Category Archives: Week-15

Read Constantly

An algorithm is a set of rules to be followed in order to solve mathematical problems in numerous steps that usually involve repetition of an operation. Sometimes algorithm problems do not show up at the beginning of a project. As Steven S. Skiena states, different programmers find them out as subproblems, which appear to be … Continue reading Read Constantly

From the blog cs-wsu – Kristi Pina's Blog by kpina23 and used with permission of the author. All other rights reserved by the author.

Journey into “Craft Over Art” (An Individual Apprenticeship Pattern)

On this Software Development Capstone journey part of my assignment is to choose 10 Individual Apprenticeship Patterns out of 35 patterns among Chapters 2-6 from the book Apprenticeship Patterns: Guidance for the Aspiring Software Craftsmanby Dave Hoover and Adewale Oshineye. For my tenth and final individual Apprenticeship pattern I decided to blog about “Craft Over Art” pattern.


The pattern “Craft over Art” is the idea of choosing the craft of programming and making thing functional. Rather than choosing art of programming and making the program look beautiful but not so functional for the customer. Even though you may find an opportunity taking your customer problem and making something nice that will impress your coworkers, it is best that you put the customer needs before your own selfish wants or needs. When it comes to dealing with customer your goal should always be choosing creating a functional valuable product, rather than something else that only advance your own self interest. When dealing with customers it is more important to choose the craft of software development rather than feeding that desire to creating something beautiful, yet not truly functional or deliverable in the real world. This pattern is not telling you that things can’t be beautiful it more saying that whatever you build for your customer must be functional and useful, therefore you must be willing to sacrifice beauty over utility. “The more useful a piece of software, the more important it is that the software be high quality. But quality takes time. You will have to work toward a suitable level of quality by repeatedly making trade-offs between beauty and utility.”

My Reaction

This pattern helps you understand the impotence of building “Craft over Art” because it reminds you that creating something useless yet beautiful is not craftsmanship. I agree with this idea because crating a useful software program far more important than a beautiful non-functional one. I found this pattern to be interesting but also useful and thought-provoking. This pattern has definitely changed the way I think about my profession and the way I think, the reason being is that I should always be willing to sacrifice beauty before sacrificing usefulness.

Thank you for your time. This has been YessyMer in the World Of Computer Science, until next time.

From the blog cs@Worcester – YessyMer In the world of Computer Science by yesmercedes and used with permission of the author. All other rights reserved by the author.

MINIX3: Wrapping Up

I haven’t written a blog post for MINIX3 in some time (sorry Professor), and I figured that it would probably be wise to wrap up what I managed to complete this semester after I managed to get past all the stress I was feeling.

About halfway through the semester I started meeting weekly with my professor in order to discuss ways to approach my project. He knew I was pretty darn stressed about it, but was also pleased with how much I had learned about MINIX3 and Operating Systems in general. When we started meeting, I hadn’t done any actual programming in the scheduler, and I was still fuzzy on how the whole scheduler worked as one unit. I had also not realized this at the time, but the scheduling algorithm in the official MINIX3 Book was an older version. It doesn’t reflect the design found in this report, which describes the current scheduling algorithm (found in versions 3.3.0 and newer, I believe). This was adding to the confusion in how to approach the system, because I was getting my information on the implementation of the scheduler from both sources.

I’ve talked about this a bit in my previous blogs, but I figured I’d recap in this one now that I have a better understanding of the system. In the official MINIX3 book, the scheduler is still built into the Kernel. This meant that any scheduling changes that were to be implemented involved editing kernel code, which could end up being pretty complex in the event of errors, etc. What the scheduling report outlines is the move of the scheduler into the user mode level of MINIX’s layered design system. There still is a small default scheduler that had to be implemented, but the main scheduling policy is implemented within the user mode scheduler.

Let’s talk scheduling policies. Both the kernel-level and the user-level schedulers implement a Round Robin scheduling algorithm by default. As outlined in the report, the easiest policies to implement with the user mode scheduler are round robin, priority, staircase, and some other queue-based policies. Whilst I was googling information about implementing priority-based algorithms, I found this wonderful project done by a GitHub user named Akshita Mittel. It includes a few test files and the changes necessary to make to some of MINIX3’s files in order to implement different algorithms. It is very similar to the project I had intended on doing, so whilst I did not copy it directly (licensing and copyright issues and whatnot), I did use it as a resource for implementing my own project.

