Worker: Reserve some space for low priority processes

This commit is contained in:
Michael Vogel 2016-10-10 21:01:36 +00:00
parent 9572e12970
commit ef6a23caf3

View file

@ -73,7 +73,7 @@ function poller_run(&$argv, &$argc){
$starttime = time();
while ($r = q("SELECT * FROM `workerqueue` WHERE `executed` = '0000-00-00 00:00:00' ORDER BY `priority`, `created` LIMIT 1")) {
while ($r = poller_worker_process()) {
// Quit when in maintenance
if (get_config('system', 'maintenance', true))
@ -348,6 +348,89 @@ function poller_active_workers() {
return($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;
$r = q("SELECT `priority`
FROM `process`
INNER JOIN `workerqueue` ON `workerqueue`.`pid` = `process`.`pid`
WHERE `process`.`command` = 'poller.php'");
// No active processes at all? Fine
if (!dbm::is_result($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 Returns the next worker process
*
* @return string SQL statement
*/
function poller_worker_process() {
// Check if we should pass some low priority process
$highest_priority = 0;
if (poller_passing_slow($highest_priority)) {
// Are there waiting processes with a higher priority than the currently highest?
$r = q("SELECT * FROM `workerqueue`
WHERE `executed` = '0000-00-00 00:00:00' AND `priority` < %d
ORDER BY `priority`, `created` LIMIT 1", dbesc($highest_priority));
if (dbm::is_result($r))
return $r;
// Give slower processes some processing time
$r = q("SELECT * FROM `workerqueue`
WHERE `executed` = '0000-00-00 00:00:00' AND `priority` > %d
ORDER BY `priority`, `created` LIMIT 1", dbesc($highest_priority));
}
// If there is no result (or we shouldn't pass lower processes) we check without priority limit
if (($highest_priority == 0) OR !dbm::is_result($r))
$r = q("SELECT * FROM `workerqueue` WHERE `executed` = '0000-00-00 00:00:00' ORDER BY `priority`, `created` LIMIT 1");
return $r;
}
if (array_search(__file__,get_included_files())===0){
poller_run($_SERVER["argv"],$_SERVER["argc"]);