That Puerto Rican Rubyist

Now that I live on the West Coast, I’ve been able to attend many of the wonderful tech conferences that are hosted in the Bay Area. Yesterday, I attended MongoSF in beautiful San Francisco. I’ve been using MongoDB for a while now, mostly for personal projects. I’ve written some projects on GitHub that uses MongoDB as the primary data store, and I have also migrated some existing MySQL tables in other projects to use MongoDB instead. Having read MongoDB: The Definitive Guide from front to back, and spending quite some time on the MongoDB docs, I feel like I have a good grasp on the tool. So I was pretty excited to go to this conference and discover some more things about my one of favorite pieces of tech.

There were multiple tracks in this conference, and unfortunately I still can’t clone myself in this day and age, so I’ll just briefly touch on those sessions that I was able to attend.

Monitoring & Queuing MongoDB: This talk, given by David Mytton from Server Density touched on some of the integrated monitoring tools and commands that MongoDB has baked in. He also showed a bit of Server Density’s MongoDB monitoring system, which looks to be incredibly useful. Overall, the talk was decent, but anyone who has MongoDB running in production should know most of this stuff already.

Evolving from relational to document store: Graham Tackley, lead for the web development team over at the U.K.’s Guardian news site, gave an interesting talk on how the site has evolved over time since the mid-90s (Lots of Perl / CGI goodness). Currently they are in the process of moving certain parts of the site to use MongoDB. Besides the history lesson on the site, he also mentioned how they are dealing with possible future changes in architecture, notably by building APIs around the site functionality. This talk got my gears running about some of my own projects, and how I might build any new projects I have in my mind.

MongoDB Profiling and Tuning: This talk was given by Kenny Gorman, who works as a data architect at Shutterfly. Kenny went through some of the steps used to profile MongoDB, like using explain() on your queries, and how to make things faster, not only on the software side, but also on hardware. He brought up Facebook’s Flashcache, and how it makes MongoDB speed up. I particularly enjoyed hearing the hardware side of things, as I feel like hardware is mostly overlooked by developers.

MongoDB’s New Aggregation Features – A Sneak Peek: Chris Westin is a core MongoDB contributor, and he gave us a sneak peek at a new framework for aggregating records in MongoDB. This framework is really not meant to replace Map/Reduce, which will still serve very well for massive data. But for people like me, who need to aggregate smaller amounts of data (thousands of documents instead of millions), this will be much easier and faster to deal with. Very cool stuff, and I can’t wait to use it.

Lessons Learned from Migrating 2+ Billion Documents at Craigslist: Former Yahoo! and current Craigslist employee Jeremy Zawodny spoke about how Craigslist is using MongoDB for their posting archive, and the lessons learned along the way, like the usage of replica sets even in development, document encoding, and how important data types are when migrating collections. He had a similar talk at MongoSV a few months ago, so I didn’t feel like there wasn’t much new information here. Still, a good talk about migrating a large amount of data from MySQL to MongoDB – it can be done.

Practical Scaling and Sharding: Eliot Horowitz is one of the main MongoDB contributors, and the CTO of the company that backs MongoDB, 10gen. He went through the features and usage of Replica Sets and Sharding, with a few use cases and live examples. This seemed more like an introductory talk more than anything else, so there was nothing groundbreaking here.

MongoDB at Foursquare: This talk was given by Jorge Ortiz, an engineer at Foursquare, who proceeded to mention briefly how MongoDB was being used at Foursquare, some of the lessons they’ve learned throughout the years with MongoDB, and talked about their Scala library for querying MongoDB called Rogue. Frankly, I was disappointed with this talk, as Jorge didn’t give much insight outside of a few numbers and oft-repeated tips. I was expecting a more informative talk here.

Indexing & Query Optimization: Alvin Richards, a West Coast 10gen employee, gave an in-depth talk about indexes in MongoDB. He went through everything, from basic indexes, to indexing order, to new indexing options in MongoDB 1.8 (sparse indexes and covered indexes), to even showing representations of the internal B-Tree implementation. Very informative.

