April 16 through April 23

For Lecture, Wednesday, April 16

This is the last lecture on file systems; it covers distributed file systems. In preparation, read Tanenbaum chapter 13 through section 13.2.4.

For Recitation, Thursday, April 17

Read "Disconnected operation in the Coda file system" by Kistler and Satyanarayanan, reading #30. This paper is the second paper in 6.033 that discusses issues related to mobile computing. The first one talked about mobile IP (reading #15); the Coda paper looks at issues when a mobile computer disconnects and reconnects from a file server. Everyone calls Satyanarayanan "Satya."

Here is a question that we have asked in the past on this paper: The paper mentions that scalability was an a priori consideration in the Coda system, as opposed to an afterthought. What mechanisms and policies does Coda implement to achieve scalability, and what are the trade-offs for making Coda largely scalable?

For Quiz 2, Friday, April 18

Quiz 2 will be in Walker during normal class hours, 2-3pm, on April 18. Quiz 2 covers all the material from Recitation 8 (March 4) through Recitation 16 (April 8), specifically networking, naming, and protection and security. This includes lectures 9 through 16. This includes lectures 9 through 16. (You may want to refer to the 6.033-at-a-glance handout for a high-level topic review, or glance over the lecture notes.) But this being 6.033, there is no way we can avoid asking questions that touch on earlier ideas, so don't forget everything you know about complexity and infrastructure. Just as before, the quiz is open book and open note. Quiz questions from previous years are available (see Handouts #27 through #29), and the solutions to those questions will be available on Thursday, April 17.

For Vacation, Monday and Tuesday, April 21-22

Enjoy the Boston Marathon, no lecture and no assignment. Perhaps spent some time on Design project 2, since it is due next Thursday (May 1).

For Lecture, Wednesday, April 23

The first lecture of the last technical topic in 6.033. The topic of this set of lectures is fault-tolerant computing systems. In preparation, read "Chocolate" by Plauger (reading #32) and "Engineering: history and failure" by Petroski (reading #31). These two papers are very short, but provide you with some good insights. Good easy reading. In addition, start reading the paper assigned for Thursday, April 24, reading #33: "High-availability computer systems" by Gray and Siewiorek; in particular, read until the section "Fault-tolerant design concepts" so that you can follow the terminology used in lecture.


System aphorism of the week
An engineer is a person who can do for a dime what any fool can do for a dollar. (Anonymous)

6.033 Handout 30, issued 4/15/96