Globecom, wireless networking forum, talk on smartphones by Roy Want

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Last week, I attended Globecom'10 .

Roy Want (Intel) gave a talk on smartphones in Globecom. He started by showing the market trends for cellphones smartphones and laptops. Cellphones and smartphones grow so quickly that they dwarf the laptop market (which is growing with a healthy 20%). Roy, then, asked the following question: "Will one day will we be computing on the smartphones?" He said that in order for that to happen we need to overcome the poor UI experience of smartphones.

As part of these introductory slides, Roy showed a picture of the Intel atom processor for smartphones. It is smaller than rice grain yet is the brain of smartphone and x86 compatible, so these chips can bring After the presentation, over dinner, I asked Roy about why not put a dozen of these atom processors in one smartphone, given that they take virtually no space. Turns out this is currently not very feasible, because these processors are pretty battery-hungry, even though they are very tiny.

Roy's talk then focused on three things: context aware operation, resource sharing, and processor acceleration.

For context aware operation, the goal is to prioritize which sensors get focus.
iPhone made sensing mainstream, there are a dozen sensors in the iphone: accelerometer, light, touch screen, gps, mic, proximity, magnetometer, etc. But they cannot be always on. Roy mentioned the need for a triage processor to prioritize the sensors, processors, radio on the smartphone.

For resource sharing, the goal is to make maximum use of the computation device rich environment. Can the smartphone seamlessly share a nearby display, network, storage, or other peripherals. He gave the example of editing a movie at home. He calls this dynamic composable computing. At this point, he demoed a VNC running over the smartphone. The smartphone was running Linux, and from the laptop he sshed to the smartphone and started a remote X-window session which is hosted at the smartphone but displayed at the laptop.

For the processor acceleration, Roy asked the question of whether it is possible to share the processor by migrating an application from one device to the other. He said that generally the cleanest way of doing this is to migrate the entire OS, virtual machine. And for this he mentioned Satya's work at CMU on incremental VM synchronization. By doing VM synchronization in an incremental manner only for the parts that got changed, it is possible to improve the performance and reduce the latency of this synchronization to work in real-time. The example he gave was that your phone shares your home computer does something, and your work computer also gets synchronized with your work computer so you can continue at your work computer when you arrive there. (Turns out this is now common-place. Xen provides this. Amazon makes use of this for replicating your machine with them and checkpoint your service.)

My colleague Chunming Qiao asked Roy a question on whether he is aware of the single system VM migration made possible by Kerrighed. While traditional VM approaches are fitting multiple VMs in one physical machine, Kerrighed tries to run one VM over multiple physical machines. This is beneficial for providing more CPU, RAM, storage resources to your VM. Your VM can grow on the fly even beyond the limitations of the physical host. This will obviously be beneficial for your smartphone, as it can now use the CPU, RAM, storage resources from the other computers.

This talk was very interesting to me because we are trying to build a 1000 smartphone (cloud-enabled) testbed at UB. More on this later, once we make more progress on this.

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