HP and Citrix are upgrading to Platinum membership. HP was previously a Gold member and Citrix was a Silver member. Other Platinum members include Fujitsu, IBM, Intel , NEC, Oracle, Qualcomm Innovation Center and Samsung. HP and Citrix will each take a seat on the board of directors.

Many of HP's products -- servers, printers, networking equipment and more -- are already running Linux. HP's membership upgrade is partly recognition Linux will help drive collaborative development going forward.

"Linux is a strategic asset for all major technology companies," said Eileen Evans, vice president and associate general counsel of Cloud Computing and Open Source at HP. "With our Linux Foundation Platinum membership, we will have a variety of ways to maximize our investment in Linux and collaborative development that advances our own business as well as greater industry innovation."

Open Source and the Cloud

For its part, Citrix is a committed supporter of open source software and is a major participant in both Xen and Apache CloudStack. Both projects provide the underpinnings for some of the world's largest cloud computing environments.

The Xen hypervisor is a virtualization technology that enables server virtualization, a critical capability for cloud computing. Apache CloudStack software orchestrates virtualized environments so that they can work as an elastic compute environment. CloudStack is an open source cloud computing platform for creating, managing and deploying infrastructure services.

"The Linux Foundation provides a valued environment for collaborating across projects, companies and industries," said Mark Hinkle, senior director of Cloud Computing Communities at Citrix. "Upgrading our membership level and increasing our investment in Linux and open source cloud computing are natural next steps as we work to advance cloud technologies to address the challenges facing enterprise users today."

IDC's New Report

The Linux Foundation provides a neutral environment that aims to accelerate and advance work on Linux, mobile and embedded development, open cloud, and other environments. The Linux Foundation hosted the industry's first CloudOpen event in August and is home to more than 150 members. The second annual LinuxCon Europe conference is being held in Barcelona, Spain, and runs through Thursday.

According to a new IDC white paper called "Open Source Cloud System Software," 94 percent of respondents -- of which there were both Windows and Linux users -- said collaboration and a vibrant open source ecosystem are important for cloud adoption.

What's more, 86 percent of respondents said they would either increase or maintain their current spending on Linux and open source software in support of private cloud in the next 12 months. Specifically, 47 percent said they would add more Linux and open source during that period.