Crash Consistency: Recovery Strategies

This lecture covers the importance of crash recovery in file systems, discussing the challenges of maintaining consistency after crashes and the potential for file system corruption. The instructor explains the concepts of synchronous writes, delayed writes, and logging as solutions to handle crash recovery. Various scenarios are presented to illustrate the impact of crashes on file systems and the necessity of maintaining internal invariants. The lecture also delves into the performance trade-offs between correctness and speed in crash recovery mechanisms, emphasizing the need for efficient recovery processes. Additionally, the use of write-ahead logging is explored as a method to achieve both speed and safety in file system operations.