Midterm-Fall 2001

You must answer all the questions asked based on the following papers

1. SEDA: An Architecture for Well-Conditioned, Scalable Internet Services, Matt Welsh, David Culler, and Eric Brewer. To appear in Proceedings of the Eighteenth Symposium on Operating Systems Principles (SOSP-18), Banff, Canada, October, 2001. (PDF)
2. Chang, F., G.A. Gibson, "Automatic I/O Hint Generation through Speculative Execution," Proceedings of the Third USENIX Symposium of Operating Systems Design and Implementation (OSDI), February 1999. (PDF).

1. What is the problem the authors try to solve and why is the problem relevant ?
2. What is the basic idea of the solution proposed in the paper ?
3. How does the problem and the solution relate to what we discussed in class so far (could be more than one relationship) ?
4. What are the limitations of the proposed solution ? What prevents the solution to be immediately accepted ? What are the alternatives to the solution presented in the paper ?
5. How is the idea validated in the paper and what is your interpretation of the experimental results shown in the paper ?
6. You are required to sketch a possible implementation of the proposed solution. This may not be fully described in the paper and you may have to use pseudo-code or other representation to describe how do you see the implementation.
   • For the Automatic I/O Hint Generation paper you will have to sketch how the speculative thread would work (you may use real COW instead of software COW).
   • For the SEDA paper you could sketch a simple multi-threaded server design and then show how the server should look like if implemented using the proposed event-driven model.