Lightning Talks: This was divided in three shorter talks. First up was Michael Goff, who spoke about how his company, Cocoafish uses MongoDB to serve up data to mobile apps. Next was Chris Carrier (Is he on Twitter? I couldn’t find an account to link here) from Zuberance, speaking about how to create a reporting backend using MongoDB. Last, but not least, was Chad Arimura, who went through SimpleWorker, a cloud-based job scheduling service that uses MongoDB. These talks were short – which you might have figured out with ‘Lightning’ in the title – and seemed to be mostly about the speakers’ particular sites more than anything else.

At the end, Eliot Horowitz gave a quick rundown on the upcoming features for MongoDB 2.0, like TTL collections, online data compaction, faster Map/Reduce, etc. Surprisingly, this 2.0 release is scheduled for June 2011, as in next month. Seems like they’re going to be doing quicker iterations and getting new stuff out there as soon as possible, which can only lead to good stuff for users. There was an after-party, but when I swung by the place there was a massive line outside to get in, so I decided to head home instead. Unfortunately, this is the third time in as many conference after-parties that I’ve had to do this, so it seems like these after-parties don’t scale well.

Overall, while the conference was pretty good, and everything was organized very well, most of the times I felt like I was out of place or at the wrong talk. Judging from the few people I spoke to, and those that I overheard, it seems like most people at the conference hadn’t used MongoDB much (or at all), and many talked I went to touched on what I consider some of the basics of MongoDB. Even if they weren’t basic topics, like Replica Sets or Sharding, if you have read a recent MongoDB book, you knew what most of the speakers were talking about. Also, there was plenty of repeating of the same tips over and over again in a lot of the talks. For example, in the nine talks I went to, the speaker mentioned the “always keep indexes in memory” rule of thumb in at least five of those talks. Truth be told, MongoDB isn’t really a super-deep technology (even the aforementioned O’Reilly book clocks in at a bit north of 200 pages), so this can be the reason why. But I wanted to know more on the upcoming features in MongoDB (I only really saw one talk in the schedule like this, which was the new aggregation framework), and some more in-depth views of how companies are leveraging MongoDB in their technology stack instead of just pointing out how awesome MongoDB is – which we already know.

In any case, I had tons of fun, learned some new tips and tricks, and got some fresh inspiration to use in my own work soon. The best thing about these conferences is knowing that what you’re learning and using is valuable not just to you, but to many out there, and it just gives you motivation to keep on using those tools in familiar and new ways. Much props go out to 10gen for making this conference go smoothly, and hopefully there’s another one of these sometime next year.

Last week, I was doing some routine maintenance on my VPS (which I should definitely do more often, as well as writing some more blog posts) and I noticed that one of my cron jobs that backed up some files to Tarsnap was incorrect and silently failing. Now, I could modify this simple Bash script to shoot off an email to me whenever something happens. But I was feeling a bit creative and didn’t want to just write a few lines of Bash and be done with it.

As any software engineer is prone to do, I wanted to build something a bit more cool. That’s when I figured out that this would be the perfect chance to finally do something useful with Notifo. Notifo is an awesome service that provides real-time notifications to a number of devices, in particular to iPhones (although their list of supported devices seems to be rapidly expanding). I’ve been using Notifo just for setting up simple timed reminders and to get notified of replies and mentions from Twitter using push.ly. Getting notifications in real-time of failures would be something great to have.

Using Ruby,, Sinatra and the Notifo gem, I quickly whipped up a small app called Fail Notifier. Basically it’s a service where any application / server can make a simple HTTP POST to where Fail Notifier is running, and it will relay the message to the user in real-time using Notifo. Simple, but very useful. The best thing is that you can use it anywhere to notify you about anything from any app, programming language, server, or anything else that can make a simple HTTP request. For example, I have Fail Notifier installed on my VPS (nginx and the recently-released cURL about some failures, and I also have some notifications for very important background tasks in a Rails app.

Of course, Fail Notifier is entirely open-source for you to do with it as you please. Feel free to fork the code on Github and hack away to your hearts content.

It’s been a few months since my last post around these parts. I’ve mostly been keeping busy with fitting into the whole West Coast lifestyle and, of course, busy at the job. Although I do miss New York City from time to time, particularly while watching older episodes of How I Met Your Mother, I’ve really enjoyed my time in the Bay Area. People here are interesting, and tech is such a huge part of the culture. It’s been a fun ride.

