Mark Turansky

Business, software, and gardening. That's all.

Very Old School — Walking down memory lane

Apr 20

Posted by Mark Turansky in Engineering | 1 Comment

I vividly remember when my neighbor two doors down got an Atari 2600 in 1978. I was probably 4 1/2, maybe 5, but I remember the first time I saw Space Invaders. It was the only game they had. My brothers and I pooled our allowances for a while and bought our own. Combat quickly became my favorite game. You could ricochet bullets from the tanks off the walls! My brothers didn’t stand a chance.

Fast forward to 2008 and I decided to go find an Atari emulator. A few minutes later, I was playing Space Invaders again. Combat in the emulator wasn’t fun because I had no one to play with.

space_invaders.png

 

I really cut my computer teeth on the C64. I remember when I’d walked into Electronics Boutique in the mall and see a wall full of C64 games. A few years later, there was a small “IBC PC” games section. The C64 was great. I spent a lot of time playing games on my C64, but I’d also try to write programs. I remember I was able to make a few basic sprites move across the page, but I had no idea what sprites really were. I remember trying to type in programs I’d find in a book or computer magazine. They never worked. All that mattered to an 8 or 10 year old is playing games.

There was one game in particular that I really fell in love with on the C64: Ultima IV, Quest of the Avatar. It exposed me to my first game with any depth and to a persistent world that I’d live in while playing the game. I was mesmerized. I spent countless hours exploring every nook and cranny in Britannia, figuring things out (I copied the game and didn’t have the manual), immersing myself in the story, and I loved every minute of it. I was probably 11 or 12 years old.

A close friend of mine always had a PC. I remember playing games with him on his 286 and 386. Police Quest and Chopper Commando were our favorites. He had to start the games from the command line.

All the time we had a computer, we used it for word processing. I’d type book reports or other papers on the computer and print them on my dot matrix printer. During my early college days, I worked for a small financial planning firm where I maintained their software (by keeping versions up to date with frequent update disks from insurance carriers and other financial services firms) and created spreadsheets for the agents in Lotus 1-2-3. I’d never even heard of Excel, but I’d gotten my first exposure to early Windows. I think it was Windows 3.1.

I left school to enlist in the Navy where I qualified to train as a Navy Intelligence Specialist. After training, I deployed to the USS Independence in Japan, where I pulled intelligence reports from a computer in the SCIF for the ship’s intel officer. Little did I know it, but it was the internet. Well, it was the government’s classified version of the internet, but looking back now, I can clearly remember clicking on links, printing the pages, and preparing a report for the department Commander.

After the Navy, I went back to finish school. A few of my friends had just gotten email and they told me to look into it. I remember using Pine in the school library to read my email. I didn’t have much email then.

I don’t remember how I learned of it, but my life changed when I learned that Ultima Online existed. Here it was, the game I loved at a kid, the world I spent years exploring (literally, through Ultima 4, 5, & 6), in a new online game!

I bought my first computer explicitly for the purpose of playing Ultima Online. It had a 300Mhz processor, 64mb of RAM, and I forget the size of the drive. It ran Windows 98. And that was the biggest timesink I had heretofore discovered in my life.

Soon, I ran across Ultima Offline eXperiment (UOX), which was (still is) an open source version of UO Server. It was created by a group of hackers to run the UO client. It allowed someone to have their own private game server with a world devoid of people except for those you invite. I remember I organized a tournament with 8 people with me both playing and hosting the server. I didn’t know anything about performance then, but I can laugh at myself in retrospect for thinking I can host 8 active players in a networked game on a 300Mhz machine. It crashed all the time, but it didn’t matter. I was completely amazed that people could do this. I browsed the source code. I knew it was something called “C++”, but I had no idea what I was looking at, yet I thought it looked beautiful. It may have been a kludgefest of cruft for I know, but I fell in love with code, with how it looked, and with what it could do.

So I decided to learn what this code stuff was all about. I bought Sam’s Teach Yourself Java in 21 Days. I installed Java 1.1 and learned Hello, World. Soon thereafter I was writing a program to feed a Jabbywocky. I still don’t know what a Jabbywocky is. I didn’t finish the book. Some of the concepts were over my head, and I could tell that it was all trite and contrived. I wasn’t going to be able to run a UO Server emulator after reading that book.

