In Visual Studio 2010, we are changing our load test licensing model. In VS 2005 and VS 2008, we shipped the load agent, which was licensed by CPU on the machine generating load. In Visual Studio 2010 we are changing our license model to a virtual user based model. This new license model offers a number of advantages for you, which is ultimately why we chose to make the change:

  1. Still way less expensive than our competition.
  2. Enables better purchasing planning and allows an apples to apples price comparison with competitors.
  3. Enables more flexible machine allocation for load generation.
  4. Enables you to use agents for more than just load testing.

Still Way Less Expensive than our Competitors

Your initial reaction may be “Groan – that means that Microsoft is going to be just as expensive as those other tools!” But that is not the case at all, we were careful to maintain the per-virtual-user price we set out initially with VS 2005. With VS 2005 and VS 2008 load agents, the price was around $5,000 per load agent CPU, and our general guidance was that for a typical load test expect around 1,000 virtual users per CPU. We are not yet disclosing our pricing yet, but I can tell you our goal is to stay in this same ball park with VS 2010.

Better Planning and Comparison

With the VS 2008 load agent, we often get questions from customers doing purchasing planning asking “How many load agents do we need to purchase? We are planning to test up to 5,000 virtual users.” To which our answer with VS 2008 was “we do not know, it depends on your application and test scripts.” Of course this it difficult to know how many agents to purchase until actually doing testing, which was often too late. With virtual user licenses, purchasers will know exactly how many licenses to buy.

The old CPU-based license model also makes it very difficult to compare prices with competitive solutions. Most competitive products are licensed by virtual user and data collectors. If you know how many virtual users you want to test to, but do not know how many agents you will need to generate that number of users, it is impossible to make a comparison. With the Visual Studio Load Test Virtual User Packs 2010, if you know the virtual user count you want to test to, you will know exactly how many licenses to purchase, and be able to compare directly with competitive solutions you may consider.

Enables More Flexibility with Load Generators

The virtual user license offers flexibility with the machines you use as load generators.

With VS 2008, to get the full value of the per-CPU license, you had to run on fast CPUs, often requiring new hardware purchases. Also the license was locked to a particular machine, restricting which machines you could use as load generators. With Visual Studio 2010, you can now run virtual users on older hardware with no “penalty”, as you can line up as many older machines as you wish to generate the target number of virtual users. Also, the virtual user license is now tied to the controller, not the agent machine, so you are allowed to move agent machines in and out of the agent pool.

For some tests, you may run out of some other resources before running out of CPU. The most common case for this in VS 2008 was load agents running out of memory before CPU (especially for web tests with very large post bodies or very large responses), which prevented customers from realizing the full value of their license. With the virtual user license, if this happens you can simply add more machines to the agent pool to achieve the load you are targeting.

Visual Studio 2010 Agents: More than just Load Generators

With the high cost of the agent license, we did not have a viable solution for distributed functional testing. In Visual Studio 2010, agents are now included at no extra cost with VS Premium, Ultimate, and Test Elements. We’ve added Data Collection facility to agents, and added new UI automation test type, which opens up a bunch of new scenarios for using agents.

What if I already have VS 2008 Load Agents?

If you have purchased VS 2008 load agents with software assurance, you will be able to migrate your existing licenses to a commiserate set of Virtual User License Packs. We will iron out the details and mechanics of this once we get closer to RTM.

Conclusion

You can see there are many advantages to you with the new licensing model.

Ed.