Prof. Dr. Carsten Griwodz
Lecturer Prof. Dr. Carsten Griwodz (Simula Research Laboratory, Oslo, Norway)
Title Blurring the Boundaries between Local and Remote PCIe Resources using Device Lending
Date Tuesday 22/05/2018, 11.00- 12.00
Location S3|20 Rundeturmstr. 10, Darmstadt
Room 111
Currently, small compute clusters consist of computing nodes interconnected by some high-speed networking technology. For the most part, operating systems are isolated and communication between compute nodes occurs at the application level. Flexibility is provided by virtual machines, but these are primarily aim to subdivide resource of one compute node, not to extend the hardware resource availability beyond a single node. Adding new hardware resources to individual compute nodes does usually imply adding new hardware modules into that compute node. We claim that today’s systems can be more flexible, at least with PCI Express (PCIe) interconnects, but not necessarily restricted to it.

For machines that are interconnected in PCIe clusters, we proposed Device Lending as an alternative approach to flexible and dynamic hardware customisation. By exploiting the memory addressing capabilities inherent in PCIe networks, individual PCIe-attached resources can be assigned and reassigned to different machines; virtual as well as physical. Systems can borrow resources from remote machines and lend their own devices to other systems, effectively contributing to a dynamic pool of PCIe resources shared among computing instances running in the cluster. Each resource is fully decoupled from the machine it physically resides in. Our solution blurs the distinction between virtualised and physical hardware architecture, and provides us with a novel approach to virtualising IO resources.

We show results for remote GPUs, network cards and disks, and show further that the idea can be generalised by demonstrating the direct communication between a GPU and a remote NVMe disk.

Finally, we discuss the challenges in extending the range of Device Lending beyond the PCIe fabric in tightly coupled clusters.
Carsten Griwodz leads the Media Department at the Norwegian research company Simula Research Laboratory AS, Norway, and is professor at the University of Oslo.

He received his Diploma in Computer Science from the University of Paderborn, Germany, in 1993. From 1993 to 1997, he worked at the IBM European Networking Center in Heidelberg, Germany. In 1997 he joined the Multimedia Communications Lab at Darmstadt University of Technology, Germany, where he obtained his doctoral degree in 2000. He joined the University of Oslo in 2000 and Simula Research Laboratory in 2005.

Carsten’s research interest is the performance of multimedia systems. He is concerned with streaming media, which includes all kinds of media that are transported over the Internet with a temporal demand, including stored and live video as well as games and immersive systems. To achieve this, he wants to advance operating system and protocol support, parallel processing and the understanding of the human experience.