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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.

Improving Xen idle power efficiency

Power management has become increasingly important in large-scale datacenters to address costs and limitations in cooling or power delivery, and it is much critical in mobile client where battery lifecycle is considered as one of the critical characteristics of the platform of choice. Good power management helps to achieve great energy efficiency. Virtualization imposes additional challenge to power management. It involves multiple software layers: VMM, OS, APP. For example, a good OS software stack may result in bad power consumption, if the hypervisor is not the timer unalignment, etc.

In this session, we will introduce what we did to improve power efficiency to achieve better power efficiency in both server and client virtualization environment.

In server side, we will introduce additional optimization technologies (e.g., eliminate unnecessary activities, align periodic timers to create long-idle period), to improve package C6 residency to be within 5% overhead with native. In client side, we will share our client power optimization technologies (e.g. graphics, ATA and wireless), which successfully reduce XenClient idle power overhead to be within 5%.

Yang Zhang, Intel

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