Since I wanted to deviate my project slightly from the resources I found online, instead of just implementing more than one scheduling policy, I elected to compare the default scheduling policy with a priority scheduling algorithm, and vary the number of queues by +- 25%. This left me with 3 variations of the default Round Robin policy — one with 12 queues, one with the standard 16 queues, and one with 20 queues. It also left me with 3 variants of a scheduler using a priority algorithm, again with 12, 16, and 20 queues. My goal was to run the same test across each of these 6 variations and see if there was some notable runtime difference.

Before I go into the test, I figured I’d explain the difference between Round Robin and Priority style scheduling. Round Robin policies assign each process within the priority queues a time slice, called quantum. As processes run out of quantum, they’re moved to a higher (the higher the number, the lower the priority) priority queue. In MINIX3, after a certain number of ticks, the queues are rebalanced. This means that all processes who have had their priority changed get that priority reset. The difference between round robin and priority scheduling algorithms is fairly simple — round robin policies aim to be fair, which is why they implement queue feedback. Priority policies are designed without fairness in mind. You might want some processes to always have the highest priority. Therefore, it simply disables process feedback from happening. Processes don’t move around between queues. A diagram of the structure of the priority queues are shown below.

Based on an image from Operating Systems: Design and Implementation by Andrew S. Tanenbaum

The test I used was based on Akshita’s that I found on GitHub. The test program would log system time, do some work with a process, then log the system time again, and find the difference between the start and end times. I found the average running time for 100 tests for each of the variations. The results are displayed below.

As you can see, there wasn’t much consistency across the tests. I’m sure that, before I even ran the tests, I could have reasonably come to the conclusion that there wouldn’t have been much of a difference in run times given my particular approach. The test I ran was mostly CPU bound as opposed to I/O bound, which very well could have made a difference. I think CPU bound tests could have made a bigger impact if I had implemented a different policy than priority. On top of designing a better test for what I was doing in particular, I think that theoretically the number of queues within a round robin scheduler wouldn’t make much of a difference unless the processes existed within them for a very long period of time. Also, I think that the number of queues within a priority scheduler wouldn’t make a significant difference either, since processes tend to live where are they spawned. Aside from the crowding of the queues, I don’t see it having a large impact on the overall runtime. Therefore, I think that the results I got make sense.

I’m not upset that my small “research project” didn’t yield great results. The point of this independent study was for me to better understand operating systems, as I felt as though I was seriously lacking in that area. While I know there’s still a tremendous amount of knowledge to be gained in OS’s, I’m happy with the work I did this semester and feel far more confident when discussing OS concepts in general. It was a very stressful project at first, but now that I’ve wrapped it up, I think it was absolutely worth it. Hands-on operating system practice is a great way to go about learning the subject. In fact, this independent study has sparked quite a bit of interest in systems programming for me, and I’m looking forward to continue learning about it in the future!

(Side-note, this is my last school-related blogpost. At first, I felt extremely uncomfortable writing these things. Now, I think it’s something I’d like to do once a week, or at least regularly. I appreciate my professor requiring us to start these blogs — writing is something I never really saw myself doing enjoying, and after doing it for a couple of semesters now, I get it. Who would’ve guessed that recording what you learn is both both enjoyable and rewarding. Thanks, Professor Wurst!)

From the blog CS@Worcester – James Blash by jwblash and used with permission of the author. All other rights reserved by the author.

Revealing Ignorance

Hello, again fellow readers!

Today we will once again be continuing our journey into software apprenticeship patterns. From last week, we will continue on to the next pattern, Expose Your Ignorance.

This pattern is all about once you have gotten yourself onto a team where you can learn more from your fellow teammates, presumably in a job. The problem is that well… you are ignorant. You need to deliver and you have a lack of knowledge in whatever language or technology you need to be able to deliver.

The offered solution is fairly simple, ask questions and don’t be afraid to show that you are ignorant in a particular subject. You should recognize that it is human to want to appear competent and not appearing competent is not a bad thing. It is all part of the learning process. As a software craftsman, you need to know many different subjects and technologies. The pattern suggests that people who are uncomfortable with the learning process of appearing ignorant become experts instead. They seek out expertise in one particular field and never venture too far from it. Experts are important but the journey of a software craftsman is much longer and requires a broader scope of knowledge. You become an expert in one or several subjects along the way but that is not the ultimate goal. For a software craftsman, one of the most important skills is the ability to learn. To solve this problem the pattern suggests writing down a small list of thing you don’t really understand about your work and posting it in public view.

This pattern I find interesting. What I found most interesting was the distinction made between the software craftsman and the expert. The pattern admits that a software craftsman will likely become an expert in a few subjects but that is not the ultimate goal. The goal is not explained in the pattern (I’m sure it is explained at the beginning but I have forgotten it at time of writing) but the difference between the expert and the craftsman is that the expertise is not the goal. A craftsman goes further than becoming an expert and goes on to craft with the expertise of many under his belt where the expert gains expertise and then rests on his laurels. I do also appreciate the part where it states that by admitting ignorance it will increase your reputation greater than “fake it until you make it” will.

