Having recently implemented a database connection pooling in our web applications, I want to share some of the issues we stumbled upon during the implementation.

• Clean up your database calls Make sure that you close your ResultSet and the database connection after every call to the database or you risk to fill-up your connection pool with dozens of active unused connections. When working with only a single connection it’s easy to conveniently “forget” to close a ResultSet or a connection, so the next method can just re-use the same resource. In a pool, any connection could potentially be a newly allocated resource which you might have to initialize.
• Optimize and minimize your SQL calls Use specialized queries when appropriate. Make sure that you don’t initialize an entire object if you only need a handful of fields for a given function. Initializing an entire object might require a number of SQL calls, which can be minimized with a single specialized query. Avoid SQL calls that retrieve large lists of data, use limits whenever possible.
• Don’t expect a connection pool to solve all your database performance problems
  A connection pool is not a magic pill and is not always the best design decision. In most cases an application with well designed and optimized SQL calls will work just fine without a connection pool. In fact a database connection pools introduce their own operational limits (such as the maximum connections allowed) and add complexity to your application. On a positive side, implementing a connection pool will help you identify and expose any short falls in your exiting database design.
• Consider using existing open source database connection pool project Although implementing your own connection pool object is not rocket science, you should consider using an open source project if you can. Most open source connection projects will provide you with dozens of fine-tune settings to optimize your pool. When implementing your own pool, it will be difficult to consider all the settings that might be required to fine-tune your pool. Also most open source pool projects will provide you nice GUI widgets to show the status of the pool within your own application.
  We used Proxool http://proxool.sourceforge.net/index.html because of the comprehensive support for web applications built-in to Proxool.

• Don’t just assume that it works … Load Test! Once your pool is implemented, make sure that you test your application under a heavy load. Watch how your pool behaves and try to determine some benchmarks. Excessive number of active connections in your pool during load testing will tell you that you need to improve your SQL calls. Make sure that the number of active connections returns to the minimum after each load test.

In conclusion, database connection pool can be useful in some applications but should not be treated as a must have requirement in every situation. Just like any other feature in your application, implementing a database connection pool should be approached with a proper design and implementation plan.

Tags: connection, database, pool, sql

Happy Holidays from Unlimi-Tech!

Leading into the holidays and the New Year, we wanted to send out a note to all of our customers to thank them for their patronage, and to briefly recap 2009.

In this past year we have continued innovate and grow. We experienced record growth this year, in terms of worldwide adoption of our FileCatalyst software and also in terms of increasing staff to develop groundbreaking features and provide our clients with the same level of personalized and expert support that they are accustomed to. We are poised to continue this growth into 2010. Much of the credit goes to the hard work and determination by our staff; however, nothing would be possible without our growing base of loyal customers.

As with any business, we owe everything to our clients. We feel that this is particularly true in software development, because it goes beyond sales. Having strong relationships with customers who are eager to share their observations and suggestions leads to improvements in our products that might not otherwise be in place! When the creativity and enthusiasm of your customer base matches with that of your employees, great things can happen.

Throughout 2009, we released several major new features including full official release of our SDK, the first iteration of our Outlook Plugin, and cloud deployment through our Amazon AMIs. Under the hood, we have continued to boost performance of the FileCatalyst core, reaching multiple Gbps speeds even with high latency and packet loss. We have added almost 100 new features to our client and server applications, almost all in direct response to customer feedback.

We continue to receive wonderful (and much appreciated) comments on our technical and pre-sales support as well. Our staff is really just doing what seems natural: providing answers in a friendly and clear way, being available for honest-to-goodness phone conversations and web meetings, and being dedicated to finding the answers if they’re not immediately obvious. We’ve come to take it as a real point of pride that our customers consider our support to be above and beyond what they have come to expect from other companies. So a big thank you to everyone who is so thoughtful and encouraging when providing those kinds of comments– it fuels us to work even harder for you!

On behalf of everyone here at Unlimi-Tech, Happy Holidays! We are look forward to continuing to serve you in 2010!

Here are some pictures from the JavaOne conference.

…enjoy.

Well, two days have passed since NAB closed for exhibition, and I can say that I enjoyed the whole experience. Unlike some of the other staff who attended, this was my first trade show, and what a trade show to attend! We’ll file a full report sometime in the coming week, but for now here are a few isolated and random thoughts from a personal rather than corporate perspective:

• My first sight of the inside of the show was the entrance to the South Hall. Glowing signs from an assortment of incredible exhibitors with amazing products, and I knew that anybody attending the show would certainly find something of interest. Mesmerizing!
• If you’re a generally outgoing person as an exhibitor, any nerves fly out the window as soon as you talk to your first interested attendee. When you’re enthusiastic about your own product (as I am), and the attendee is genuinely interested (as anybody stopping for more than a few seconds was!), the conversation is exciting and easy for both parties
• You’re still there for business. Have fun (it was Vegas after all!) but be sure that you keep your head “in the game”; only one morning was a wee bit rougher for me than I would have hoped for, and it was a lesson very quickly learned.
• Having a prime location is great, but having a great product is even better–people will seek you out when you have something compelling to offer
• Flying the red-eye is no fun. (I had to come back early for a previous engagement)

There’s a lot more to share, but the bottom line is that we had a great show, met some fantastic people (whether they were looking for a file transfer solution or not), and had some great non-tradeshow moments in Vegas as well (excellent and varied food). As a first trade show experience for me, I don’t think it could have been any better.

Greg

If you’re into podcasts and Massively Online (MMO) gaming, there really is no better place to go to than VirginWorlds. Yes, I am a bit biased with this because, I too, have a show that I do there as well ….one among the many show offerings at that site.

For those that are not familiar, the flagship podcast covers all of the news and technology trends that is happening within the MMO gaming space. Recently, VirginWorlds podcast host Brent, sat down with FileCatalyst CEO Chris Bailey at GDC 2009 to talk about the FileCatalyst product and how it fits within the gaming industry.

Go take a listen here. I encourage you all to listen to the whole podcast…but if you just want to hear Chris, his interview starts at 57:47-ish.

Enjoy.