Still, something stuck and I kept learning new things. I learned HTML, JavaScript, and then ASP (using JavaScript). My first job out of college required me to make reports, so I learned SQL to pull data. Then I applied my new ASP skills to automate the reports. I’m lazy and grew bored with report-making. A few years later, I learned Java for real.

Here we are, a decade later, and I’m busy integrating legacy applications into our shiny new message bus. It’s highly concurrent, runs all our integrated applications in a single JVM but in isolated classloaders, and my company is porting all our automation and data processing to my message bus for integration. It’s got massive horizontal scalability capabilities. Our Linux servers have multiple processors with multiple cores that are 100x faster than my first PC and have 500x as much memory.

This current project of mine is a long way from Space Invaders. I guess 30 years will do that for you. It’s been fun thinking about how I’ve been involved with computers and software in some way (even as a consumer) for my entire life. I’m looking forward to another 30 in high technology and I’m excited to play a part. I might even learn what a Jabberwocky is.

Why Linux will never be the world’s primary desktop

Apr 2

Posted by Mark Turansky in Engineering, Technology | 16 Comments

Every year for the past N years has been proclaimed as “The Year of Linux on the Desktop!” It hasn’t happened. It will never happen.

Why?

GNOME vs. KDE? Which distro?

I understand that Linux is the kernel and that GNOME/KDE is the desktop. I am well aware of this distinction. Joe Average User is not. Joe Average User runs Windows because that’s what came installed with his machine from BestBuy. Jane Schmancy User might be using a Mac, but OS X came pre-installed when she bought her machine. In both scenarios, the computers Just Work™ when they brought them home and booted them up. It’s a packaged experience where the value-add of the OEM vendor is the preconfigured-everything-work-out-of-the-box.

Enter Linux.

First, you have to download a distribution. Which one? With this single step, you’ve lost 95% of the people.

Second, you have to install the OS. It’s a well-known fact that 98.87823423% of the people don’t know what an operating system is nor do they care. They want to vote for their favorite American Idol, not worry about what it means to walk through Anaconda’s install process.

The Free Open Source Software community (of which I am a fervent supporter) believes that choice is a good thing. They are wrong. Less is more, particularly when it comes to making choices. This is the paradox of choice.

The group of people in the world who likes more choice when it comes to operating systems is vanishingly small.

I’ve got CentOS on a desktop at home. I’ve installed Ubuntu on a work machine. Damn Small Linux is our OS of choice for our message bus. I’m in the minority of users. It takes one to know one.

The real reason people won’t switch desktops

It’s different.

That’s it. In a nutshell, “it’s different” will keep the vast majority of users from switching desktops. Joe and Jane Average User barely know Windows, I don’t expect them to voluntarily want to be a newbie on another system. No one likes being a newbie, especially when they’ve achieved some level of mastery of something.

One of my teammates (we’ll call him “Dan”) just got a MacBook Pro to replace his aging Windows laptop. Dan is among the technical elite. He chose Damn Small Linux for our server OS. One week later, he’s lamenting the fact that he’s not as productive on his new machine because he has to learn all new ways of doing things. He briefly considering remapping all the Mac hot keys to match the Windows hot keys he was used to.

When a tech master is considering remapping hot keys, Joe Average User is lost!

The average user doesn’t use hot keys, doesn’t know what they are, and certainly doesn’t know how to remap them. If they even manage to install a new OS, they’ll be lost when looking to run their programs; they won’t get the dumb joke in KDE where every app has to start with a K (Kommander? Konquerer? Kalculator? Please.)

The rise of Mac OSX?

If there will be another desktop to challenge Windows — and that’s a pretty big IF — it will be Apple’s wares. They’ve got the iPod and the iPhone leading the way. They’ve got a much cooler brand than Microsoft. They are trickling into the enterprise market (our CEO uses a Mac, for example, as does our creative staff, media department, and several developers).

Still, “Think Different” becomes “it’s different” for the average user. The person switching from Windows to Mac will be on the right side of the bell curve. The billion PCs out there in the world (and growing) will be running Windows for a long time.

