Xen Project Membership Spotlight: Citrix

The Xen Project is comprised of a diverse set of member companies and contributors that are committed to the growth and success of the Xen Project Hypervisor. The Xen Project Hypervisor is a staple technology for server and cloud vendors, and is gaining traction in the embedded, security and automotive space. This blog series highlights the companies contributing to the changes and growth being made to the Xen Project, and how the Xen Project technology bolsters their business.

Name: James Bulpin
Title: Senior Director, Technology
Company: Citrix

When did you join the Xen Project and why/how is your organizations involved?
Citrix was a founding member of the Xen Project and, through the work of XenSource, which was acquired by Citrix in 2007, has been active in the open-source Xen Project hypervisor since 2005. Personally I’ve been involved with Xen since its very early days as a research project in the early 2000s.
Citrix is a significant contributor to, consumer of, and leader in the Xen Project. The Xen Project hypervisor forms the core of our XenServer platform, which has widespread use as a free platform for general purpose server virtualization, a commercial server virtualization and cloud hosting platform, a technology component in other Citrix products, and the platform of choice for Citrix’s flagship application and desktop delivery solutions. We see the Xen Project hypervisor as a powerful, flexible and secure foundation on top of which a wide variety of products, solutions and services can be built.
How does your involvement benefit your company?
A hypervisor is a complex entity, requiring deep knowledge of many areas of technology in order to implement successfully; it requires deep knowledge of CPU virtualization instructions, interrupt and exception handling, efficient resource management (such as CPU scheduling), a wide variety of I/O virtualization mechanisms, multiple mechanisms to boot virtual machines, multiple security boundaries, and so on. By collaborating with other vendors who share our need for an efficient, flexible hypervisor, and with vendors whose technology can be enabled through the hypervisor, we are able to achieve far more than any one of us could on our own. Ultimately this allows us to bring a very sophisticated solution to our customers at a low cost.
How does the Xen Project’s technology help your business?
In addition to the Xen Project hypervisor and other components being a core part of our commercial products, Xen Project has enabled rapid multi-vendor innovation that helps us to get ahead of the competition and helps our customers solve their problems. The open-source nature of the hypervisor removes barriers to collaboration and accelerates innovation. In recent years this has allowed Citrix and its partners to be first to market with innovative solutions such as virtualized GPUs with NVIDIA and Intel, VM introspection with BitDefender, and hypervisor live patching built in collaboration with Oracle, Amazon and others.
What are some of the major changes you see with virtualization and the transition to cloud native computing?
Over time we expect to see virtualization creeping up the stack. Hypervisors and the CPU virtualization instructions they rely upon virtualize at the lowest layers; PaaS and cloud-native services are effectively performing virtualization further up the stack (e.g. a Linux container virtualizes the kernel, and a “lambda” type function virtualizes a language runtime environment).
Although we’ve seen FUD that argues that these high levels of virtualization render the lower levels obsolete, in reality the different layers of virtualization bring different values to an overall cloud computing platform. We see that cloud platforms will evolve to use multiple virtualization techniques, albeit in a more integrated fashion than we see today. For example we anticipate that platforms providing container or PaaS services will actually rely on hypervisor techniques and CPU virtualization instructions to provide a strong security boundary (particularly in a multi-tenant context) at the bottom, and use container technology, software sandboxing and other lightweight virtualization techniques on top. Such as solution will likely have a very tight integration between the layers to minimize overhead. The small, flexible, and efficient structure of the Xen Project hypervisor makes it an attractive technology to embed in a system like this.
What advice would you give someone considering joining the Xen Project?
Although many members will join with a particular goal in mind, such as adding functionality to the hypervisor to enable their own products/technology, I would recommend looking beyond that and considering how to best leverage the opportunity to collaborate with the other members. For example, adding a mechanism to Xen to enable the use of a particular piece of hardware is valuable in its own right, however using the Project to collaborate with a vendor that can exploit that mechanism and that piece of hardware and take it to a broader customer base could end up providing an ever better return on investment. I would also encourage new joiners to get involved in code and design review of other members’ contributions. This is a great way to quickly learn about Xen, helps improve the code, and fuels the necessary “give and take” model that an open source project needs to operate successfully.
What excites you most about the future of Xen?
Xen has already proven itself in a number of diverse use-cases including traditional server virtualization, large-scale cloud computing, and client virtualization. I’m excited to see Xen, as a reusable technology component, grow in new use-cases such as edge computing, automotive, aviation and aerospace. Xen’s flexibility, small footprint, and OS independence make it a good fit in these growing sectors.