Long running process race condition #21
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Trying to recreate a task after a long running process ends in a race condition in the pdo module (actually any db calls through the pdo module for this task) When you pass the pdo object to the `_testConnection(\PDO $pdo)` function its actually receives the value of the reference to the pdo object. Setting it to null in the catch statement doesn't set `$this->_pdo = null;` only the local `$pdo` variable You need to pass it a reference to the reference To test firstly see what you're mysql timeouts are set to using ``` SHOW VARIABLES LIKE 'wait_timeout'; SHOW VARIABLES LIKE 'interactive_timeout'; ``` put a sleep in your test task longer than the largest one (its in seconds) see a race condition as `$this->_testConnection()` calls `$this->_getPdo();` while `$this->_pdo` stays not null.... and repeat At least this is so in php v5.6.32 mh
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Trying to recreate a task after a long running process ends in a race condition in the pdo module (actually any db calls through the pdo module for this task)
When you pass the pdo object to the
_testConnection(\PDO $pdo)function its actually receives the value of the reference to the pdo object.Setting it to null in the catch statement doesn't set
$this->_pdo = null;only the local$pdovariableYou need to pass it a reference to the reference
To test firstly see what you're mysql timeouts are set to using
put a sleep in your test task longer than the largest one (its in seconds)
see a race condition as
$this->_testConnection()calls$this->_getPdo();while$this->_pdostays not null.... and repeatAt least this is so in php v5.6.32
mh