11. Specialized concurrency control techniques exist for accessing indexes. 12. With version 2.2, concurrency control was implemented at the database level. 13. The most noticeable improvement is undo support, using the adOPTed algorithm for concurrency control . 14. Atomic commitment protocols are intended and designed to achieve atomicity without considering database concurrency control . 15. Practically an additional concurrency control mechanism is always utilized, even solely to enforce recoverability. 16. InterBase's implementation of multiversion concurrency control is commonly called its multi-generational architecture. 17. Transactional memory provides optimistic concurrency control by allowing threads to run in parallel with minimal interference. 18. Before version 2.2, concurrency control was implemented on a per-mongod basis. 19. The originating wave server is responsible for hosting, processing, and concurrency control of waves. 20. Introducing concurrency control into a system means applying operation constraints which typically result in some performance reduction.
