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