Random Walk of Life

Opening Mood: Hungry..
Opening song: Hamesha tum ko chaaya - Devdas

Got the official mail today morning. The “Power Aware Scheduler” Birds of Feathers Session Proposal that I had submitted for this year’s Ottawa Linux Symposium has been accepted. The rest of the BOFS can be found –> here

A couple of days back, Vaidy got confirmation that the paper “Energy-aware task and interrupt management in Linux” of which I am a co-author, has been selected! So it’s great news on the work front!!

The rest of the papers for this year’s OLS can be found –> here

OT, it has been a pretty silent day in my mailbox. I was wondering if everyone decided to take a mass-vacation or something! Only later I came to know that vger.kernel.org is down.

With only a few weeks left to turn in the paper, we should start writing soon! The data is pretty much there with the many experiments that Vaidy has been running for quite some time now.

And me, I am have started using qgit to track the CFS development from it’s inception to it’s present magnificent form! The latest qgit-4 which uses qt-4 looks pretty cool! Much better than the earlier 1.5.5 version

Until next time,
Ciao!

Closing Song: Laree Chooti - Xulfi, Ek-Chaalis ki last local
Closing Mood: Really  hungry!

Opening Mood: I’m back!
Opening Song: Romantic Piano - Chopin

Spent the last week at this place called Kudremukh. It used to be one of Karnataka’s famous mines before the operations were shut down in 2005. So now it is just a nice little place with lots of greenery and very few people to bother an occasional guest. Which was me

I started from karkala on 4th Feb at 8:00 AM to Kudremukh. I had booked a room for myself at the Sahyadri Bhavan lodge for five days through some family contacts. Reached the place at around 9:30 A.M. The ride was very good, and one could spot a lot of trees and forests on the way. Once you cross the Mala outpost, the weather becomes quite pleasant owing to the trees around.

The room where I was put up was really a big one. It had three beds, a balcony, and an attic! All for an extremely cheap then of Rs 200 per day! The guest house has a small restaurant which serves breakfast, lunch and dinner. Again, at very affordable rates. I liked the food there. But then, I also stayed for four years at NITK Surathkal and survived the mess food. So I really shouldn’t be talking about how good the food at any place is . The place also has a very nice town park where I used to go in the evenings for a stroll.

The purpose of the vacation was to do stuff which I had always wanted to do, but never got the time. Starting problem you can say . Over the past couple of years, I have been accumulating quite a bit of technical stuff to read, and the list was only growing. So I wanted to take some time off and get started on some of those items.

Thus I had five days at a place with very little disturbance and an awesome climate. Really, I couldn’t ask for more. The working style was simple. Start with one work item, when you get bored, move on to the next one. There were no other rules. No hard deadlines to finish this or that by the end of 5 days. Just have fun

So, in the five days, I read through parts of Linux Memory management. Two years of programming the kernel, and I was still not aware of how Linux manages the memory across the various platforms it supports. So I had to go back to the very basics, starting from the 386 memory management model and then how Linux represents it using a 4 level model. After that, I read up on the Zoned Buddy Allocator, the Slab Allocator and a part of Process address space. I was using “Understanding the Linux Kernel, 3ed” and 2.6.24 kernel code as reference.

Other than that, RB-trees was something I read about and implemented during this time. It reminded me a lot about AVL trees, which we had studied in our data-structures classes. RB-trees was actually easier to implement (atleast the deletion part).

Also, read the first three chapters from Ulrich Drepper’s “What every programmer must know about memory”. The paper is true to it’s name. Especially the chapter on caches. The paper gives a very clear picture of the implications of having different levels of caches, how the cache size matters, through various well designed experiments. It should be read by anyone who is interested in doing any kind of system programming.

Other than these, did a whole bunch of fun stuff, like wrote a ascii visualization tool for trees. One of the problems I had with the Data structures lab assignement was that we had to show the output through an inorder, or a breadth order traversal. And that was not always very easy to visualize. But then I was one of those who did the class assignments when there was only one or two days left for the deadline. So I guess I am doing all the supplemental things now

Oh yeah, spent a whole evening reverse engineering this obfuscated C Code which prints the poem about the various gifts given by the true love on each day of Christmas. Am planning on writing a small article on that. How recursion was used in place of loops and how the ‘,’ operator was used for statements. It’s a code when you see, you’ll go “This hurts my brain!” . Check it out here.

