Commit Protocols Flashcards
(8 cards)
What are the ACID properties?
Atomicity, Consistency, Independence, Durability
What is the point of commit protocols in transaction systems?
Ensure all nodes commit or abort a transaction as a unified decision
When is a transaction in danger of a dealock?
When a transactions response to a conflict is to wait for a lock.
Name a way to avoid deadlocks.
Extinction
Locking and Extinction ensures what ACID properties?
C and I
What are the phases of 2-phase commit protocool?
- Coordinator collects yes/no from all servers
- Coordinator enforces the decision (commit/abort)
Why is 2PC blocking?
If coordinator crashes in phase 2, servers in “wait” state will be waiting for recovery
How does 3PC differ and improve over 2PC?
Adds a pre-commit state to reduce blocking.