The Reduction Tree Idea
Halving active threads each step.
What Reduction Means
A reduction collapses a whole array into one value, like summing every element down to a single total. It is one of the most common GPU patterns. 🌳
The Sequential Way Is Slow
On a CPU you add elements one after another. That is O(n) sequential steps, so a million numbers means a million dependent additions in a row.
All lessons in this course
- The Reduction Tree Idea
- Killing Warp Divergence
- Sequential Addressing
- Multi-Block Final Reduction