Cascading Aborts
Abort of T1 requires abort of T2!
What about WW conflicts & aborts?
- T2 overwrites a value that T1 writes.
- T1 aborts: its “remembered” values are restored.
- Lose T2’s write! We will see how to solve this, too.
An ACA (avoids cascading abort) schedule is one in which cascading abort cannot arise.
- A Xact only reads/writes data from committed Xacts.