CS261 Fall 2016: Quiz #2

45 points: 15 per question

This exam is closed notes, closed papers, closed interwebs, closed everything.

Please use whatever word processing software that you'd like to write your answers, but please send me either plain text (≤ 80 characters per line) or PDF. I will be grading the quiz blind (that is, I don't want to know whose quiz I am grading), so please do not put your name anywhere in your exam. Instead, name your exam lastname.{txt,pdf}. Please email your quiz to: margo@eecs.harvard.edu.

Here are the papers we've read since the first quiz:

  1. Waldspurger: Memory Resource Management in VMware ESX Server
  2. Haggmann: Reimplementing the Cedar File System Using Logging and Group Commit
  3. Rosenblum: The Design and Implementation of a Log-Structured File System
  4. Sandberg: Design and Implementation of the Sun Network Filesystem
  5. Howard: Scale and Performance in a Distributed File System
  6. Min: SFS: Random Write Considered Harmful in Solid State Drives
  7. Rumble: Log-structured Memory for DRAM-based Storage
  8. Schroeder: Experience with Grapevine: The Growth of a Distributed System
  9. Anderson: Serverless Network File Systems
  10. Stoica: Chord: A Scalable Peer-to-peer Lookup Service for Internet Applications
  11. Rowstrom: Storage management and caching in PAST
  12. Ghemewat: The Google File System
  13. Mickens: Blizzard: Fast, Cloud-scale Block Storage for Cloud-oblivious Applications
  14. Dean: MapReduce: Simplified Data Processing on Large Clusters
  15. Baumann: Shielding Applications from an Untrusted Cloud with Haven

  1. Tips for Building Distributed Systems
  2. We've read many papers on distributed systems, mostly storage systems. Many of these papers include principles for building distributed systems that scale. List five such principles and cite the paper from which each came.

  3. Tradeoffs in log-structured storage
  4. Part A

    We read three papers that use log-structured storage. Which three were they and for what media was their design intended?

    Part B

    Each of the systems chose log-structured storage, even though they were targeting radically different environments. Explain how the applications of log-structured storage differ between the papers and explain how the differences reflect the different environments in which the storage was deployed.

  5. Statelessness versus Stateful Systems
  6. NFS and AFS take exact opposite positions about whether a server should retain state about its clients.

    Part A State the position taken by each system. Then give one example where each system is simpler, better, or higher performing than the other, because of their decision regarding state.

    Part B

    Pick one other distributed system that we read about and indicate whether it is stateful or stateless. Then discuss how it addresses the challenges (or the negatives) that arise for a system of that type.

BONUS PROBLEM (2 points)

What is the answer to the "coming to class on time" question?

Paper Survey

After you complete the quiz, please complete this form .