於嵌入式Linux系統，當週邊裝置發生硬體中斷時，底層驅動程式將會通知I/O事件至上層應用程式，由應用程式決定該如何對I/O事件進行後續的應用服務，故開發人員對於通知I/O事件之時間成本須有一定的掌握度，才能確保應用程式能即時對I/O事件進行處理。
　　本論文於NuMaker-IIoT-NUC980與NanoPi-M1等嵌入式開發板，針對Blocking I/O與Non-blocking I/O應用情境，使用I/O Multiplexing之系統呼叫select、poll與epoll，以及Signal等現有的I/O事件通知機制，量測各I/O事件通知機制從底層驅動程式之硬體中斷服務程序，通知I/O事件至上層應用程式之時間差，並將該時間差用於比較與評估I/O事件通知機制之效能與使用時機。
　　研究成果如下:I/O Multiplexing效能相較於Signal快，故若有較高即時性需求時，建議使用I/O Multiplexing。於Blocking I/O情境，poll適用於File descriptor數量為1的狀況，其餘狀況建議使用epoll。於Non-blocking I/O情境，poll適用於File descriptor數量小於等於2的狀況，其餘狀況建議使用epoll。於各情境，poll或epoll效能皆相較於select快，故不建議使用select。

In the embedded Linux system, when a hardware interrupt occurs in a peripheral device, the low-level driver will notify the I/O event to the high-level application. Therefore, the developers must know about the time cost of notifying I/O events to ensure that the application can handle I/O events in real-time.
　　The experiments of this thesis is implemented on the NuMaker-IIoT-NUC980 and NanoPi-M1 (embedded) development boards. We focus on situations of blocking I/O and non-blocking I/O, using the existing I/O event notification mechanisms, including Signal and I/O Multiplexing (select, poll, and epoll). The notification time, measured from the interrupt service routine of the low-level driver and the notification to the high-level application, is used to evaluate the performance and the timing of using each I/O event notification mechanism.
　　According to the evaluation results, the performance of I/O Multiplexing is better than Signal. If there is a higher real-time requirement, I/O Multiplexing is recommended. In situations of blocking I/O, poll applies to a condition that the number of file descriptors is one, epoll applies to the other conditions. In situations of non-blocking I/O, poll applies to a condition that the number of file descriptors is less than or equal to two, epoll applies to the other conditions. In each situation, both poll and epoll are better than select. Therefore, select is not recommended.

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