process = dba::fetch($processes)) {
$listitem[$entry["priority"]] = $entry["priority"].":".$process["running"]."/".$entry["entries"];
}
dba::close($processes);
}
dba::close($entries);
$processlist = ' ('.implode(', ', $listitem).')';
}
$entries = poller_total_entries();
if (Config::get("system", "worker_fastlane", false) && ($queues > 0) && ($entries > 0) && ($active >= $queues)) {
$top_priority = poller_highest_priority();
$high_running = poller_process_with_priority_active($top_priority);
if (!$high_running && ($top_priority > PRIORITY_UNDEFINED) && ($top_priority < PRIORITY_NEGLIGIBLE)) {
logger("There are jobs with priority ".$top_priority." waiting but none is executed. Open a fastlane.", LOGGER_DEBUG);
$queues = $active + 1;
}
}
logger("Load: ".$load."/".$maxsysload." - processes: ".$active."/".$entries.$processlist." - maximum: ".$queues."/".$maxqueues, LOGGER_DEBUG);
// Are there fewer workers running as possible? Then fork a new one.
if (!Config::get("system", "worker_dont_fork") && ($queues > ($active + 1)) && ($entries > 1)) {
logger("Active workers: ".$active."/".$queues." Fork a new worker.", LOGGER_DEBUG);
$args = array("include/poller.php", "no_cron");
$a = get_app();
$a->proc_run($args);
}
}
return $active >= $queues;
}
/**
* @brief Returns the number of active poller processes
*
* @return integer Number of active poller processes
*/
function poller_active_workers() {
$workers = q("SELECT COUNT(*) AS `processes` FROM `process` WHERE `command` = 'poller.php'");
return $workers[0]["processes"];
}
/**
* @brief Check if we should pass some slow processes
*
* When the active processes of the highest priority are using more than 2/3
* of all processes, we let pass slower processes.
*
* @param string $highest_priority Returns the currently highest priority
* @return bool We let pass a slower process than $highest_priority
*/
function poller_passing_slow(&$highest_priority) {
$highest_priority = 0;
$r = q("SELECT `priority`
FROM `process`
INNER JOIN `workerqueue` ON `workerqueue`.`pid` = `process`.`pid`");
// No active processes at all? Fine
if (!dbm::is_result($r)) {
return false;
}
$priorities = array();
foreach ($r AS $line) {
$priorities[] = $line["priority"];
}
// Should not happen
if (count($priorities) == 0) {
return false;
}
$highest_priority = min($priorities);
// The highest process is already the slowest one?
// Then we quit
if ($highest_priority == PRIORITY_NEGLIGIBLE) {
return false;
}
$high = 0;
foreach ($priorities AS $priority) {
if ($priority == $highest_priority) {
++$high;
}
}
logger("Highest priority: ".$highest_priority." Total processes: ".count($priorities)." Count high priority processes: ".$high, LOGGER_DEBUG);
$passing_slow = (($high/count($priorities)) > (2/3));
if ($passing_slow) {
logger("Passing slower processes than priority ".$highest_priority, LOGGER_DEBUG);
}
return $passing_slow;
}
/**
* @brief Find and claim the next worker process for us
*
* @return boolean Have we found something?
*/
function find_worker_processes() {
// Check if we should pass some low priority process
$highest_priority = 0;
$found = false;
if (poller_passing_slow($highest_priority)) {
// Are there waiting processes with a higher priority than the currently highest?
$result = dba::p("UPDATE `workerqueue` SET `executed` = ?, `pid` = ?
WHERE `executed` <= ? AND `priority` < ?
ORDER BY `priority`, `created` LIMIT 1",
datetime_convert(), getmypid(), NULL_DATE, $highest_priority);
if (dbm::is_result($result)) {
$found = (dba::num_rows($result) > 0);
}
dba::close($result);
if (!$found) {
// Give slower processes some processing time
$result = dba::p("UPDATE `workerqueue` SET `executed` = ?, `pid` = ?
