/    /  DBMS- Recovery Algorithm

Recovery Algorithm


ARIES recovers from a system crash in three phases.


a) Analysis Pass: This pass determines which transactions to undo, which pages were dirty at the time of the crash, and the LSN from which the redo pass should start.


b) Redo Pass: This pass starts from a position determined during analysis, and performs a redo, repeating history, to bring the database to a state it was in before the crash.


c) Undo Pass: This pass rolls back all transactions that were incomplete at the time of the crash.


Reference Link

Recovery Algorithm