Merge pull request #6719 from annando/worker-scheduler

New scheduler mechanism - now to the correct branch
This commit is contained in:
Hypolite Petovan 2019-02-21 16:12:19 -05:00 committed by GitHub
commit 4375edd63e
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4 changed files with 187 additions and 240 deletions

View file

@ -34,7 +34,7 @@
use Friendica\Database\DBA;
if (!defined('DB_UPDATE_VERSION')) {
define('DB_UPDATE_VERSION', 1302);
define('DB_UPDATE_VERSION', 1303);
}
return [
@ -1378,9 +1378,8 @@ return [
"PRIMARY" => ["id"],
"done_parameter" => ["done", "parameter(64)"],
"done_executed" => ["done", "executed"],
"done_priority" => ["done", "priority"],
"done_priority_created" => ["done", "priority", "created"],
"done_pid" => ["done", "pid"],
"done_priority_next_try" => ["done", "priority", "next_try"],
"done_pid_next_try" => ["done", "pid", "next_try"],
"done_pid_priority_created" => ["done", "pid", "priority", "created"]
]

View file

@ -41,11 +41,7 @@ function worker_init()
Worker::callWorker();
$passing_slow = false;
$entries = 0;
$deferred = 0;
if ($r = Worker::workerProcess($passing_slow, $entries, $deferred)) {
if ($r = Worker::workerProcess()) {
// On most configurations this parameter wouldn't have any effect.
// But since it doesn't destroy anything, we just try to get more execution time in any way.
set_time_limit(0);