This post, however, is not about the adventures of a Puerto Rican being thousands of miles from home (although it could certainly make for an interesting story for another day). This post is about me pulling the trigger on something I’ve wanted to do for a long time – switch my VPS (which is where this very blog is running) from Slicehost to Linode.

To begin, I wanted to state that Slicehost is very, very awesome. I’ve been a customer of theirs for more than two years, and never had any major issues with them. With the exception of some outages, their service ran smoothly for the most part. This is more than anyone can ask for. So, if Slicehost is so awesome, why didn’t I marry them? I was perfectly content in staying with them.

However, as I was experimenting more and more with Ruby, Rails, Python and other languages / frameworks, my VPS – which was the smallest slice available at 256 MB – was obviously starting to suffer under the memory constraints. Since these were mostly experiments, I didn’t want to splurge and pay almost double for a 512 MB slice. That’s when Linode announced that they would be increasing the RAM sizes of all their slices. So it was either to stay with Slicehost and have my VPS struggle to keep up with my experiments (or pay more per month), or switch VPS providers. After reading all around the Internet about how good Linode was, I decided to go for it.

I opened an account with Linode and instantly had my sparkling new VPS running. I transferred all my files from the old Slicehost VPS and just had to point my domain names to the new Linode VPS. My main concern initially was that Slicehost had really spoiled me with their control panel, especially for DNS management. It was what had initially drawn me into their service to begin with, so leaving that behind was a bit scary. Thankfully, Linode has their own control panel that’s equally great to use. I was able to configure and point my domain names to the Linode VPS, and had everything working quickly.

As far as performance, I had been reading for years how Linode has faster I/O performance than Slicehost. Turns out that those tests seem to be true – The VPS as a whole feels much snappier, from logging in via SSH to serving up this very blog.

One of the major issues people had against Linode in the past was that they lacked any integrated backup system, a la Slicehost. They actually introduced backups a few months ago. This wasn’t a major concern for me (I’m using Tarsnap, which deserves a blog post of its own), but for those who need this sort of service, know that they have you covered.

Like I mentioned, Slicehost is great, and I wouldn’t encourage people to not use their services. I just had different needs that Linode seems to be handling as well as I expected. It’s only been a couple of days, but I think I’ll be shutting down my Slicehost VPS for good.

After two years, yesterday was my final day of being a developer for BarterQuest. As anyone living in expensive New York City in the same situation, I have been focusing part of my energy looking for a new gig. I’m pretty confident, despite the current economy, that I will land on my feet sooner rather than later. I have a few leads, with one in particular that I am really hoping will come through.

In the meantime, I’m not just throwing my resumé in the face of companies everywhere in the U.S. I have also decided that since now that I have quite a few extra hours in my days, I should really do productive things instead of sitting on my couch and re-watching all previous seasons of 24 (believe me, I would watch all 7 seasons in a row if I could) or jamming away to Guitar Hero. This is a perfect chance to do lots of technical things I’ve been wanting to do for months, but just never got the time to do so. Here’s a short list of some goals I’d like to get started on.

Learning new stuff

For the past two years, I’ve been exclusively using Ruby and Ruby on Rails at my day job. I’ve always wanted to broaden my skills by doing other types of programming, but when you take into consideration that I would usually be at work more between 9-10 hours per day, plus a commute that would sap an additional two hours, there wasn’t much time for me to be able to do personal things, let along learn new stuff. Now that I’m finally free, I can now spend more time with those things I’ve wanted to experiment with.

I’ve always wanted to learn iPhone application development. I know the basics of Objective-C, and have the book iPhone SDK Development by Bill Dudney, but I was never able to sit down and code something up. I have a few ideas for apps, so even if I can make a simple app that’s accepted to Apple’s App Store will be an achievement for me.

I’ve been very interested in implementing Push technology to web apps, like Comet or Web Sockets, using nginx’s Push Module and Orbited.

Although I’ve never had the opportunity to work with extremely large data sets, I’ve always been curious about frameworks like Google’s MapReduce and Apache Hadoop, particularly how well they can “crunch” the data thrown at them.

