Hi,
We are also facing the same issue. We just upgraded on last weekend.
Please let us know if anyone facing the same or any solution.
Error log:-
[21-Apr-2021 10:06:12 UTC] PHP Fatal error: Uncaught PDOException: SQLSTATE[HY000]: General error: 2013 Lost connection to MySQL server during query in journals/lib/pkp/lib/vendor/doctrine/dbal/lib/Doctrine/DBAL/Driver/PDOStatement.php:115
Stack trace:
#0 journals/lib/pkp/lib/vendor/doctrine/dbal/lib/Doctrine/DBAL/Driver/PDOStatement.php(115): PDOStatement->execute(NULL)
#1 journals/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connection.php(370): Doctrine\DBAL\Driver\PDOStatement->execute()
#2 journals/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connection.php(664): Illuminate\Database\Connection->Illuminate\Database{closure}(Object(Illuminate\Database\Query\Expression), Array)
#3 journals/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connection.php(745): Illuminate\Database\Connection->runQueryCallback(Object(Illuminate\Database\Query\Expression), Ar in journals/lib/pkp/lib/vendor/laravel/framework/src/Illuminate/Database/Connection.php on line 671