Optimistic Concurrency Control – Broadcast Commit (OCC-BC) in Real-Time Database.
Optimistic Concurrency Control – Broadcast Commit (OCC-BC)
- Transactions are reading and writing the required data items freely without any blocking.
- When any of the transactions reaches commit, then that transaction broadcasts the decision to other concurrently ongoing transactions.
- Upon receiving this message, each ongoing transaction checks whether they have any conflict with the about-to-commit transaction.
- If any transactions find conflict with the about-to-commit transaction, then those transactions aborts and restarts immediately.
- If a transaction reaches commit (the validating transaction) and broadcast its decision, the commit is guaranteed.
- The method detects conflicts earlier than the basic OCC algorithm, resulting in both, earlier restarts and less wasted resources, which increases the chances of meeting transactions’ deadlines.
- It does not consider priorities.