That’s it, for now, my fellow readers. Until next time!

From the blog CS@Worcester – Computer Science Discovery at WSU by mesitecsblog and used with permission of the author. All other rights reserved by the author.

Apprenticeship Pattern – Sweep the Floor

For my last apprenticeship pattern blog post, I felt that the pattern Sweep the Floor was appropriate given where I currently am at in my career, given that I hope to be starting in the very near future. This pattern refers to the scenario in which you’re a new apprentice on a project or a new member of a team and you’re not sure what your place is in the team, so you want to contribute and earn the team’s trust. The solution to this is to volunteer for simple, necessary tasks that no one else wants to do and to make sure to do a great job with them. Of course, you want to make sure that you don’t end up only doing menial tasks that no one else wants to do and that you’re given more challenging assignments after proving yourself “worthy”.

As I said earlier, this pattern is probably one of the most applicable to me at the moment, because once I start I can see myself in almost the exact same scenario as described in the pattern. I always figured that most junior level roles start with you being assigned simple tasks like one-liner bug fixes to help you get acquainted with the code base, but I hadn’t considered that it would be a good idea to take on tasks like literally sweeping the floor in order to build confidence as a member of the team. Of course, I don’t entirely agree with consistently taking on tasks that aren’t relevant to what you want to work towards, but there’s merit in doing menial labor when you happen upon it. As long as you make sure to let it be known that you want to be challenged and not just be comfortable standing still working as the team’s gopher.

Overall, I would say that it’s very likely that I’ll end up using this pattern in the very near future, so hopefully I remember to avoid the negative consequences of applying it. In fact, I wouldn’t be surprised if this pattern would be useful for me anytime I happen to enter a new team, not just my first one.

From the blog CS@Worcester – Andy Pham by apham1 and used with permission of the author. All other rights reserved by the author.

“Record What You learn”/”Share What You Learn”

This is the last blog post for Individual Apprenticeship Patterns, I want to end with “Record What You Learn”. Most of what we were talking about was learning and how to apply it to the real world. I thought this is important because I am also doing this in daily basic. I keep making same mistake, and I learn to avoid it slowly. There are issue I just need to more practice to avoid, but there are mistakes I could have learnt. The book suggests that some platform to write down. Ade uses two instances of the same wiki, one for his private thoughts and the other for stuff he wants to share with the world. That is the good idea, some from my mistakes I didn’t want lets other to know about it. But after this book I wouldn’t mind others to check on my mistakes. They could help me to fix it or at least I will learn from it.

By said that, I also want to connect this to the next pattern “Share What You Learn”. Like I mention above, we could become a journeyman, the ability to communicate effectively and bring other people up to speed quickly. We learn what need to be share and what shouldn’t. It does not matter what you take note for yourself. Before share to others, you need to think if that will have negative effect to them or even to the team. This could damage the relationship of the group. They also suggest that shared as blogpost about the lesson which is soft of what we are already been doing. In blogpost we also could share our solution and have conversation with other.

This is my final thought of the book. I think this book is good on the guideline on the ethics side of the industry. I also have honest advice from experience people. They gave short good example/advice that easy to ready. I am will read the rest of the patterns and keep this book with me.

From the blog CS@Worcester – Nhat's Blog by Nhat Truong Le and used with permission of the author. All other rights reserved by the author.

The White Belt

For this week’s blog I have decided to write about the chapter called “The White Belt” from out textbook. The context of this chapter is that you have developed a deep understanding of your first language but have plateaued and you are rather comfortable with that spot. I find this to be exactly where I am now. I have spent four years writing in Java a majority of the time. I would say that Java is the language I feel most comfortable in, and have the strongest understanding of how it works. Other languages that we have touched upon in my college career such as C and typescript/javascript, I am not as comfortable in because of this lack of depth of knowledge in these languages. This leads us to the problem portion of the chapter, which is that we have problems gaining knowledge of new things when we are coming from a position of comfort. The book points out a fear of personal development coming to a halt, and I think that rings true with me. I am afraid that once I leave college I will not learn as much as I need/want to. I am afraid of being a “one trick pony” with Java. What if my job requires me to code in C? C++? Any other language? I feel right now in this minute that if this were the case, I would be able to get by, but just barely and not very comfortably. And that is a feeling I do not want to have every Monday through Friday in my career! So how do we fix this issue of complacency? The book starts off the solution with a quote from Star Wars, which I thought was genius. The quote is, “You must unlearn what you have learned”. Now this doesn’t mean go and forget Java and all of its syntaxes and learn another language completely. This means unlearn your learning habits, keep your knowledge of Java but also learn to gain a knowledge of another language. Keep doing this, and soon enough you will be a master of programming. I find this solution to be rather comforting as I also find myself in this position of plateau quite often. I am hoping to continue my education of coding long after I leave college.

