What is Static Mapping?

A fundamental concept in computer science, static mapping is a technique where the assignment of resources to a task is predetermined and remains unchanged during execution.

Understanding Static Mapping

Static mapping involves fixing the relationship between resources and tasks before a system or program begins its operation. Unlike dynamic mapping, where resource assignments can shift and adapt at runtime, static mapping establishes a permanent link.

This approach is defined by two core characteristics:

• Predetermined Assignment: Resource allocation decisions are made entirely at the design, compilation, or configuration stage, before execution starts.
• Remains Unchanged During Execution: Once the system is running, these assigned links between tasks and resources are fixed and cannot be altered or reallocated.

This immutability can offer advantages in terms of predictability and potentially simpler control mechanisms, especially in environments where runtime flexibility is not required or could introduce undesirable overhead or complexity.

How Static Mapping Works

Implementing static mapping typically involves careful planning and analysis during the system's design phase. Resources are analyzed, and tasks requiring them are identified. A fixed map or configuration is then created that dictates which specific resource will serve which specific task.

The reference highlights that this process involves:

1. Mapping at the Design Stage: The crucial decisions about resource-to-task assignments are made upfront, during the system's architecture or setup phase.
2. Finding an Efficient Solution: Determining the optimal fixed mapping can be a complex problem. The reference notes that designers may employ exact or search-based approaches to find an efficient solution that meets system requirements (like performance, efficiency, or reliability) based on the predetermined assignments.

Practical Example: Mapping Cores to Routers

A clear example provided by the reference is the application of static mapping in mapping cores to routers. In systems like complex multi-core processors or Networks-on-Chip (NoCs), static mapping can assign a particular processing core to a specific interface or router within the communication network. This means that during operation, communications initiated by that core will always use the pathway defined by its statically assigned router, rather than dynamically finding a route based on current network conditions.

Key Characteristics Summary

To summarize the essence of static mapping:

This fixed approach contrasts with dynamic methods that allow for runtime changes, offering different trade-offs in terms of performance, flexibility, and complexity depending on the application's needs.