Keep on with what I already know

As I mentioned, I’ve been using Ruby for years now, and I know Ruby on Rails and Sinatra pretty well. However, just because I want to learn new things doesn’t mean that I want to abandon this awesome language. In fact, I want to keep using it more with the latest toys.

Thanks to Ruby Version Manager, I was able to safely install the latest versions of Ruby 1.9 and MacRuby and start learning their new features. I was also able to check any possible compatibility issues in my older applications with different major Ruby versions. Seriously, if you are a Ruby developer using a Mac or Linux, install RVM now if you haven’t.

Recently, there have been more and more news about Ruby on Rails 3, the next major release for the wonderful framework. I’d like to stay one step ahead of the pack and start learning about the new changes before it officially hits the web. One of the leaders of the newest Rails changes, Yahuda Katz, has written lots of blog posts relating to the changes in Rails 3. They’re definitely worth a read.

Strengthening my shortcomings

There are quite a few things – development-wise – that have been bugging me for a long time, yet I’ve never taken the proper steps to correct. Now is as good a time as any to take on these things and finally conquer them.

My main weakness, as a web developer, is that I’m pretty bad at design. I know CSS and its properties, I know about browser incompatibilities (having been a victim many times before by the evil and immortal Internet Explorer 6 browser) and all that stuff. But as far as design goes, like font sizes, element placement, usability and colors, these things are not my strong suit. I’ve actually stocked up on some books about these subjects (like Don’t Make Me Think by Steve Krug and Web Design for Developers by Brian Hogan), so I hope that by the time my unemployment ends, I’ll be much better off making my work look good – or at least decent.

Another weakness I consider is that I get distracted from development from time to time. It’s not frequent enough to affect the quality of my work, but it’s enough to annoy me when I do it subconsciously and I then catch myself in the act. I have read some people who had some success using the Pomodoro technique, so starting tomorrow I decided that I’ll give it a try. There’s a nice little app called Concentrate for the Mac that seems to be just the thing I need during those times when I need to get stuff done and not get distracted.

Beef up my GitHub profile

I have to admit that I’m a little bit ashamed to see my GitHub profile virtually empty. For a long time, I’ve been wanting to add more of the projects that I have in my laptop to GitHub and see if some of them take a life of their own. Sadly, for whatever reason, I haven’t done that. Most of the times I’m a bit too critical at my code and think it’s embarrassing to make public, but that’s really what I need to do to get better as a developer. I can take criticism with the best of them, so there’s really no excuse. I need to make more of my code open-source, period.

Not only do I want to show my own work, I also want to give back to the community. I have used so many open-source projects over the years, yet I’ve only submitted a handful of patches to very few projects. I don’t want to be a person who takes, takes, takes and never gives anything back in return. So I’m going to take steps to correct that. I’ve started cloning some repositories of my favorite projects from GitHub to my computer to start reading their code more in-depth, which I had been doing anyway. I’ll check if these projects have Lighthouse pages with open tickets, or if there are any open issues on their GitHub page. A few years ago, Dr. Nic wrote an excellent post titled “8 steps for fixing other people’s code” that inspired me to start finding features or defects that I can handle.

I have to say, I’m only one day into this routine, and I don’t remember the last time I felt this free and liberated doing what I wanted to do. Full-time employment is great for earning money and making substantial stuff, but sometimes there’s a feeling of emptiness due to not being able to explore on your own. Being unemployed doesn’t mean that you need to spend all your time looking for work. Unless you’re truly struggling economically and can’t pay the bills in the next couple of weeks or even days, why not spend part of your time gearing up for the future?

As many other developers, I’ve been experimenting with the different “NoSQL” data stores. Most of them are really great, like Redis, Tokyo Cabinet and CouchDB. My favorite so far, however, is MongoDB. I think it hits the sweet spot between a normal relational databases and key-value stores. After a while playing around MongoDB, I decided to do something with it. That something that I did is called MongoShort.

MongoShort is a very simple URL shortening service, written with Sinatra and MongoDB. I originally wrote this little app to be used as part of a larger Rails application. However, it was mostly done as a way to do something with MongoDB. Particularly, I wanted to start using the awesome MongoMapper library. It’s really a breeze to use all these tools together, and it makes developing small apps on Ruby really fun. I hope someone can grab a copy of MongoShort and learn a bit of the basics of these wonderful tools.

