Extended Static Analysis for Estimating WCET in Distributed Real Time Systems

In most distributed real-time systems, it is required to estimate the worst-case execution time (WCET) of a program. It is important to consider timing effects of the kernel service time and I/O operations in order to improve the accuracy of WCET. In this work, we attempt to extend the conventional static analysis of source programs for calculating WCET by adding the timing effects of queue wait time in I/O operations and scheduling modules. We analyzed the source code of system calls for queue handling and I/O operations in Linux-kernel. Our implementation experience demonstrates the effectiveness of the proposed approach.