Events Calendar

CS Colloquium: David Chu (Microsoft Research) - Surmounting two challenges of cloud gaming for mobile devices: network latency and server multi-tenancy

Speaker: David Chu, Microsoft Research

Talk Title: Surmounting two challenges of cloud gaming for mobile devices: network latency and server multi-tenancy

Series: CS Colloquium

Abstract: Gaming on mobile devices is very popular. Cloud gaming such as Sony PlayStation's Now -- where remote servers perform game execution and rendering on behalf of thin clients that simply send input and display output frames -- appears to be well-suited for mobile devices, promising any device the ability to play any game any time. However, cloud gaming must confront network latency and server multi-tenancy. This talk introduces these two challenges, and our two respective solutions, DeLorean and DeeJay.

For latency, wireless network round trip times (RTTs) often exceed thresholds above which gamers find responsiveness acceptable. We present DeLorean, a speculative execution system for mobile cloud gaming that is able to mask latency. DeLorean produces speculative rendered frames of future possible outcomes, delivering them to the client one entire RTT ahead of time; clients perceive little latency. To achieve this, DeLorean combines: 1) future input prediction; 2) state space subsampling and time shifting; 3) misprediction compensation; and 4) bandwidth compression. This work is a collaboration with the University of Michigan.

For multi-tenancy, a single server must carefully schedule the GPU across multiple game instances that each have their own real-time latency and throughput requirements. Moreover, it must gracefully handle overload when more clients join than anticipated. We are in the process of building DeeJay, a system that 1) schedules GPU-bound jobs with latency and throughput constraints, and that 2) minimally degrades visual game quality upon system overload.

To evaluate both DeLorean and DeeJay, we use two high quality, commercially-released games: a twitch-based first person shooter, Doom3, and a role playing game, Fable3.

Biography: David Chu is a researcher at Microsoft Research in Redmond where he works on mobile systems with an emphasis on mobile gaming. He is also interested in sensing and context for the mobile OS. His work has appeared in The Verge, Engadget and Wired. David received his Ph.D. and M.S. from the University of California, Berkeley, and his B.S. from the University of Virginia.

Host: Ramesh Govindan

Location: SAL 222

Audiences: Everyone Is Invited

Contact: Assistant to CS chair