I’m writing this from a Windows laptop. Of the 12 people I can see in my immediate field of vision, only Dan has a Mac. One runs Ubuntu in a VM on his Windows laptop. The rest are running straight Windows.

This article isn’t meant to be a comparison of desktops, features, security, reliability or anything else. I’m just calling it like it see it in terms of usage. The word “never” in the title makes my position an absolute. Perhaps I should modify it to say “Why Linux won’t be the world’s primary desktop for a looooooooooong time, if ever.”

I’m sure some will disagree.

“Don’t Make Me Think” applies to your code, too

Mar 27

Posted by Mark Turansky in Code Hints, Design, Engineering, HOW TO | 4 Comments

Don’t make me think. That’s how I feel about your code.

Or as Martin Fowler puts it:

“Any fool can write code that a computer can understand. Good programmers write code that humans can understand.” -Martin Fowler, Refactoring: Improving the Design of Existing Code

You’ve reached a whole new level of mastery when you write for simplicity, elegance, and maintainability. This is done on purpose, and it’s hard to get right. Deadlines, schedules, pressure, and stress all encourage us to cut corners and adopt a “Git ‘er done!” mentality. But Abandonment of planning under pressure is one of software’s classic mistakes. It’s a cardinal sin.

How do you write simple and maintainable code? I’ve got a 3-step program for you:

Step 1: Admit that simple isn’t easy

Designing simple software is hard. It has to be done on purpose. You can’t accidentally find yourself with well-written code and an elegant solution, it has to be written that way on purpose.

This admission is a bedrock principle required for designing great software and products. If you can’t admit that simple is Hard Work™, you haven’t hit rock bottom yet by having to maintain code that would make readers of The Daily WTF blush.

Step 2: Read “Don’t Make Me Think”

Steve Krug’s excellent book “Don’t Make Me Think” is about website usability, yet it changed how I look at my code.

Why? Because Steve applied the same principles in his book to his book! And if it works in those two mediums, I thought it just might work for me, too, in my medium (code).

“Don’t Make Me Think” is very easily absorbed because he’s feeding you information in a readily accessible way. He wrote it simply on purpose, and I’m certain it took many more hours to edit than it did to write. Simple is hard.

Step 3: Practice simple everyday

There are innumerable decisions you make everyday that affect your project for better or worse. You need to recognize these as the opportunities they are. Here are a few things you can do every day:

  • Code in plain English. Use an active voice (just like writing). What do you think this method does?

    • dao.findCustomerBy(order);

    Or what about this if statement?

    if(admin.hasPermission(Permissions.VIEWFILE)){
       // allow...
    }

    or better yet…

    if(admin.hasViewFilePermission()){
       // allow...
    }

    The pretty method on the Admin class looks like this:

    public boolean hasViewFilePermission(){
       return hasPermission(Permissions.VIEWFILE);
    }

  • Make Stuff Obvious. Quick, what does this line of code do?

    • Date dt = march(28, 1973);

    When I’m reading through unit tests, I’d much rather see the above statement to create a date than the equivalent Java:

    Calendar cal = Calendar.getInstance();
    cal.set(Calendar.MONTH, Calendar.MARCH);
    cal.set(Calendar.DATE, 28);
    cal.set(Calendar.YEAR, 1973);
    Date dt = cal.getTime();

    You can find those convenient date methods here: dates.java (it’s Free software). Use Java 5’s static imports to make the short date seen above.

  • Be Merciless. Be your own worst critic when reviewing your code. Always strive to improve what you’ve written. Just as great essays and novels (and books like “Don’t Make Me Think”) require several rounds of editing, so too does your code.

  • Never nest ternary statements. ’nuff said.

  • Write comments, but be brief and explain why your code does what it does, not how it does it. We already know how it does it, we’re looking at the code.

    • That’s it. Three steps to better code. Putting it into practice won’t be easy, but if you want to be a master of your craft you’ll embrace the challenge and write things simply on purpose. The people who follow you and maintain your code will appreciate it.

    No one should work alone. Ever.

