Cloud vendor Skytap this week said it has joined forces with Hewlett-Packard to make it easier to stress test your new software with hundreds or thousands of simulated end users in the cloud, without taxing your data center.

Skytap offers a Virtual Lab where developers may test drive their applications, building test environments from its broad library of operating systems, databases and middleware. Through a partnership with HP, HP's LoadRunner testing tool can now be used to build test scenarios that will tax an application's limits. The tests can be set up, managed and torn down through HP's Quality Center, which is able to launch them in a Skytap cloud. The tests run as virtual workloads under VMware's ESX Server.

Cloud computing has been advocated as a lower cost way to off-load spikes in workloads from the data center. Ian Knox, director of product management at Skytap, thinks software test and quality assurance is one of those spiky loads that belongs in the cloud.

"We focus on specific solutions in the dev/test world," he explained, with customers typically paying $1,000 to $10,000 a month for cloud-based testing. Skytap also partners with Microsoft to enable Visual Studio Team System testing in the Skytap Virtual Lab.

HP Quality Center is software that imposes standard procedures on each round of software testing. It maintains testing and release cycles for software under development, and builds testing around risk factors to the business. It can deploy test environments in the cloud when in-house resources are already fully committed, removing a test and development bottleneck, said Tim Van Ash, director of products for HP Software as a Service.

Use of the Skytap/HP combination enables customers "to accelerate their testing cycles and significantly reduce costs," he said in the announcement Wednesday.

Another way to use Virtual Lab and Quality Center is for developers at a U.S. company to produce code that's tested by a team in Mumbai, India. By storing the tests and their results, Virtual Lab can show where the application fails by letting the developers call up the stored tests and run them again to the break point.

Skytap users can also use HP Cloud Assure, an HP offering that helps customers safely implement cloud services. Cloud Assure lets an application be evaluated through software-as-a-service services for security and performance, before it goes into production.

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