View file

@ -92,15 +92,8 @@ class Worker
$starttime = time();
$entries = 0;
$deferred = 0;
// We fetch the next queue entry that is about to be executed
while ($r = self::workerProcess($passing_slow, $entries, $deferred)) {
// When we are processing jobs with a lower priority, we don't refetch new jobs
// Otherwise fast jobs could wait behind slow ones and could be blocked.
$refetched = $passing_slow;
while ($r = self::workerProcess()) {
foreach ($r as $entry) {
// Assure that the priority is an integer value
$entry['priority'] = (int)$entry['priority'];
@ -112,20 +105,16 @@ class Worker
}
// If possible we will fetch new jobs for this worker
if (!$refetched) {
$entries = self::totalEntries();
$deferred = self::deferredEntries();
if (Lock::acquire('worker_process', 0)) {
$refetched = self::findWorkerProcesses($passing_slow, $entries, $deferred);
if (!self::getWaitingJobForPID() && Lock::acquire('worker_process', 0)) {
self::findWorkerProcesses();
Lock::release('worker_process');
}
}
}
// To avoid the quitting of multiple workers only one worker at a time will execute the check
if (Lock::acquire('worker', 0)) {
// Count active workers and compare them with a maximum value that depends on the load
if (self::tooMuchWorkers($entries, $deferred)) {
if (self::tooMuchWorkers()) {
Logger::log('Active worker limit reached, quitting.', Logger::DEBUG);
Lock::release('worker');
return;
@ -409,16 +398,15 @@ class Worker
* The execution time is the productive time.
* By changing parameters like the maximum number of workers we can check the effectivness.
*/
Logger::log(
'DB: '.number_format(self::$db_duration - (self::$db_duration_count + self::$db_duration_write + self::$db_duration_stat), 4).
' - DB-Count: '.number_format(self::$db_duration_count, 4).
' - DB-Stat: '.number_format(self::$db_duration_stat, 4).
' - DB-Write: '.number_format(self::$db_duration_write, 4).
' - Lock: '.number_format(self::$lock_duration, 4).
' - Rest: '.number_format(max(0, $up_duration - (self::$db_duration + self::$lock_duration)), 4).
' - Execution: '.number_format($duration, 4),
Logger::DEBUG
);
$dbtotal = number_format(self::$db_duration - (self::$db_duration_count + self::$db_duration_write + self::$db_duration_stat), 4);
$dbcount = number_format(self::$db_duration_count, 4);
$dbstat = number_format(self::$db_duration_stat, 4);
$dbwrite = number_format(self::$db_duration_write, 4);
$dblock = number_format(self::$lock_duration, 4);
$rest = number_format(max(0, $up_duration - (self::$db_duration + self::$lock_duration)), 4);
$exec = number_format($duration, 4);
Logger::info('Performance:', ['total' => $dbtotal, 'count' => $dbcount, 'stat' => $dbstat, 'write' => $dbwrite, 'block' => $dblock, 'rest' => $rest, 'exec' => $exec]);
self::$up_start = microtime(true);
self::$db_duration = 0;
@ -607,13 +595,10 @@ class Worker
/**
* @brief Checks if the number of active workers exceeds the given limits
*
* @param integer $entries Total number of queue entries
* @param integer $deferred Number of deferred queue entries
*
* @return bool Are there too much workers running?
* @throws \Friendica\Network\HTTPException\InternalServerErrorException
*/
public static function tooMuchWorkers($entries = 0, $deferred = 0)
private static function tooMuchWorkers()
{
$queues = Config::get("system", "worker_queues", 4);
@ -664,12 +649,7 @@ class Worker
$idle_workers = $active;
if (empty($deferred) && empty($entries)) {
$deferred = self::deferredEntries();
$entries = max(self::totalEntries() - $deferred, 0);
}
$waiting_processes = max(0, $entries - $deferred);
if (Config::get('system', 'worker_debug')) {
$waiting_processes = 0;
@ -691,10 +671,14 @@ class Worker
DBA::close($processes);
}
DBA::close($jobs);
$entries = $deferred + $waiting_processes;
} else {
$entries = self::totalEntries();
$waiting_processes = max(0, $entries - $deferred);
$stamp = (float)microtime(true);
$jobs = DBA::p("SELECT COUNT(*) AS `running`, `priority` FROM `process` INNER JOIN `workerqueue` ON `workerqueue`.`pid` = `process`.`pid` AND NOT `done` GROUP BY `priority` ORDER BY `priority`");
self::$db_duration += (microtime(true) - $stamp);
self::$db_duration_stat += (microtime(true) - $stamp);
while ($entry = DBA::fetch($jobs)) {
$idle_workers -= $entry["running"];
@ -753,201 +737,13 @@ class Worker
}
/**
* @brief Check if we should pass some slow processes
* @brief Returns waiting jobs for the current process id
*
* 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 $highest_priority
* @return array waiting workerqueue jobs
* @throws \Exception
*/
private static function passingSlow(&$highest_priority)
private static function getWaitingJobForPID()
{
$highest_priority = 0;
$stamp = (float)microtime(true);
$r = DBA::p(
"SELECT `priority`
FROM `process`
INNER JOIN `workerqueue` ON `workerqueue`.`pid` = `process`.`pid` AND NOT `done`"
);
self::$db_duration += (microtime(true) - $stamp);
// No active processes at all? Fine
if (!DBA::isResult($r)) {
return false;