    Mar 25

    Posted by Mark Turansky in Engineering | 10 Comments

    No one should work alone; not in design or planning or coding or any other aspect of software development. Why?

    Nobody gets it right the first time. Nobody.

    Moreover, different people have difference experience. I’d be foolish to think I could write something as good as someone who’s already done it. You cut down on rework issues but tapping into others’ experience. You get it closer to right the first time by having others help think through the issues surrounding a design, and often by watching over your shoulder as you write code. Even then, no one gets it exactly right the first time, but you won’t be nearly as far off as you would be by yourself.

    Xtreme Programming advocates pair programming on all production code. Not all code needs to be written by a pair, in my opinion; most is just fine for a single programmer, but that programmer should never be coding in isolation. Everyone on my team is involved with 100% of the project. We all know everything that is going on and we can jump in at any spot. Any non-trivial code is discussed by the entire team so that we can understand the best path to take. Not only does this help find flaws earlier in the process, it also gives all team members a keen understanding of the entire project.

    Two separate incidences came up today that drove the point home for me.

    First, a co-worker and I were profiling a piece of slow production code. We found a bottleneck and discussed a solution. His original fix would have worked, but it wasn’t as elegant as another piece of code I was able to point to that faced a similar problem and had an elegant solution. We only came to the right solution because we were working together on the same problem.

    Later, another teammate discussed a Spring classloading issue with me (It was a tricky issue surrounding the generation of classes in Hibernate in Spring and having more than one instance of this in the same classloader). He and another coder came up with a solution that would have worked around their problem, but I was able to talk about an experience I had nearly two years ago where I was asked to find and fix a disastrous memory leak in our production servers. Both issues involved class generation in Spring and Hibernate, and I was able to set them on a new path. They are going to tease apart the distinct pieces of software from the monolithic whole and deploy them as separate components on our message bus. All our components are deployed in isolated classloaders, which will solve their problem.

    The older issue involved the constant instantiation/initialization of a Spring ApplicationContext, where each instance caused the generation of Spring proxy classes and Hibernate DOAs. Classes once loaded are never unloaded from a JVM. This was our memory leak. The issue manifested itself at login, and our QA department did not login thousands of times a day like our users do. Code complete doesn’t mean you’re done. You’ve got abuse your system to find bugs like this.

    I can’t begin to count the number of times I’ve asked for help with the design of a tricky piece of code only to find I was going about it entirely the wrong way. Oftentimes, people with a fresh pair of eyes will see things differently than you do. This does, of course, require egoless programming and smart teammates. If don’t have either, well, you’re project has bigger problems than we can solve here.

    Doesn’t all this review and pair programming and constant communication decrease productivity? I’d argue no. In fact, as an investment of time, it’s paying rich dividends in decreased maintenance costs, robust production deployments, and higher morale during a time when other projects are struggling to pay off their design debt. We’re swimming when most others are just trying to tread water.

    I’ve done the solo thing. I’ve also lead or been part of smart teams with tight communication. Pair programming is always the natural result of open communication and egoless programming as the team works together.

    I know which one I prefer. How about you?

    Running the numbers for Risk

    Mar 9

    Posted by Mark Turansky in Entertainment | 5 Comments

    Months ago, I rummaged through the bargain bin at Best Buy and found Risk (the board game) for the PC. I used to have a lot of fun with this with my friends when I was younger, so I thought “what the heck!” and bought it.

    Being a board game geek, math nerd, and computer programmer, I wrote a program to calculate the odds of winning Risk™.  My program ran through all the scenarios thousands of times, spit out the data, and I made some charts in Excel.

    Without further ado…

    Here is a chart showing your odds of winning a fight in Risk™:

    risk_chanceofwinning.png

    But what about after you win? How many armies can you expect to have left? This should be an important piece of your strategy.

    Here is the chart showing your remaining armies after the battle:

    risk_armiesremaining.png

    You can download the source code for the program, too.  Here’s the link: Java program to caculate odds in Risk

    Creative Commons License

    This work is licensed under a
    Creative Commons Attribution-Noncommercial-Share Alike 3.0 United States License.

