Then PD pulls off an exam which was, not easy, but not the complete enema which I was expecting.

So the exam wasn’t easy as I said, but I managed to do some of the questions, unlike I had expected – I even did the programming question!

Question 1

• A – Define interfaces/classes for a remotely-accessible membership service [12]
• B – Lamport clocks, illustration of wrong orders amongst messages [7]
• C – Token-passing, failure modes, impact on dissemination of messages [7]
• D – Vecotr clocks, description and how it doesn’t solve the ordering problem [4]

Question 2

• A – Spanning trees, building a spanning tree [7]
• B – Description of problem efficiently solved with spanning trees [7]
• C – Spanning trees vs. diffusion trees [4]
• D – Wave vs. Traversal algorithms, either totalling values or finding maximum in a 2-D torus [12]

Question 3

• A – Large-scale distributed file systems, problems, solutions, trade-offs and design issues [23]
• B – Problems when implementing a CMSS [7]

Question 4

• A – Distributed workflows using tuple-spaces. [10]
• B – 2 aproaches to leader election with a tuple-space [10]
• C – Different ways a Byzantine node can disrupt distributed tuple-spaces [3]
• D – Why if > N/3 Byzantine nodes cannot have consensus on common value [7]

I managed to do question 2, which I felt most comfortable then questions 3 and 1. I didn’t have a clue about tuple spaces, having briefly read the notes on them and not feeling too confident about how to use them, there was no way I was going to do a whole question which centered around them!

Anyway, not as bad as it could have been. But then again, I said the same about OS3 last year and it didn’t turn out too well for me! Hope everyone else did shit, and thus making my grade slightly better!
- Chris

So it’s the middle of the night again, this seems to happen to me daily. I’m sitting here at my laptop, thinking about going to sleep then getting up early to carry on working on my DAS exercise. Then I get to thinking about how much I still have to do, then also about how much time I have left to do it… I’ve left everything too late as usual.

So here we have it folks: It’s my first all nighter of this year! I have managed to do way less work than I had hoped to do today. It’s strange how having work to do focuses you to do all those things which you normally have “no time to do”, i.e. when you are sitting on your arse watching TV.

So far today I have:

• Done work on this site
• Watched some TV, not only watched TV but watched repeats of shows I had already seen!
• Read a few more chapters of the new Terry Pratchett book, Going Postal (very good by the way)
• Caught the end half of Blow that my flatmates were watching
• Oh yeah, I also did some DAS.

That extra hour today really helped me cram all those things into it. I’m just looking for more things to do to put off the inevitable work which I will have to get on with. I think this calls for another chapter of Going Postal, followed by some refreshments and then back to the coding. Oh the joy!

I love university.
- Chris