Merge pull request #2346 from annando/1602-poller-user-limits

Poller: Now the user limits can be detected automatically as well
This commit is contained in:
Tobias Diekershoff 2016-02-12 08:17:30 +01:00
commit 8451397857

View file

@ -68,6 +68,10 @@ function poller_run(&$argv, &$argc){
while ($r = q("SELECT * FROM `workerqueue` WHERE `executed` = '0000-00-00 00:00:00' ORDER BY `created` LIMIT 1")) {
// Constantly check the number of available database connections to let the frontend be accessible at any time
if (poller_max_connections_reached())
return;
// Count active workers and compare them with a maximum value that depends on the load
if (poller_too_much_workers(3))
return;
@ -126,15 +130,43 @@ function poller_run(&$argv, &$argc){
* @return bool Are more than 3/4 of the maximum connections used?
*/
function poller_max_connections_reached() {
$r = q("SHOW VARIABLES WHERE `variable_name` = 'max_connections'");
if (!$r)
return false;
// Fetch the max value from the config. This is needed when the system cannot detect the correct value by itself.
// In that case we use the processlist to determine the current number of connections
$max = get_config("system", "max_connections");
if ($max == 0) {
// the maximum number of possible user connections can be a system variable
$r = q("SHOW VARIABLES WHERE `variable_name` = 'max_user_connections'");
if ($r)
$max = $r[0]["Value"];
// Or it can be granted. This overrides the system variable
$r = q("SHOW GRANTS");
if ($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) {
$r = q("SHOW PROCESSLIST");
if (!$r)
return false;
$used = count($r);
logger("Connection usage (user values): ".$used."/".$max, LOGGER_DEBUG);
} else {
// Since there are no user specific limitations we will now check for the system values
$r = q("SHOW VARIABLES WHERE `variable_name` = 'max_connections'");
if (!$r)
return false;
$max = intval($r[0]["Value"]);
if ($max == 0)
return false;
@ -143,25 +175,19 @@ function poller_max_connections_reached() {
if (!$r)
return false;
$connected = intval($r[0]["Value"]);
if ($connected == 0)
return false;
} else {
$r = q("SHOW PROCESSLIST");
if (!$r)
$used = intval($r[0]["Value"]);
if ($used == 0)
return false;
$connected = count($r);
logger("Connection usage (system values): ".$used."/".$max, LOGGER_DEBUG);
}
$level = $connected / $max;
logger("Connection usage: ".$connected."/".$max, LOGGER_DEBUG);
$level = $used / $max;
if ($level < (3/4))
return false;
logger("Maximum level (3/4) of connections reached: ".$connected."/".$max);
logger("Maximum level (3/4) of connections reached: ".$used."/".$max);
return true;
}