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XenSummit has been a tremendous success this year. Thank you to all the speakers for contributing and to all the attendees for making XenSummit an interactive and fun conference with lots of discussions. You can find presentations on slideshare and videos on vimeo. We will also embedded both in the agenda. The slides are also available for download as zip file.

NUMA and Virtualization, the case of Xen

Having to deal with NUMA machines is becoming more and more common, and will likely continue to do so. Running typical virtualization workloads on such systems is particularly challenging, as Virtual Machines (VMs) are long lived processes with large memory footprints. This means one might incur really bad performance if the specific characteristics of the platform are not properly accounted for.

Extensive benchmarks are being performed, running memory intensive workloads inside Linux VMs hosted on NUMA hardware of different kinds and size. This is driving the design and development of a suite of new VM placement, scheduling and memory allocation policies for the Xen hypervisor and its toolstack.

The subset of such changes that has been implemented so far is already proving to be effective in yielding performance improvements, and the talk will illustrate these early results. It will also offer the chance for the Xen community to discuss about all the various aspects of this challenging problem and of drawing a roadmap for how to put together the best NUMA support ever.

Dario Faggioli, Citrix

Dario Faggioli has interacted with the Linux kernel community in the domain of scheduling during his PhD on real-time systems. He now works for Citrix on the Xen Open Source project. He spent the last months on investigating and trying to improve the performance of virtualization workloads on NUMA systems.

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