me &= ~grad_school

An unassuming cardboard tube arrived in the mail the other day, containing my MSCS diploma from Hopkins. Thus passes my academic career. I doubt the experience will ever pay for itself financially, but I did learn a great deal, even as a crusty practitioner of some years. Returning to the student life of never-ending deadlines took quite some getting used to, and the corresponding lack of sleep was good training for Alex’s concurrent arrival. (Said arrival also made up my mind to not pursue the thesis option.)

In the main, the classes were excellent, but the small size of the school means the catalog is limited compared to Georgia Tech. For example, I would have liked a class or two on the hardware side. Hopkins only offered the equivalent of GT’s CMPE 2510 (MIPS architecture with the Hennessy and Patterson book).

Through projects and reading papers, I gained a new appreciation for the difficulty of good science, and the prevalence of bad. I’ll always be an engineer first, as I lack the patience to do science well. Banging out a project out in 2-6 weeks was de rigeur; here are some of them:

  • A handwriting recognition program based on HMMs (basic stuff, but I had no prior machine learning experience)
  • A user-space version of mac80211 hwsim. With the simulator, I evaluated the Linux rate controllers for different rates of packet loss, and found and fixed a bug in Pid. There are a few things in Minstrel that can still be improved, but there’s no surprise that it is much better than Pid.
  • A failed investigation into cache-oblivious data structures for filesystems. It’s tough to beat B-Trees at their own game. Still, I’m very excited about CO algorithms since this stuff wasn’t even around when I was an undergrad. Hopefully the right problem will come along.
  • Demand paging and swap support for xv6. This was a class assignment, but I had a lot of fun putting it together. [Code deleted from the internet at prof’s request.] The swap daemon was crap due to time constraints, but most groups didn’t get beyond identity mapping.
  • An evaluation of parallel algorithms on massive graphs. I now have a better appreciation for the ease of implementation, and horrible performance, of barrier synchronization.
  • A streaming categorical ranking system for twitter graphs. Note to NoSQL graph DB developers: Postgres is still much faster.

There are of course writeups associated with all of these, but my latent inner perfectionist is not very happy with most of them. I might revisit them with more rigor if I get bored some day.