Go fork MongoShort on GitHub now!

In my development blog, I previously wrote that MongoDB was the future of database storage. I might reconsider my decision, now that I’ve discovered Redis. In a nutshell, Redis is a key-value store. But it’s not a simple key-value database, as it has lots of commands and extra goodies, such as file persistence (so data can be stored from memory to a file, and restored in case of failure) and awesome data structures like lists (with push / pop) and sets (even ordered sets). Besides that, Redis boasts atomicity and even master-slave replication. It’s quite a lot of stuff for a lean package.

One of the things I love the most about Redis is it’s speed. Believe me, this little database is fast. Redis includes a benchmark tool, so I ran the default benchmark (Approximately 10,000 total requests per command, from 50 simultaneous clients) just to demonstrate its raw speed. These tests were run on a Mac Mini (1.83 GHz Intel Core 2 Duo, 2 GB RAM) under Ubuntu 9.10 Server:


dennmart@ubuntu:~$ redis-benchmark
====== SET ======
10005 requests completed in 0.14 seconds
50 parallel clients
3 bytes payload
keep alive: 1

34.89% <= 0 milliseconds
99.19% <= 1 milliseconds
100.00% <= 2 milliseconds
74111.11 requests per second

====== GET ======
10003 requests completed in 0.13 seconds
50 parallel clients
3 bytes payload
keep alive: 1

34.62% <= 0 milliseconds
99.79% <= 1 milliseconds
99.83% <= 2 milliseconds
99.87% <= 3 milliseconds
99.91% <= 4 milliseconds
99.94% <= 5 milliseconds
99.97% <= 6 milliseconds
99.99% <= 7 milliseconds
100.00% <= 8 milliseconds
74649.25 requests per second

====== INCR ======
10005 requests completed in 0.15 seconds
50 parallel clients
3 bytes payload
keep alive: 1

25.60% <= 0 milliseconds
99.73% <= 1 milliseconds
99.80% <= 2 milliseconds
99.83% <= 3 milliseconds
99.86% <= 4 milliseconds
99.89% <= 5 milliseconds
99.92% <= 6 milliseconds
99.95% <= 7 milliseconds
99.97% <= 8 milliseconds
100.00% <= 9 milliseconds
65392.16 requests per second

====== LPUSH ======
10001 requests completed in 0.13 seconds
50 parallel clients
3 bytes payload
keep alive: 1

37.62% <= 0 milliseconds
99.78% <= 1 milliseconds
99.82% <= 2 milliseconds
99.86% <= 3 milliseconds
99.89% <= 4 milliseconds
99.93% <= 5 milliseconds
99.96% <= 6 milliseconds
99.99% <= 7 milliseconds
100.00% <= 8 milliseconds
77527.13 requests per second

====== LPOP ======
10000 requests completed in 0.14 seconds
50 parallel clients
3 bytes payload
keep alive: 1

34.13% <= 0 milliseconds
99.69% <= 1 milliseconds
99.82% <= 2 milliseconds
99.86% <= 3 milliseconds
99.90% <= 4 milliseconds
99.93% <= 5 milliseconds
99.96% <= 6 milliseconds
99.98% <= 7 milliseconds
100.00% <= 8 milliseconds
74074.07 requests per second

====== PING ======
10000 requests completed in 0.12 seconds
50 parallel clients
3 bytes payload
keep alive: 1

43.79% <= 0 milliseconds
99.80% <= 1 milliseconds
99.85% <= 2 milliseconds
99.89% <= 3 milliseconds
99.91% <= 4 milliseconds
99.93% <= 5 milliseconds
99.97% <= 6 milliseconds
100.00% <= 7 milliseconds
86206.90 requests per second


Yeah, you read that right. On this somewhat low-end computer (by today's standards), Redis still manages to do over 74,000 SET (write) and GET (read) operations per second. Push and pop list operations also do well over 70,000 requests. On bigger hardware, expect these numbers to be much higher. Besides speed, I've also been impressed by the stability of Redis. I've been running Redis non-stop on the Mac Mini for over two weeks, and I've never had a single issue with it.