And when I had time to spare, I read some chapters from Jon Bentley’s “Programming Pearls”. Another book which I would recommend to anyone interested in serious programming. This book sure is fun!

So, now that I am back, the first thing to do would be to catchup with a week of email. Oh well

Closing Song: Marriage of Figaro - Mozart.
Closing Mood: Anxious to catch up with last week’s happenings.

Opening Mood: Chillout and relaxed. NZ cruising along against Canada.
Opening Song: Dooba Dooba - Silk Route
Time: 9:15 P.M, 22nd March 2007.

I visited Indian Institute Of Information Technology Bangalore (IIITB) today to deliver a lecture on “Kernel Synchronization Primitives”. This being my first official technical lecture, I was quite anxious asto how it would turn out. Turned out to be pretty good. But more on that later.

The IIITB campus is situated in Electronics City, a prominent IT tech-park in Bangalore. That’s quite a distance from the place where I stay. So I had to start pretty early in the morning. I travelled to Madivala Bus stand, where I boarded the 8 A.M 356C Volvo bus. I thought it might take me an hour or so to reach Electronic City through the busy and dusty Hosur Road. But to my surprise, the volvo reached Electronic City at 8:30. That was pretty early since my lecture was scheduled at 10.AM. So much for all the cautious advice given by my office folks.

Anyway, IIITB is just a ten minute walk from the main entrance to Electronic City. As I entered the campus, the security guard stopped me. I guess he mistook me for a student without an ID! Gah! I had to explain, that I was here to deliver a lecture and not to attend one

At the reception I found Babita, a 2nd Semester student was waiting for me. I was led into a conference room, where I spent some time checking my mails and chatting with the students. Surprisingly, even IIITB has the static IP scheme. I don’t realize why universities prefer static IP addresses instead of opting for DHCP. First at NITK and now IIITB.

I was escorted to the lecture hall at 9:45. And I must admit, I am very much impressed with the design of the hall. Around 120 students can be accomodated in the lecture hall. They have a control room from which all the projectors and the microphones can be controlled. There were five screens in total. Two of them were projecting my Thinkpad screen. There was a SmartBoard which really impressed me. Hats off to the inventor, whoever it is.

It’s nothing more tha a big touchscreen board connected to a laptop using a USB cable. The laptop has to run the Smartnotes software, whose image was projected on the touch screen. So you write anything on the touch screen, it transmits the points of contact over the USB cable into the laptop, and the SmartNotes software maps the point of contact onto the laptop screen, thereby actually “drawing” what you drew on the touchscreen. And that’s projected back on the touchscreen, giving the effect that you’re actually drawing something on the touchscreen! A very neat concept if you ask me. There’s more to it. You need not erase everytime you have filled up the screen. You just click to go to a new page! The students don’t need to take down the notes as each of “pages” on the screen can be saved as a jpeg/pdf file and mailed to the students. That’s one smart use of technology as a teaching aid.

I started the talk at 10:00 A.M sharp and the hall was pretty much filled up. I hope it wasn’t due to the attendence constraints because of which I used to attend most of the seminars in my college days! At 11, we took a 10 minute break and the second part of the lecture went upto 12:15. I know, I know, I overshot but this is Synchronization - a topic on which I can go on and on for hours. I could find quite a few interested faces among the crowd. And there were a few interesting queries as well.

I am extremely glad that Dr.Shrisha Rao, my host at IIITB is organising talks by the industry folks on the subjects which the students are currently studying. This would definitely give them an insight into the relavence of what they learn in computer science theory.

By the way, after the lecture got over, the students gave me a cool IIITB T-shirt as a memento. Now, how cool is that?!

I am looking forward to more such opportunities. After all, as the great VishwaKnuth once said, “Kutching is my birthright”

Closing Song: O Sanam - Lucky Ali.
Closing Mood: NZ could have done better. But not bad.