From the blog CS@Worcester – The Average CS Student by Nathan Posterro and used with permission of the author. All other rights reserved by the author.

Sustainable Motivations

There are many things that can motivate us to be programmers. Some of them can motivate for the long term, while others may not be sustainable. We may become very good at a particular language or framework. This specific expertise may very well translate to a larger paycheck. But if your true goal is mastery … Continue reading Sustainable Motivations

From the blog cs-wsu – Kristi Pina's Blog by kpina23 and used with permission of the author. All other rights reserved by the author.

Sprint 6 Retrospective

Sprint 6 lasted from April 24th to May 6th. This sprint, my group and I had a main goal to focus on completing a powerpoint of our final project to present to the class on May 15th. Unknowingly, we instead spent most of our class time trying to merge and integrate our project with everybody else’s, which in turn broke some of our features and we never fully completed this integration.

While my teammates worked through those issues, I spent a lot of time trying to merge my completed dropdown button feature on to the main branch. This was also unsuccessful, partly due to merge conflicts since minor fixes and contributions were being pushed at the same time I was trying to push my own changes. My feature has been working on my own local branch for quite some time, in fact it was easier to develop the dropdown button than it was to merge it with everybody else’s project.

Working with professor wurst, I created a new branch that included my feature since attempting to push to the main branch wasn’t working. I tried creating a new folder, pulling the most up to date branch on a clean slate, then rewriting my changes in class which only took me about an hour. This plan was also unfortunately unsuccessful. Ultimately, as the deadline for the end of the sprint drew closer, we had to compromise on some of our more ambitious goals in order to start work on the presentation, which was meant to be the focus of the entire sprint.

I was still able to write about the ins and outs of my dropdown button, and I included screenshots from my local running branch. Thankfully, I believe I will have much to talk about. I will explain in depth some of the code lines and how they tie together with the modules and components necessary to make the whole thing work. I also want to include references to where I got the idea for the dropdown, since I stumbled upon a very helpful website that included HTML sample code for me to modify and trim down to fit our projects needs. I lastly will talk about how our work can be improved in the future. Our project contains a lot of filler text and our buttons don’t do much besides display text on the screen. To fit more specific needs, the text can easily be changed and more functions in the HTML can be added without necessarily changing the buttons around. Some ideas would be displaying various messages, videos, or information otherwise that would fit a more specific need depending on who will actually be using the app. Ill include a link to the presentation below this paragraph.

Overall I think we will get a good grade on the project, on our presentation, and on the class as a whole. I enjoyed this class more so than some of the others I took this semester, and I feel that I had more motivation to put in more effort into this class than some of the others.

From the blog CS@Worcester – CS Mikes Way by CSmikesway and used with permission of the author. All other rights reserved by the author.

Study the Classics

Before I became a Computer Science major and aspiring software craftsman, I was very much into reading what many people would consider “the classics”. Whether it was the Iliad and the Odyssey or A Brief History of Time, I have always been fascinated by works of literature that had such significant content or perspectives on the world that they were revered throughout centuries as “the classics”.

So when I came across this pattern, Study the Classics, I immediately resonated with the context they put forth and their motivation for including it in their book. The solution / action which they suggest to us budding apprentices is to collaborate with others and ask about a concept unfamiliar to us and to try and seek out the book which that concept was written about.

Immediately my mind drifted back to learning the Gang of Four’s software design pattern book, which I know for a fact to be highly revered and considered one of the “classic texts” in our craft. Even when I first read it for school assignments, I was enamored by how rich the concepts were and how articulately they were explained. My learning and overall understanding of software development as a whole is unquestionably markedly better than it ever would have been had I not been exposed to this book.

At the same time, I am aware that as good as this book is, and as valuable and timeless as the information in it is, it is definitely not a holy bible for software developers. There can not exist one text to rule them all, because there is no single entity capable of compiling everything we would possibly want or need to know into a single source. So in the future I will definitely seek out multiple individuals or groups of authors who are very well known and revered in our field, so I can add their works to the collection of books I need to read to be as knowledgeable and as prepared as possible for the uncertain road that lies ahead of me in my journey to competence in software development.

From the blog CS@Worcester – Bit by Bit by rdentremont58 and used with permission of the author. All other rights reserved by the author.