I got really interested in Redis after Defunkt (of GitHub fame) open-sourced Hurl. Hurl was an entry in this year's Rails Rumble competition. I used it quite extensively when developing with PayPal's APIs. After it was released, I noticed that Hurl used Redis for persistence. I was kind of puzzled why a key-store value was used for this. However, Defunkt wrote an excellent post mostly explaining the SORT operation, but also included some additional details on how Redis was used in Hurl. It made the decision to use Redis clear. Well, I'm also willing to bet that he used Redis because us programmers love to use the new hotness.

I feel that Redis will be something big soon. There are a few open-source projects using it, including the aforementioned Hurl and Resque. I already have a few ideas where I can use some of this functionality for current sites that I'm working on (such as simple counters, or a tag-like system where we can push and pop tags from a list). Check Redis out if you need some quick and simple storage.

Ever since I bought my MacBook Pro a few months ago, my poor ol’ Mac Mini has been alone and lonely. I really didn’t have much use for it, since I transferred all important work files to my new laptop. So what would I do with it? That’s when Ubuntu 9.04 was released. Back when I was in Puerto Rico, I would always get excited when a new release of my favorite Linux distributions (Fedora, Debian, Slackware and Ubuntu) was announced. It had been a while since I gave one of these new releases a test drive. It would also give me a chance to use my Mac Mini as a server, where I can test some new software that I’ve been wanting to check out for a while.

The Mac Mini seems like a good, cheap alternative for a server if you have one lying around unused. These machines are pretty quiet, consume low amounts of energy and are fast enough for most server tasks. Here were the steps I took to get a fully-functional Ubuntu Server installation on my Mac Mini. As a side-note, my Mac Mini is a Mac Mini Core 2 (1.83 GHz) with 1 GB of RAM and an 80 GB hard drive.

1) Download the Ubuntu Server disc image and burn it to a CD. I chose downloading via BitTorrent. Also, I downloaded the 64-bit version (torrent filename: ubuntu-9.04-server-amd64.iso.torrent), although the 32-bit version should work just fine. Make sure you seed for a while after you download your disc image!

2) You will need to partition your Mac Mini hard drive, to create some space for the Ubuntu installation. If your Mac Mini has Mac OS X 10.5 (Leopard), you can use the Boot Camp Assistant to create a partition. Unfortunately, you won’t be able to use Boot Camp if your Mac Mini is running Mac OS X 10.4 or an older version. When starting the Boot Camp Assistant, you will be asked to specify the size for your new partition. You’ll need at least 10 GB of free space in your hard drive to do this. Depending on how much hard drive space you have available, create a partition. Once completed, the Boot Camp Assistant will ask if you would like to restart to begin installing your new operating system. Don’t do this just yet. Quit the Boot Camp Assistant.

Note: I was having problems creating a partition, even though I had plenty of free space on my hard drive. The reason was because my hard drive was apparently too fragmented, and there were some files that couldn’t be moved to create the new partition. Since I have a 500 GB external drive and use Time Machine to back everything up, I decided it would be best to just do a clean install of Mac OS X 10.5. Once Leopard was installed, I created the new partition using Boot Camp Assistant without any problems.

3) Before restarting your Mac Mini, you will need to install a boot manager called rEFIt. rEFIt will help install Ubuntu easily, and makes selecting between Mac OS X and Linux after installation a breeze. To install rEFIt, download the Mac disk image (.dmg) file. Once the image is mounted, install the boot manager by executing the rEFIt.mpkg file. After installation, to make sure the boot manager was properly installed, there should be a directory named /efi in the root directory of your system. Open the Terminal application on your Mac Mini, and execute the following commands to properly install the boot manager (You will be prompted for your password):


cd /efi/refit
./enable-always.sh


4) After rEFIt is installed, insert the Ubuntu Server CD you created and restart your Mac Mini. When rebooting, you’ll immediately notice the rEFIt boot manager screen. This boot manager should recognize the Ubuntu Server CD (marking it with the ubiquitous Linux penguin logo). Select this option, and the Ubuntu installation process should begin.

