If the table has a clustered index, the optimizer considers the following parallel access methods when the table uses allpages locking:
A parallel partition scan or a parallel clustered index scan, if the table is partitioned and max parallel degree is set to at least 6
A range scan, using max parallel degree worker processes
A serial scan
If the table uses data-only-locking, the optimizer considers:
A parallel partition scan, if the table is partitioned and max parallel degree is set to at least 6
A range scan, using max parallel degree worker processes
A serial scan
