# Review of Task-Scheduling Methods for Heterogeneous Chips
## 3 Research Status of the Task-Scheduling Framework
### Centralized Scheduling Framework  
The centralized scheduling framework of heterogeneous chips manages the resource allocation and task scheduling of the whole system through a task scheduler. As shown in Figure 5a, NVIDIA Jetson AGX Orin [17] adopts a centralized task-scheduling framework. The central CPU core uniformly coordinates the allocation of hardware resources and dispatches tasks to the GPU, deep learning accelerator, and computer vision modules. The core advantage of this framework design lies in the centralized processing of scheduling  
\begin{table}
\begin{tabular}{c c c} \hline \hline
**Metric** & **Centralized Scheduling Framework** & **Distributed Scheduling Framework** \\ \hline \multirow{2}{*}{System Model} & Central scheduler manages all resources and & Decentralized nodes with \\  & task assignments. & autonomous schedulers. \\ \hline \multirow{2}{*}{Task Model} & Suited for tasks with simple dependencies. & Handles complex dependencies through \\  & & localized decision-making. \\ \hline \multirow{2}{*}{Scalability} & Limited as the central scheduler may become a & Enhanced through distributed management of \\  & performance bottleneck. & tasks and resources across multiple nodes. \\ \hline \multirow{2}{*}{Fault Tolerance} & Lower fault tolerance due to reliance on a & Higher fault tolerance through redundancy and \\  & single scheduler. & distribution of scheduling responsibilities. \\ \hline \multirow{2}{*}{Complexity} & Lower complexity arising from centralized task & Lower complexity due to decentralized task and \\  & and resource management. & resource management. \\ \hline \multirow{2}{*}{Adaptability} & Limited adaptability to dynamic changes in & High adaptability with local decision-making \\  & task requirements. & capabilities responsive to changes in \\  & & local environments. \\ \hline \multirow{2}{*}{Advantages} & Optimal resource allocation guarantees and & Elastic horizontal scaling and intrinsic \\  & deterministic execution timelines. & geographical redundancy. \\ \hline \multirow{2}{*}{Disadvantages} & Scalability bottleneck and & Potential consistency issues and latency \\  & single-point-of-failure vulnerability & sensitivity in wide-area deployments. \\ \hline \hline \end{tabular}
\end{table}
Table 1: Comparison of scheduling frameworks.  
Figure 5: Common task-scheduling frameworks, such as NVIDIA Jetson AGX Orin (**a**) and Intel Loihi 2 neuromorphic chip (**b**).  
decisions, which allows the system administrators or scheduling algorithms to have a global perspective so as to conduct unified resource optimization and task-scheduling decisions [6]. Since all decisions are based on comprehensive system state information, centralized scheduling often enables efficient resource utilization and low task response times.  
Although the centralized framework has the advantages of a global perspective and unified scheduling decisions in design, its limitations have become increasingly significant with the complexity of the heterogeneous chip architecture and the continuous expansion of the task's scale. First, the centralized framework is less scalable. As the core component of the system, the performance bottleneck of the central scheduler will gradually appear with the growth of the number and complexity of tasks, and it will be challenging to meet the requirements of efficient scheduling in the large-scale heterogeneous computing environment. At the same time, with the expansion of the system scale, the amount of data and computational complexity of the scheduler increase significantly, leading to a significant increase in its scheduling delay and system response time. Secondly, once the centralized framework fails, the task scheduling and resource management of the whole system will be paralyzed. It is often necessary to design redundancy or backup mechanisms for the central schedulers, but this will significantly increase the complexity and cost of the system.