Home CS439

CS439: Principles of Computer Systems

Homework 11 (Woot!), Part 1

Due: 8:45a Friday, May 1, 2015

Part 1 of the homeworks must be submitted electronically. Please refer to the homework turnin instructions.

  1. Explain the steps that an operating system goes through when the CPU receives an interrupt.

  2. Sun's network file system (NFS) protocol provides reliability via:
    • at-most-once semantics
    • at-least-once semantics
    • two-phase commit
    • transactions

  3. Is it fundamentally necessary to store on disk the information about the unallocated disk sectors? Explain why.

  4. Deadlock can exist if and only if several conditions hold simultaneously. What are those conditions? Name and describe all of them.

  5. Considering all the pieces of the operating system we have discussed, describe the steps the OS takes when performing a context switch. Assume that processes are waiting in the ready queue.