A few weeks my colleague Bob, blogged (here) about how GPU-passthrough on XenServer under OpenStack had been achieved by the xlcloud project. This is a delightful demonstration of Citrix’s open technology stance. Although Citrix has heavily invested in CloudStack, over the last few years we have remained active in OpenStack development. You can find out more about building products using XenServer as the hypervisor using both OpenStack and CloudStack, here.


XLcloud – a fascinating project

XLcloud is an open sourced project, with sound financial backing ($Millions) and technological commitment from some heavyweight companies including Bull SAS.

The XLcloud project strives to establish the demonstration of a High Performance Cloud Computing (HPCC) platform based on OpenStack, that is designed to run a representative set of compute intensive workloads, including more specifically interactive games, interactive simulations and 3D graphics. XLcloud is a three-year long collaborative project funded by the French FSN (Fonds national pour la Société Numérique) programme. It’s one of those great projects where state funding has enabled both commercial and academic organisations to collaborate to define large scale technologies. They’ve have some great names involved in the consortium (see here) with a wealth of experience in networking, hosting and graphics.

The project has some really clear goals and projects to tackle: XLcloud will deliver the following use-cases to provide a demonstration of the implementation of the outputs of the XLcloud research project:

  • MVIC (“Maquette Virtuelle Interactive et Collaborative”): Interactive and collaborative virtual prototyping. See more.
  • Human Body Visualisation: Research areas in online medical education. See more.
  • MFIC (“Mécanique des Fluides Interactive pour le Cloud”): Interactive computation fluid dynamics for the cloud. See more.
  • Cloud Gaming: Industry of 3D video games. See more.
  • Compute Plants (HPC clouds Research & Industry). See more.


XLcloud – GPU passthrough

XLCloud have blogged about how they have enabled GPU-passthrough via OpenStack for XenServer, here. In fact they have enabled the support of generic PCI-passthrough in the XenAPI driver of Nova. XLCloud have been mainly working with the NVIDIA GRID K2 graphics card but also other more gaming focussed NVIDIA cards such as the NVIDIA K520 and also the NVIDIA M2070Q. Being an open source project you can follow XLcloud’s progress and check out their test results benchmarking pass-through relative to bare metal e.g. for the NVIDIA K340. You can check out the code and software as it emerges following the links on this page. Guillaume form the project has posted a great video testing the system using the Unigine benchmarks, that you can get here (the VM was deployed with Heat and Chef Solo). XLcloud have blogged about some of their reasons for feeling NVIDIA Kepler architecture is particularly well suited to their HPC and graphical needs, here.

XenServer as a platform

This project shows the power of XenServer as a platform, there has been a lot of publicity recently about the amazing industry technologies using GPUs (e.g. vGPU, hardware shared GPUs) exploited under a stack of Citrix XenDesktop, HDX 3D Pro and XenServer. However projects such as XLcloud keep us on our toes and provide valuable technology streams, ensuring we don’t become introspective about our own internal technologies. By considering other users such as OpenStack and XLcloud and their needs we ensure XenServer as a platform evolves to allow us to expand our own technologies.  XenServer is therefore continually evolving to consider the needs of multiple stacks and products built on top of it, Linux users, the CloudPlatform products and of course XenDesktop.

Our conversation with XLcloud has helped Citrix gain a better understanding of both Graphical use cases but also the needs and direction of HPC users. XLcloud have blogged their use of XenServer and KVM, here.

Final thoughts – Consortiums are great!

Most big technological achievements need to involve multiple technologies, companies and draw in the best from leading-edge research and academia. XLcloud is hoping to define a cloud platform of international standing. In a similar way that international telescope and space programs are too large and need technical input from the entire community, Citrix and XenServer are very pleased to have been invited to this particular party!