Summary
Keywords
Full Transcript
"To block or not to block?" is the single, most fundamental question determining the architecture of your embedded software. In fact, the issue of blocking is the most important discussion we can have in embedded programming, even though many embedded developers don't realize that. A traditional blocking RTOS is still the dominant approach, but this is changing. Concurrency experts increasingly see blocking as a *technical dept*, and therefore, non-blocking, asynchronous architectures are gaining more traction, especially in mission-critical systems. #embeddedprogramming #rtos #async #eventdriven Contents with Timestamps: ------------------------- 0:32 Blocking definition and types of blocking in embedded systems 0:42 Busy polling 1:17 Blocking in an RTOS (by context switching) 2:00 Why is blocking so important? 2:52 Software composability 3:18 State machine as an alternative to blocking 4:50 Input-driven state machine example 5:15 RTOS solution to non-composability of blocking code 5:58 Cost of blocking in RTOS: private stacks for all threads 6:10 Traditional embedded architectures classified by blocking/non-blocking 7:13 Changing landscape of embedded architectures 7:52 Event-driven programming (non-blocking) with traditional RTOS 8:00 Event-driven programming at NASA JPL 8:55 Event-driven state machines (e.g., UML statecharts) 9:25 Efficient non-blocking real-time kernels 10:05 Preemptive non-blocking kernel compatible with RMS/RMA 10:30 Summary: blocking as the defining characteristic of embedded architectures 10:45 Mission-critical architectures are predominantly non-blocking End Notes: ---------- NOTE: there is no specific project download for this lesson. Companion web page to this video course https://www.state-machine.com/video-course/ GitHub repository for projects for this video course: https://github.com/QuantumLeaps/modern-embedded-programming-course Transcript of this lesson: https://www.state-machine.com/course/lesson-50.txt Referenced articles: ------------------- PX5 RTOS, "PX5 RTOS User Guide Version 5.1.1," https://px5rtos.com/px5-rtos-user-guides/ (requires login to download) David M. Cummings, "Managing Concurrency in Complex Embedded Systems," Kelly Technology Group 2014 https://www.state-machine.com/doc/Cummings1006.pdf D. Kalinsky Associates, "Messages for Intertask Communication," 2010 https://www.state-machine.com/doc/Kalinsky2010.pdf D. Kalinsky Associates, "New Directions in RTOS Kernels," 2014 https://www.state-machine.com/doc/Kalinsky2014.pdf Herb Sutter, "Prefer Using Active Objects Instead of Naked Threads," Dr. Dobbs Journal, 2010 https://www.state-machine.com/doc/Sutter2010a.pdf Music credits: -------------- The background music comes from: https://www.bensound.com/royalty-free-music/track/straight
Continue this lesson in the app
Install CourseHive on Android or iOS to keep learning while you move.
