Really fast, sadly with deadlocks

This commit is contained in:
Michael 2017-06-12 21:39:20 +00:00
parent 1301a29505
commit 228993596a

View file

@ -54,6 +54,12 @@ function poller_run($argv, $argc){
poller_kill_stale_workers(); poller_kill_stale_workers();
} }
// Count active workers and compare them with a maximum value that depends on the load
if (poller_too_much_workers()) {
logger('Pre check: Active worker limit reached, quitting.', LOGGER_DEBUG);
return;
}
// Do we have too few memory? // Do we have too few memory?
if ($a->min_memory_reached()) { if ($a->min_memory_reached()) {
logger('Pre check: Memory limit reached, quitting.', LOGGER_DEBUG); logger('Pre check: Memory limit reached, quitting.', LOGGER_DEBUG);
@ -81,43 +87,31 @@ function poller_run($argv, $argc){
// We fetch the next queue entry that is about to be executed // We fetch the next queue entry that is about to be executed
while ($r = poller_worker_process()) { while ($r = poller_worker_process()) {
foreach ($r AS $entry) {
// Assure that the priority is an integer value
$entry['priority'] = (int)$entry['priority'];
// Assure that the priority is an integer value // The work will be done
$r[0]['priority'] = (int)$r[0]['priority']; if (!poller_execute($entry)) {
logger('Process execution failed, quitting.', LOGGER_DEBUG);
// If we got that queue entry we claim it for us
if (!poller_claim_process($r[0])) {
Lock::remove('poller_fetch_worker');
usleep(rand(0, 200000));
continue;
} else {
// Fetch all workerqueue data while the table is still locked
// This is redundant, but this speeds up the processing
$entries = poller_total_entries();
$top_priority = poller_highest_priority();
$high_running = poller_process_with_priority_active($top_priority);
}
// 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($entries, $top_priority, $high_running)) {
logger('Active worker limit reached, quitting.', LOGGER_DEBUG);
return; return;
} }
// Check free memory // To avoid the quitting of multiple pollers only one poller at a time will execute the check
if ($a->min_memory_reached()) { if (Lock::set('poller_worker', 0)) {
logger('Memory limit reached, quitting.', LOGGER_DEBUG); // Count active workers and compare them with a maximum value that depends on the load
return; if (poller_too_much_workers()) {
} logger('Active worker limit reached, quitting.', LOGGER_DEBUG);
Lock::remove('poller_worker'); return;
} }
// finally the work will be done // Check free memory
if (!poller_execute($r[0])) { if ($a->min_memory_reached()) {
logger('Process execution failed, quitting.', LOGGER_DEBUG); logger('Memory limit reached, quitting.', LOGGER_DEBUG);
return; return;
}
Lock::remove('poller_worker');
}
} }
// Quit the poller once every hour // Quit the poller once every hour
@ -200,7 +194,10 @@ function poller_execute($queue) {
if (!validate_include($include)) { if (!validate_include($include)) {
logger("Include file ".$argv[0]." is not valid!"); logger("Include file ".$argv[0]." is not valid!");
dba::delete('workerqueue', array('id' => $queue["id"])); $timeout = 10;
while (!dba::delete('workerqueue', array('id' => $queue["id"])) && (--$timeout > 0)) {
sleep(1);
}
return true; return true;
} }
@ -210,7 +207,11 @@ function poller_execute($queue) {
if (function_exists($funcname)) { if (function_exists($funcname)) {
poller_exec_function($queue, $funcname, $argv); poller_exec_function($queue, $funcname, $argv);
dba::delete('workerqueue', array('id' => $queue["id"])); $timeout = 10;
while (!dba::delete('workerqueue', array('id' => $queue["id"])) && (--$timeout > 0)) {
logger('Delete ID '.$queue["id"], LOGGER_DEBUG);
sleep(1);
}
} else { } else {
logger("Function ".$funcname." does not exist"); logger("Function ".$funcname." does not exist");
} }
@ -471,7 +472,7 @@ function poller_kill_stale_workers() {
* *
* @return bool Are there too much workers running? * @return bool Are there too much workers running?
*/ */
function poller_too_much_workers($entries = NULL, $top_priority = NULL, $high_running = NULL) { function poller_too_much_workers() {
$queues = Config::get("system", "worker_queues", 4); $queues = Config::get("system", "worker_queues", 4);
$maxqueues = $queues; $maxqueues = $queues;
@ -514,16 +515,12 @@ function poller_too_much_workers($entries = NULL, $top_priority = NULL, $high_ru
