There is a growing trend of open source-based applications running mainstream business-critical applications. Part of this is due to the availability of new solutions software that, when added to the open source application stack, greatly expands the overall reliability and scalability of the resulting applications, allowing them to be "enterprise class."
TCO. That simple three-letter acronym is widely used and also widely misused. It's not the initial key driver for critical business purchases even if some vendors would like you to think that it is.
Let's consider the issue in more detail. Linux is often cited as a lower-cost alternative to proprietary systems. The lower TCO is a result of lower software licensing costs combined with commoditized and inexpensive hardware. But there's more to TCO than that.
You are a manager who needs to evaluate and purchase the needed software components to build and run a credit card billing system. This system is the heart of your business. If it's down, your business is down. If there are transaction bottlenecks - or worse, lost transactions - your customers are not happy, to say the least, and your manager won't be either. Imagine explaining to an irate customer that his or her problem is because you opted for the lowest TCO solution. I wouldn't want to be handling that phone call.
To be fair, lowest TCO can be the decision driver for applications that do not have high service-level requirements: ones that don't need to run 24x7 and can fail without impacting your business. We find many open source applications running such applications. This is often the stealthy entrance of open source products into Global 2000 companies. It's clear that there are not many budget dollars for applications that are nice to have but have low-business impact.
Widely held as the fastest growing database, a great deal has been written about the success of MySQL and, as an open source application, it gives users a low TCO among its many other benefits. However, some of this growth is due to its use in very simple, single user applications. For example, Gartner did not include MySQL in its new database study because the researcher didn't see the company's database as "enterprise class." An AMR Research study surveyed 140 information technology managers about open source databases. Overall there was satisfaction with price, performance, and ease of use of the open source database systems, but satisfaction lagged when it came to "scalability," the ability to handle large workloads, AMR noted. Further, it has been reported that some companies simply outgrow MySQL and determine that they need the "scalability and server redundancy of Oracle's database clustering technology."
Then, TCO by itself is not enough to drive key business-critical application decisions. A key driver seems to be "enterprise class." But what does "enterprise class" mean? The answer can be seen above: scalable or the ability to handle large work loads, redundancy, and close to zero downtime. In other words, meeting the needs of real-world, mission-critical applications, not tracking my wine collection.
