Posted on April 21, 2014 at 17:19One would normally have a good sense of what the complexity of the task would require, and where needed you'd benchmark or profile the code to either confirm or improve that knowledge.
If you don't have access to equipment and tools, you can use simple indicators like toggling GPIO/LEDs measured on a scope, or measuring run-time with free running counters/timers, or cycle counters.
The key is to have experience, and be able to apply that to different contexts. Basically like driving to/from work everyday, and at different times, you get an appreciation about where accidents occur, where the police set up radar traps, and when/where congestion occurs.