}
$priorities = [];
while ($line = DBA::fetch($r)) {
$priorities[] = $line["priority"];
}
DBA::close($r);
// 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::log("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::log("Passing slower processes than priority ".$highest_priority, Logger::DEBUG);
}
return $passing_slow;
}
/**
* @brief Find and claim the next worker process for us
*
* @param boolean $passing_slow Returns if we had passed low priority processes
* @param integer $entries Total number of queue entries
* @param integer $deferred Number of deferred queue entries
* @return boolean Have we found something?
* @throws \Friendica\Network\HTTPException\InternalServerErrorException
*/
private static function findWorkerProcesses(&$passing_slow, $entries, $deferred)
{
$mypid = getmypid();
// Check if we should pass some low priority process
$highest_priority = 0;
$found = false;
$passing_slow = false;
// The higher the number of parallel workers, the more we prefetch to prevent concurring access
// We decrease the limit with the number of entries left in the queue
$worker_queues = Config::get("system", "worker_queues", 4);
$queue_length = Config::get('system', 'worker_fetch_limit', 1);
$lower_job_limit = $worker_queues * $queue_length * 2;
$entries = max($entries - $deferred, 0);
// Now do some magic
$exponent = 2;
$slope = $queue_length / pow($lower_job_limit, $exponent);
$limit = min($queue_length, ceil($slope * pow($entries, $exponent)));
Logger::log('Deferred: ' . $deferred . ' - Total: ' . $entries . ' - Maximum: ' . $queue_length . ' - jobs per queue: ' . $limit, Logger::DEBUG);
$ids = [];
if (self::passingSlow($highest_priority)) {
// Are there waiting processes with a higher priority than the currently highest?
$stamp = (float)microtime(true);
$result = DBA::select(
'workerqueue',
['id'],
["`pid` = 0 AND `priority` < ? AND NOT `done` AND `next_try` < ?",
$highest_priority, DateTimeFormat::utcNow()],
['limit' => 1, 'order' => ['priority', 'created']]
);
self::$db_duration += (microtime(true) - $stamp);
while ($id = DBA::fetch($result)) {
$ids[] = $id["id"];
}
DBA::close($result);
$found = (count($ids) > 0);
if (!$found) {
// Give slower processes some processing time
$stamp = (float)microtime(true);
$result = DBA::select(
'workerqueue',
['id'],
["`pid` = 0 AND `priority` > ? AND NOT `done` AND `next_try` < ?",
$highest_priority, DateTimeFormat::utcNow()],
['limit' => 1, 'order' => ['priority', 'created']]
);
self::$db_duration += (microtime(true) - $stamp);
while ($id = DBA::fetch($result)) {
$ids[] = $id["id"];
}
DBA::close($result);
$found = (count($ids) > 0);
$passing_slow = $found;
}
}
// At first try to fetch a bunch of high or medium tasks
if (!$found && ($limit > 1)) {
$stamp = (float)microtime(true);
$result = DBA::select(
'workerqueue',
['id'],
["`pid` = 0 AND NOT `done` AND `priority` <= ? AND `next_try` < ? AND `retrial` = 0",
PRIORITY_MEDIUM, DateTimeFormat::utcNow()],
['limit' => $limit, 'order' => ['created']]
);
self::$db_duration += (microtime(true) - $stamp);
while ($id = DBA::fetch($result)) {
$ids[] = $id["id"];
}
DBA::close($result);
$found = (count($ids) > 0);
}
// If there is no result (or we shouldn't pass lower processes) we check without priority limit
if (!$found) {
$stamp = (float)microtime(true);
$result = DBA::select(
'workerqueue',
['id'],
["`pid` = 0 AND NOT `done` AND `next_try` < ?",
DateTimeFormat::utcNow()],
['limit' => 1, 'order' => ['priority', 'created']]
);
self::$db_duration += (microtime(true) - $stamp);
while ($id = DBA::fetch($result)) {
$ids[] = $id["id"];
}
DBA::close($result);
$found = (count($ids) > 0);
}
if ($found) {
$stamp = (float)microtime(true);
$condition = "`id` IN (".substr(str_repeat("?, ", count($ids)), 0, -2).") AND `pid` = 0 AND NOT `done`";
array_unshift($ids, $condition);
DBA::update('workerqueue', ['executed' => DateTimeFormat::utcNow(), 'pid' => $mypid], $ids);
self::$db_duration += (microtime(true) - $stamp);
self::$db_duration_write += (microtime(true) - $stamp);
}
return $found;
}
/**
* @brief Returns the next worker process
*
* @param boolean $passing_slow Returns if we had passed low priority processes
* @param integer $entries Returns total number of queue entries
* @param integer $deferred Returns number of deferred queue entries
*
* @return string SQL statement
* @throws \Friendica\Network\HTTPException\InternalServerErrorException
*/
public static function workerProcess(&$passing_slow, &$entries, &$deferred)
{
// There can already be jobs for us in the queue.
$stamp = (float)microtime(true);
$r = DBA::select('workerqueue', [], ['pid' => getmypid(), 'done' => false]);
self::$db_duration += (microtime(true) - $stamp);
@ -956,9 +752,165 @@ class Worker
}
DBA::close($r);
// Counting the rows outside the lock reduces the lock time
$entries = self::totalEntries();
$deferred = self::deferredEntries();
return false;
}
/**
* @brief Returns the next jobs that should be executed
*
