A method and apparatus for optimizing quiescence in a transactional memory system is herein described. Non-ordering transactions, such as read-only transactions, transactions that do not access non-transactional data, and write-buffering hardware transactions, are identified. Quiescence in weak atomicity software transactional memory (STM) systems is optimized through selective application of quiescence. As a result, transactions may be decoupled from dependency on quiescing/waiting on previous non-ordering transaction to increase parallelization and reduce inefficiency based on serialization of transactions.