    Scalability & High Availability with Terracotta Server

    Mar 7

    Posted by Mark Turansky in Architecture, Engineering, Technology, Terracotta | 4 Comments

    Our message bus will be deployed to production this month. We’re currently sailing through QA. Whatever bugs we’ve found have been in the business logic of the messages themselves (and assorted processing classes). Our infrastructure — the message bus backed by Terracotta — is strong.

    SCALABILITY

    People are asking questions about scalability. Quite frankly, I’m not worried about it.

    Scalability is a function of architecture. If you get it right, you can scale easily with new hardware. We got it right. I can say that with confidence because we’ve load tested the hell out of it. We put 1.3 million real world messages through our bus in a weekend. That may or may not be high throughput for you and your business, but I guarantee you it is for our’s.

    The messages we put through our bus take a fair amount of processing power. That means they take more time to produce their result than they do to route through our bus. How does that affect our server load? Terracotta sat idle most of the time. The box hosting TC is the beefiest one in our cluster. Two dual-core hyperthreaded procs, which look like 8 CPUs in htop. We figured we would need the most powerful server to host the brains of the bus. Turns out we were wrong, so we put some message consumers on the TC box, widening our cluster for greater throughput. Now the box is hard at work, but only because we put four message consumers on it.

    When we slam our bus with simple messages (e.g, messages that add 1+1), we see TC hard at work. The CPUs light up and the bus is running as fast as it can. 1+1 doesn’t carry much overhead. It’s the perfect test to stress the interlocking components of our bus. You can’t get any faster than 1+1 messages. But when we switched to real world messages, our consumers took all the time, their CPUs hit the ceiling, and our bus was largely idle. The whole bus, not just TC. We’ve got consumers that perform logging and callbacks and other sundry functions. All of these are mostly idle when our message consumers process real world workloads.

    We’ve got our test farm on 4 physical nodes, each running between 4 and 8 Java processes (our various consumers) for a total of 24 separate JVMs. All of these JVMs are consumers of queues, half of them are consumers of our main request queue that performs all the real work. The other half are web service endpoints, batch processors, loggers, callback consumers, etc. and each are redundant on different phsyical nodes. Because our message processing carries greater overhead than bussing, I know we can add dozens more consumers for greater throughput without unduly taxing Terracotta. If we hit a ceiling, we can very easily create another cluster and load balance between them. That’s how Google scales. They’ve got thousands of clusters in a data center. This is perfectly acceptable for our requirements. It may or may not be suitable for your’s.

    You might be thinking that dozens of nodes isn’t a massive cluster, but our database would beg to differ. Once we launch our messaging system and start processing with it, we’ll begin to adversely impact our database. Scaling out that tier (more cheaply than buying new RAC nodes) is coming next. I hope we can scale our database as cheaply and easily as our message bus. That’ll enable us to grow our bus to hundreds of processors.

    Like I said, I’m not worried about scaling our bus.

    HIGH AVAILABILITY

    I might not be worried about scalability, but I am worried about high availability. My company is currently migrating to two new data centers. One will be used for our production servers while the other is slated for User Acceptance Test and Disaster Recovery. That’s right, an entire data center for failover. High availability is very important for our business and any business bound by Service Level Agreements.

    Terracotta Server has an Active-Passive over Network solution for high availability. There is also a shared disk solution, but the network option fits our needs well. Our two data centers are connected by a big fat pipe, and Terracotta Server can have N number of passive servers. That means we can have a redundant server in our production data center and another one across the wire in our DR data center. We’ve also got a SAN that replicates disks between data centers. We might go with the shared disk solution if we find it performs better.

    Overall, though, it is more important for our business to get back online quickly than it is to perform at the nth degree of efficiency. Messaging, after all, doesn’t guarantee when your stuff gets run, just that it eventually runs. And if everything is asynchronous, then performance, too, is a secondary consideration to high availability.

    CONCLUSION

    If there’s one lesson to be learned through this blog article, it’s that one size does not fit all. Not all requirements are created equal. Our message bus is the right solution for our needs. Your mileage may vary. Some factors may outweigh others. For example, having a tight and tiny message bus that any developer can run in their IDE without a server (even without TC) is a great feature. No APIs lets us do that with Terracotta. You might have very different requirements than we do and find yourself with a very different solution.