5) Installing Ubuntu is beyond the scope of this post, but it’s pretty easy to install if you have never done it before. Don’t be intimidated by the command-line look of the installation process! Just following the instructions and everything should be installed in no time. There were a few things I had to do differently in my case:

• When the Ubuntu partitioner starts, it will show all available partitions in the hard drive, including the partition for Mac OS X. You’ll recognize the difference between the Mac OS X partition and the one you created using the Boot Camp Assistant by looking at the format of the partition (Mac OS X uses the HFS format, while the one you created is using the FAT32 format). Since I wanted to use a different format for this partition (ext3), I selected the FAT32 partition and deleted it. Once deleted, you’ll see ‘Free Space’ where your partition used to be. Select the free space, and the partitioner should ask if you want to let it create the necessary partitions. This is the easiest way to set up your new partition for Ubuntu.
• After installing the operating system, the Ubuntu installer will ask where you want to install its boot manager, GRUB. Since we don’t want to over-write rEFIt that’s install on the drive’s Master Boot Record, we need to install the GRUB boot manager in the boot record of the new partition. So where the installer prompts you to write the location where GRUB should be installed, write hd(0,2), which is the location of the new partition (provided you only have the Mac OS X partition and the new Linux partition).

6) If everything went smoothly, your Mac Mini will eject the CD and reboot. rEFIt will be on display once again, this time letting you choose to boot Mac OS X or Linux. Select Linux, and after all of Ubuntu’s processes start, you’ll be presented with a prompt. Congratulations, you have Ubuntu 9.04 installed in your Mac Mini!

I’m sure that installing any other Linux distribution will be more or less the same. Keep in mind that since I installed the server edition of Ubuntu (command-line only), I have no idea if video, sound, wireless connectivity (I connected my Mac Mini to my router using a Cat-6 cable) or other things will work properly in a Mac Mini. I’m sure the Ubuntu community (and the Linux community in general) have solved most common issues by now. If I install a different Linux distribution using a GUI, I’ll write about it and let everybody know.

It’s been quite a while since I last updated this blog. I should seriously start writing more often. So, what have I been up to? With the cold weather here in New York City, it gets difficult sometimes to go out and have fun in the city. As usual, most of my time is spent on technology, software development, stuff like that. Here’s a brief recap of what I’ve been working on:

Got a new MacBook Pro, and I love it – I finally gave in and bought myself a shiny new MacBook Pro. I’m having a blast with it. For the open-source developer in me, this has everything I could ever want. It’s a beautiful and sleek machine that has gotten me highly motivated to start expanding my knowledge in different directions. While I still consider these laptops to be pricey, they’re really great.

Learning Objective-C for Mac and iPhone development – Since I got a nice Mac, I figured I should start learning Objective-C, then eventually get into Cocoa and the iPhone SDK. I’ve always been impressed by some nicely-done open-source Mac applications, and iPhone apps have always seemed to be so creative, so I wanted to learn how to build some myself. Since I’ve been working for so many years on dynamically typed languages (like PHP and Ruby), it’s kind of a total change of pace to go back to a somewhat-statically typed language like Objective-C. It’s been a bit of a challenge, since I last used a C-based language back in my college days. But it’s going along well so far.

I’ve compiled quite a few resources for learning all of these things. I recently purchased a book called Programming In Objective-C, which seems like the de-facto book on Objective-C, as it’s pretty extensive..And there are a few good screencasts – PeepCode developed a screencast dubbed Objective-C for Rubyists, and The Pragmatic Programmers have a screencast series by Bill Dudney called Coding in Objective-C. Of course, Apple has done a fine job with their Objective-C documentation. All of these resources should get you coding in Objective-C in no time.

The iPhone development part is mostly being learned because at my day job we would like to create a nice iPhone app for users of our site. I truly think that a mobile interface will expand our user base easily, even if people say they don’t really use mobile interfaces for a lot of things. I find myself using Facebook and Amazon’s iPhone apps more than I visit their sites.

BarterQuest is getting better and better – It’s been a wild ride on BarterQuest since we launched. We’ve been featured all over the place, from blogs to television shows, and we’re getting more and more users visiting, registering and trading on our site every single day. I’ve even traded twice already, and everything has gone as smoothly as it possibly could. It’s a great way to get the stuff you want by getting rid of the stuff you don’t want.