WHERE `executed` <= ? AND `priority` > ?
ORDER BY `priority`, `created` LIMIT 1",
datetime_convert(), getmypid(), NULL_DATE, $highest_priority);
if (dbm::is_result($result)) {
$found = (dba::num_rows($result) > 0);
}
dba::close($result);
}
}
// If there is no result (or we shouldn't pass lower processes) we check without priority limit
if (!$found) {
$result = dba::p("UPDATE `workerqueue` SET `executed` = ?, `pid` = ? WHERE `executed` <= ? ORDER BY `priority`, `created` LIMIT 1",
datetime_convert(), getmypid(), NULL_DATE);
if (dbm::is_result($result)) {
$found = (dba::num_rows($result) > 0);
}
dba::close($result);
}
return $found;
}
/**
* @brief Returns the next worker process
*
* @return string SQL statement
*/
function poller_worker_process() {
$timeout = 10;
do {
$found = find_worker_processes();
} while (!$found && (poller_total_entries() > 0) && (--$timeout > 0));
if ($found) {
$r = q("SELECT * FROM `workerqueue` WHERE `pid` = %d", intval(getmypid()));
}
return $r;
}
/**
* @brief Removes a workerqueue entry from the current process
*/
function poller_unclaim_process() {
$mypid = getmypid();
dba::update('workerqueue', array('executed' => NULL_DATE, 'pid' => 0), array('pid' => $mypid));
}
/**
* @brief Call the front end worker
*/
function call_worker() {
if (!Config::get("system", "frontend_worker")) {
return;
}
$url = App::get_baseurl()."/worker";
fetch_url($url, false, $redirects, 1);
}
/**
* @brief Call the front end worker if there aren't any active
*/
function call_worker_if_idle() {
if (!Config::get("system", "frontend_worker")) {
return;
}
// Do we have "proc_open"? Then we can fork the poller
if (function_exists("proc_open")) {
// When was the last time that we called the worker?
// Less than one minute? Then we quit
if ((time() - Config::get("system", "worker_started")) < 60) {
return;
}
set_config("system", "worker_started", time());
// Do we have enough running workers? Then we quit here.
if (poller_too_much_workers()) {
// Cleaning dead processes
poller_kill_stale_workers();
get_app()->remove_inactive_processes();
return;
}
poller_run_cron();
logger('Call poller', LOGGER_DEBUG);
$args = array("include/poller.php", "no_cron");
$a = get_app();
$a->proc_run($args);
return;
}
// We cannot execute background processes.
// We now run the processes from the frontend.
// This won't work with long running processes.
poller_run_cron();
clear_worker_processes();
$workers = q("SELECT COUNT(*) AS `processes` FROM `process` WHERE `command` = 'worker.php'");
if ($workers[0]["processes"] == 0) {
call_worker();
}
}
/**
* @brief Removes long running worker processes
*/
function clear_worker_processes() {
$timeout = Config::get("system", "frontend_worker_timeout", 10);
/// @todo We should clean up the corresponding workerqueue entries as well
q("DELETE FROM `process` WHERE `created` < '%s' AND `command` = 'worker.php'",
dbesc(datetime_convert('UTC','UTC',"now - ".$timeout." minutes")));
}
/**
* @brief Runs the cron processes
*/
function poller_run_cron() {
logger('Add cron entries', LOGGER_DEBUG);
// Check for spooled items
proc_run(PRIORITY_HIGH, "include/spool_post.php");
// Run the cron job that calls all other jobs
proc_run(PRIORITY_MEDIUM, "include/cron.php");
// Run the cronhooks job separately from cron for being able to use a different timing
proc_run(PRIORITY_MEDIUM, "include/cronhooks.php");
// Cleaning dead processes
poller_kill_stale_workers();
}
if (array_search(__file__,get_included_files())===0){
poller_run($_SERVER["argv"],$_SERVER["argc"]);
poller_unclaim_process();
get_app()->end_process();
Lock::remove('poller_worker');
killme();
}