Optimistic Locking Concurrency Control Scheme for Collaborative Editing System Based on Relative Position.

In order to meet the requirements of high responsiveness and unconstrained collaboration in real-time collaborative editing systems, this paper proposes a novel multi-granularity optimistic locking scheme for concurrency control in collaborative editing systems based on relative position. In the proposed scheme, reading lock and editing lock are taken into account, and the start position of locking region and that of operation are relative, and they are not transformed into absolute positions until operations are sent to collaborative sites or locks are added into lock table. Additionally, the granularity of lock can be selected by co-editors optionally, and any co-editor can edit the locking region without being blocked before his/her requested lock is confirmed. The application case study shows that this concurrency control scheme has advantages of high responsiveness, unconstrained collaboration, and good data consistency maintenance. [ABSTRACT FROM AUTHOR]