$processlist = ' ('.implode(', ', $listitem).')'; $processlist = ' ('.implode(', ', $listitem).')';
} }
if (is_null($entries)) { $entries = poller_total_entries();
$entries = poller_total_entries();
}
if (Config::get("system", "worker_fastlane", false) && ($queues > 0) && ($entries > 0) && ($active >= $queues)) { if (Config::get("system", "worker_fastlane", false) && ($queues > 0) && ($entries > 0) && ($active >= $queues)) {
if (is_null($top_priority)) { $top_priority = poller_highest_priority();
$top_priority = poller_highest_priority(); $high_running = poller_process_with_priority_active($top_priority);
}
if (is_null($high_running)) {
$high_running = poller_process_with_priority_active($top_priority);
}
if (!$high_running && ($top_priority > PRIORITY_UNDEFINED) && ($top_priority < PRIORITY_NEGLIGIBLE)) { if (!$high_running && ($top_priority > PRIORITY_UNDEFINED) && ($top_priority < PRIORITY_NEGLIGIBLE)) {
logger("There are jobs with priority ".$top_priority." waiting but none is executed. Open a fastlane.", LOGGER_DEBUG); logger("There are jobs with priority ".$top_priority." waiting but none is executed. Open a fastlane.", LOGGER_DEBUG);
$queues = $active + 1; $queues = $active + 1;
@ -606,6 +603,52 @@ function poller_passing_slow(&$highest_priority) {
return $passing_slow; 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 $found;
}
/** /**
* @brief Returns the next worker process * @brief Returns the next worker process
* *
@ -613,74 +656,17 @@ function poller_passing_slow(&$highest_priority) {
*/ */
function poller_worker_process() { function poller_worker_process() {
// Check if we should pass some low priority process $timeout = 10;
$highest_priority = 0; do {
$found = find_worker_processes();
} while (!$found && (poller_total_entries() > 0) && (--$timeout > 0));
if (poller_passing_slow($highest_priority)) { if ($found) {
// Are there waiting processes with a higher priority than the currently highest? $r = q("SELECT * FROM `workerqueue` WHERE `pid` = %d", intval(getmypid()));
$r = q("SELECT * FROM `workerqueue`
WHERE `executed` <= '%s' AND `priority` < %d
ORDER BY `priority`, `created` LIMIT 1",
dbesc(NULL_DATE),
intval($highest_priority));
if (dbm::is_result($r)) {
return $r;
}
// Give slower processes some processing time
$r = q("SELECT * FROM `workerqueue`
WHERE `executed` <= '%s' AND `priority` > %d
ORDER BY `priority`, `created` LIMIT 1",
dbesc(NULL_DATE),
intval($highest_priority));
if (dbm::is_result($r)) {
return $r;
}
} }
// If there is no result (or we shouldn't pass lower processes) we check without priority limit
if (!dbm::is_result($r)) {
$r = q("SELECT * FROM `workerqueue` WHERE `executed` <= '%s' ORDER BY `priority`, `created` LIMIT 1", dbesc(NULL_DATE));
}
return $r; return $r;
} }
/**
* @brief Assigns a workerqueue entry to the current process
*
* When we are sure that the table locks are working correctly, we can remove the checks from here
*
* @param array $queue Workerqueue entry
*
* @return boolean "true" if the claiming was successful
*/
function poller_claim_process($queue) {
$mypid = getmypid();
$success = dba::update('workerqueue', array('executed' => datetime_convert(), 'pid' => $mypid),
array('id' => $queue["id"], 'pid' => 0));
if (!$success) {
logger("Couldn't update queue entry ".$queue["id"]." - skip this execution", LOGGER_DEBUG);
return false;
}
// Assure that there are no tasks executed twice
$id = q("SELECT `pid`, `executed` FROM `workerqueue` WHERE `id` = %d", intval($queue["id"]));
if (!$id) {
logger("Queue item ".$queue["id"]." vanished - skip this execution", LOGGER_DEBUG);
return false;
} elseif ((strtotime($id[0]["executed"]) <= 0) || ($id[0]["pid"] == 0)) {
logger("Entry for queue item ".$queue["id"]." wasn't stored - skip this execution", LOGGER_DEBUG);
return false;
} elseif ($id[0]["pid"] != $mypid) {
logger("Queue item ".$queue["id"]." is to be executed by process ".$id[0]["pid"]." and not by me (".$mypid.") - skip this execution", LOGGER_DEBUG);
return false;
}
return true;
}
/** /**
* @brief Removes a workerqueue entry from the current process * @brief Removes a workerqueue entry from the current process
*/ */
@ -791,7 +777,6 @@ if (array_search(__file__,get_included_files())===0){
get_app()->end_process(); get_app()->end_process();
Lock::remove('poller_worker'); Lock::remove('poller_worker');
Lock::remove('poller_fetch_worker');
killme(); killme();
} }