How can developers optimize the performance of PHP sessions when working with large multidimensional arrays?

When working with large multidimensional arrays in PHP sessions, developers can optimize performance by serializing the array before storing it in the session and unserializing it when needed. This reduces the amount of data being stored in the session and can improve overall performance.

// Serialize the multidimensional array before storing it in the session
$_SESSION['large_array'] = serialize($largeArray);

// Unserialize the array when needed
$largeArray = unserialize($_SESSION['large_array']);