Computer System Engineering

Week 9: Distributed Systems Part II

Lecture 16: Atomicity via Logging

Lecture 16 Outline

1. Introduction
2. Motivating Example
3. Basic Idea
4. How to Use a Log for Transactions
5. Performance of Log
6. Cell Storage
7. Performance of Log + Cell Storage
8. Improving Performance
9. What about Un-undo-able Actions?
10. Summary

• Detailed Outline

Lecture Slides

• Lecture 16 Slides: Atomicity via Logging (PDF)

Reading

• Book section 9.3

Recitation 16: Log-Structured File System (LFS)

• Read “Log-structured File Systems (PDF)” by R. & A. Arpaci-Dusseau
• Log-Structured File System (LFS) Assignment

Hands-on Assignment 6: Write Ahead Log (WAL) System

(Not available to OCW users.)

Lecture 17: Fault Tolerance: Isolation

Lecture 17 Outline

1. Introduction
2. Serializability
3. Conflict Serializability
4. Conflict Graphs
5. Interlude
6. Two-phase Locking (2PL)
7. Performance Improvement: Reader-Writer locks
8. Another Possible Performance Improvement: Giving up on Conflict Serializability
9. Summary

• Detailed Outline

Lecture Slides

• Lecture 17 Slides: Fault Tolerance: Isolation (PDF)

Reading

• Book sections 9.4 before 9.4.1 and 9.5

Recitation 17: Databases

• Read “Concurrency Control and Recovery” by M. J. Franklin
• Databases Assignment

Tutorial 9: [No Tutorial this Week]