Hands-On System Programming with Linux

The Mars Pathfinder mission in brief

Very interestingly, this precise scenario priority inversion played out quite dramatically in a literally out of this world setting: on the surface of Mars! NASA successfully landed a robot spacecraft (the Pathfinder Lander) on the Martian surface on July 4, 1997; it then proceeded to unload and deploy a smaller robot—the Sojourner Rover—onto the surface. However, controllers found that the lander ran into problems—every so often it would reboot. Detailed analysis of the live telemetry feed ultimately revealed the underlying issue—it was the software, which had hit a priority inversion issue! To their immense credit, NASA's Jet Propulsion Laboratory (JPL) team, along with engineers from Wind River, the ...