* @return array array with next jobs
* @throws \Exception
*/
private static function nextProcess()
{
$priority = self::nextPriority();
if (empty($priority)) {
Logger::info('No tasks found');
return [];
}
if ($priority <= PRIORITY_MEDIUM) {
$limit = Config::get('system', 'worker_fetch_limit', 1);
} else {
$limit = 1;
}
$ids = [];
$stamp = (float)microtime(true);
$condition = ["`priority` = ? AND `pid` = 0 AND NOT `done` AND `next_try` < ?", $priority, DateTimeFormat::utcNow()];
$tasks = DBA::select('workerqueue', ['id'], $condition, ['limit' => $limit, 'order' => ['created']]);
self::$db_duration += (microtime(true) - $stamp);
while ($task = DBA::fetch($tasks)) {
$ids[] = $task['id'];
}
DBA::close($tasks);
Logger::info('Found:', ['id' => $ids, 'priority' => $priority]);
return $ids;
}
/**
* @brief Returns the priority of the next workerqueue job
*
* @return string priority
* @throws \Exception
*/
private static function nextPriority()
{
$waiting = [];
$priorities = [PRIORITY_CRITICAL, PRIORITY_HIGH, PRIORITY_MEDIUM, PRIORITY_LOW, PRIORITY_NEGLIGIBLE];
foreach ($priorities as $priority) {
$stamp = (float)microtime(true);
if (DBA::exists('workerqueue', ["`priority` = ? AND `pid` = 0 AND NOT `done` AND `next_try` < ?", $priority, DateTimeFormat::utcNow()])) {
$waiting[$priority] = true;
}
self::$db_duration += (microtime(true) - $stamp);
}
if (!empty($waiting[PRIORITY_CRITICAL])) {
return PRIORITY_CRITICAL;
}
$running = [];
$running_total = 0;
$stamp = (float)microtime(true);
$processes = DBA::p("SELECT COUNT(DISTINCT(`process`.`pid`)) AS `running`, `priority` FROM `process`
INNER JOIN `workerqueue` ON `workerqueue`.`pid` = `process`.`pid`
WHERE NOT `done` GROUP BY `priority`");
self::$db_duration += (microtime(true) - $stamp);
while ($process = DBA::fetch($processes)) {
$running[$process['priority']] = $process['running'];
$running_total += $process['running'];
}
DBA::close($processes);
foreach ($priorities as $priority) {
if (!empty($waiting[$priority]) && empty($running[$priority])) {
Logger::info('No running worker found with priority {priority} - assigning it.', ['priority' => $priority]);
return $priority;
}
}
$active = max(self::activeWorkers(), $running_total);
$priorities = max(count($waiting), count($running));
$exponent = 2;
$total = 0;
for ($i = 1; $i <= $priorities; ++$i) {
$total += pow($i, $exponent);
}
$limit = [];
for ($i = 1; $i <= $priorities; ++$i) {
$limit[$priorities - $i] = max(1, round($active * (pow($i, $exponent) / $total)));
}
$i = 0;
foreach ($running as $priority => $workers) {
if ($workers < $limit[$i++]) {
Logger::info('Priority {priority} has got {workers} workers out of a limit of {limit}', ['priority' => $priority, 'workers' => $workers, 'limit' => $limit[$i - 1]]);
return $priority;
}
}
if (!empty($waiting)) {
$priority = array_shift(array_keys($waiting));
Logger::info('No underassigned priority found, now taking the highest priority.', ['priority' => $priority]);
return $priority;
}
return false;
}
/**
* @brief Find and claim the next worker process for us
*
* @return boolean Have we found something?
* @throws \Friendica\Network\HTTPException\InternalServerErrorException
*/
private static function findWorkerProcesses()
{
$mypid = getmypid();
$ids = self::nextProcess();
// If there is no result we check without priority limit
if (empty($ids)) {
$stamp = (float)microtime(true);
$condition = ["`pid` = 0 AND NOT `done` AND `next_try` < ?", DateTimeFormat::utcNow()];
$result = DBA::select('workerqueue', ['id'], $condition, ['limit' => 1, 'order' => ['priority', 'created']]);
self::$db_duration += (microtime(true) - $stamp);
while ($id = DBA::fetch($result)) {
$ids[] = $id["id"];
}
DBA::close($result);
}
if (!empty($ids)) {
$stamp = (float)microtime(true);
$condition = ['id' => $ids, 'done' => false, 'pid' => 0];
DBA::update('workerqueue', ['executed' => DateTimeFormat::utcNow(), 'pid' => $mypid], $condition);
self::$db_duration += (microtime(true) - $stamp);
self::$db_duration_write += (microtime(true) - $stamp);
}
return !empty($ids);
}
/**
* @brief Returns the next worker process
*
* @return string SQL statement
* @throws \Friendica\Network\HTTPException\InternalServerErrorException
*/
public static function workerProcess()
{
// There can already be jobs for us in the queue.
$waiting = self::getWaitingJobForPID();
if (!empty($waiting)) {
return $waiting;
}
$stamp = (float)microtime(true);
if (!Lock::acquire('worker_process')) {
@ -966,7 +918,7 @@ class Worker
}
self::$lock_duration += (microtime(true) - $stamp);
$found = self::findWorkerProcesses($passing_slow, $entries, $deferred);
$found = self::findWorkerProcesses();
Lock::release('worker_process');

View file

@ -616,7 +616,7 @@ class Contact extends BaseObject
DBA::update('contact', ['archive' => true, 'network' => Protocol::PHANTOM, 'deleted' => true], ['id' => $id]);
// Delete it in the background
Worker::add(PRIORITY_LOW, 'RemoveContact', $id);
Worker::add(PRIORITY_MEDIUM, 'RemoveContact', $id);
}
/**