Challenges

Challenges of Real-time Scheduling in Virtual Machine System

Embedded systems evolution

Positive impact in the perspective of CE market

<-> Challenging problems arise

Complex design makes difficult to analyze the system performance, and properties.

e.g.) scheduling in complex system

The solution: Abstraction helps to deal with the complexity. Hierarchical design practices.

e.g.) compositional scheduling framework

Scheduling in virtual machine

1. Hierarchical scheduling: VM-level, process-level

2. How to provide real-time scheduling?

Problems of real-time scheduling in virtual machine

1. Physical time awareness inside virtual machine

2. Task information awareness inside hypervisor

Therefore, it is impossible to schedule tasks inside guest OS at accurate physical time.

How to provide global timing property?

Real-time guarantee using bandwidth allocation (translates global timing problem into bandwidth allocation problem)

Real-time scheduling in virtual machine

Present real cases

Prove that there are critical requirements of real-time guarantee!

Scaling problems? (scalable solution?) If possible, present it.

Compositional scheduling framework

incorporate the theory into a real system

introduce 'quantized periodic scheduling interface'

construct an algorithm that finds the optimal interface