Real-Time Operating Systems Overview

Real-Time OS defined Real-Time OS Characteristics Examples of Real-Time Operating

Systems Applications

Real-Time operating system is: “one whose correctness involves both the

logical correctness of the outputs and their timeliness”.

Practical Example

Hard Real-Time OS

Firm Real-Time OS

Soft Real-Time OS

Must handle multiple threads

Must be able to prioritize tasks

Must be able to schedule based on priorities

Produce results in predictable timeframe

Admission Control

Resource Reservation

Hard/Soft Real-Time Guarantees

Small, Proprietary Kernels

Quality of Service Kernels

Real-Time Extensions of Commercial Operating Systems

Aircraft Flight Control Systems Maintenance Diagnostics

Automotive Control and Monitoring Systems Safety Critical Systems

Android ????????

Definition

Hard Real-Time OS

Safety Critical Applications were results are time critical

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MONIGIA, BHUPINDER S., MADISETTI, VIJAY K., 2010, Reliable real-time applications on Android OS. http://users.ece.gatech.edu/~vkm/Android_Real_Time.pdf.

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NAGAURA, WATARU, SUZUKI, SHOJI 1998. EMERALDS-OSEK: A small real-time operating system for automotive control. Society of Automotive Engineers Congress and Exposition, 1999.