If you haven’t checked out our site yet, or haven’t done so in a while, I highly recommend you visit us soon. We’re going to be adding support for Real Estate in a few weeks, so our range of tradable items will greatly expand. And stay up to date with all that we’re doing by following us on Twitter.

Learning (and liking) CouchDB – My curiosity with CouchDB started when people were mentioning it quite a bit, and some Rails libraries like CouchRest were gaining some attention. So I checked it out for the first time, and I had no freakin’ clue why someone would use document-oriented databases, when relational databases did just fine.

Then a week I was working on a side project, and when trying to design my classes, I noticed that I would either have to denormalize my database tables, or be strict with normalization, but have a rather messy database schema. Then it just hit me – I finally knew the reason why CouchDB would rock in this scenario, where the data I was storing wouldn’t always follow the same structure. So I got into it, and I’m really liking it a whole lot. It’s something different, yet really useful in some situations. Seeing that there’s a market for databases like these, like Amazon SimpleDB, it seems like CouchDB (and document-oriented databases in general) will gain much popularity in the foreseeable future.

These are just a few things I’m playing along with. It seems like there are a lot of fun times ahead in software development and computing in general. I’m just happy to be able to ride the wave.

I just stumbled upon a script that MySQL includes nowadays called mysql_secure_installation. It runs a series of steps to remove some of the default installation options that MySQL installs, like an anonymous user and a test database. When you run the script, it does for the following:

• Prompts you to change your MySQL root password, especially if you haven’t set a root password yet.
• Removes anonymous access to your database server.
• Restricts root access to localhost only.
• Drops the ‘test’ table that’s installed automatically.
• Flushes the privileges so that all changes are taken immediately without having to restart the database server.

Here’s the output when running the mysql_secure_installation in one of my servers.

In all, it’s something that I’ve been doing manually for a while. And I bet that there are many, many developers out there who, even on production servers, don’t even bother to remove these things. Obviously, this isn’t the “be-all and end-all” of MySQL security, but it’s a big step away from the default installation. Go run this script now! Well, unless you’re a security expert who already did this, either manually or with the script. If so, then I salute you.

I posted this story on a non-technical message board I frequently visit, as a service for some of the users there who might not have a clue on how easy it is to retrieve data from a supposedly-formatted drive. I decided to pass it along here as well. I think privacy is very important, and with the proliferation of electronic devices that store data, it’s getting easier to retrieve information from others.

Here’s a story of some dumb-ass kids who recorded themselves smoking weed on a digital camcorder, returned the camcorder to the store, forgot to erase their tapings (most likely due to said kids smoking weed previously) and the next person who bought the open-box camera from the story posted the videos all over the Internet for all the world to see:

Remember to delete your stuff from electronic equipment if you’re returning it, selling it or giving it away. And even then, be wary of it.

I was once sold a USB flash drive from a friend, and although my buddy deleted the contents, I was able to see what he had their previously before with a freely-available program off the Internet (don’t remember exactly which one right now), out of curiosity. Dude had some… let’s say ‘interesting’ pics of his then-girlfriend.

His way of deleting the contents was to simply do a quick format on the drive from his Windows machine before giving it to me. To avoid all the technical details, for those who don’t know, what this does is simply destroy the FAT table and/or boot sector, which is a sort of ‘table of contents’ for the drive, thus nothing appears when you try to access the drive. But the data is still in the drive’s sectors, and unless you rewrite those sectors (either by copying something new in the flash drive or using some software, which I’ll get to in a minute), they’re easily accessible.

The program I’ve used for a while with Windows is called Eraser (I carry a portable version of this program on my USB drive, called Eraser Portable), which makes sure your data is clear from your portable device (like flash drives, SD cards for digital cameras, even iPods). In short, what this does is over-write the sectors on the drive multiple times with ‘garbage’, so it’ll be virtually impossible to get that information from freely-available tools. I’m guessing the government has more advanced tools, so for the overtly paranoid, you’d be better off just smashing the drive to pieces and dipping them in a vat of acid.

Just wanted to pass this info along so you people can keep your privacy, and know how easy it is to grab a hold of your data.