Thread Carefully: Preventing Starvation in the ROS 2 Multithreaded Executor

over utilized. Fig. 6. Starvation for τ4 in the multithreaded executor when the mutually exclusive group g = {τ3, τ4} is under utilized. Fig. 7. Starvation for τ4 in the multithreaded executor for the mutually [...] 5), τ2 = (1, 0.5), τ3 = (1, 0.5), and τ4 = (1, 0.01), where g = {τ3, τ4} is a mutually exclusive callback group. Since τ1 and τ2 occupy both threads in parallel, τ4 is removed from the wait set once τ3 starts [...] s to L = (1/3) plus the workload of task τ4. Furthermore, L + WCET(τ4) ≈ 0.334+0.01 = 0.344 is less than the deadline of 0.5, and the response time of task τ4 is bounded according to Theorem 1 by Jiang …