    InfoQ writes about my use of Terracotta Server as a message bus

    Mar 6

    Posted by Mark Turansky in Architecture, Terracotta | No Comments

    Check out this article on InfoQ about using Terracotta Server as a message bus!

    HOW TO: Better JavaScript Templates

    Mar 5

    Posted by Mark Turansky in Code Hints, Engineering, HOW TO, Technology | 5 Comments

    JavaScript Templates (Jst) is a pure Javascript templating engine that runs in your browser using JSP-like syntax. If that doesn’t sound familiar, check out the live working example on this site and download the code. It’s Free Open Source Software.

    Better JavaScript Templates

    Who Saved Watt?!

    Mar 4

    Posted by Mark Turansky in Misc. | 2 Comments

    My family uses compact flourescent light bulbs. Our next cars will be hybrids. We’d love to go solar when the price per watt for the panels comes down, and I support net metering to allow people to reduce their monthly bills by putting energy back onto the grid . We recycle religiously. We’re green or at least we’re trying to be.

    So I made the Who Saved Watt?! site to a) encourage people to switch to CFs and learn other little conservation habits and b) add their saved watts to the aggregate total. I’d love to make the total interactive somehow, like a Google Map showing all the energy saved by locale. That’s for a future version.

    Here’s my eco-friendly merit badge:

    I saved
    1147.5
    watts!
    www.whosavedwatt.com

    Horses For Courses 2 (or Tools for Fools)

    Mar 1

    Posted by Mark Turansky in Engineering | 2 Comments

    My recent post “Linux is killing Solaris” is surpisingly controversial, if you could infer that by reading the comments on Reddit or watching the split vote on DZone.

    I think the critics and naysayers are missing a big point. One tool (htop on linux) is ridiculously easy to read at a glance while the other (prstat on solaris) requires parsing and mental math.

    You be the judge. Can you choose the right horse to run this course?

    Imagine you’ve got a dozen nodes on the network, each one hosting components of your enterprise message bus. You and your operations folks need visibility into the entire system so that you can tell at a glance whether something is going wrong or not.

    One tool is plain text, with row on row of process data, cpu utilization by process, etc. Want to know total CPU usage of the box? Add your processes together! “Well, process A is using 38%, process B is using 13%, and process C is using 4%. Let’s see, 38 + 13 + 4 is 55%. On to the next box!” Twelve console windows into all twelve nodes looking like this:

    htop_vs_prstat21.png

    Can you tell how much swap space your system is using by looking at this first tool? Nope!

    Alternatively, you can look at another tool that’s also plain text in a console, but has simple yet effective color-coded bars that display CPU and memory usage. It looks something like this:

    htop_vs_prstat1.png

    What’s important here is people. I don’t care if prstat runs twice as fast as htop. I don’t care if htop uses more memory or is less efficient. The fact is, they both run fast enough. What I want is for people to be fast when reading the console.

    Our Config Management team is going to have a single monitor with SSH shells open to all the nodes on the network. The monitor will sit in our Ops center and plenty of people will glance at it to see how our system is doing. If even one of them is doing math in their head to get CPU usage on a box, then I’ve failed the usability test. I picked the wrong horse for the course.

    So, htop runs on Linux and there’s no mention anywhere on the internet about it being unavailable for Solaris (except here on this blog). Get me used to all the niceties of Linux and I’m not a happy camper when I have to deploy my message bus to Solaris because my quick visual status bars are gone.

    This might seem like a trivial thing to get worked up about, but my responsibility as a leading architect at my company is to make things which are simple to run, easy to test, quick to report status, and to remain cognizant of the Ops and business folks that use our system to make money for our company. There’s still a ton of work to do after you’re code complete. Monitoring is one of those non-functional but critical requirements that has to be built in if you want a robust system.

    Solaris on x86 was too late. I could never afford Sun hardware at home or for development. So it all went Linux. And it’s not just for me, it’s for a lot of people. That’s why I wrote Linux is killing Solaris. I still think it’s an obvious point missed by no one, yet somehow it managed to stir up enough emotion in people on Reddit and Dzone.

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