# Design exercise: GPU Utilization

> Compute occupancy, memory bandwidth, kernel launch overhead, tensor parallelism, profiling, and saturation. Implement designOutline() returning non-empty values for: profile, bottleneckClass, saturationPlan. Each value must name a concrete mechanism or decision.

Canonical: https://learn.significanthobbies.com/curriculum/drills/practice-gpu-utilization

Compute occupancy, memory bandwidth, kernel launch overhead, tensor parallelism, profiling, and saturation. Implement designOutline() returning non-empty values for: profile, bottleneckClass, saturationPlan. Each value must name a concrete mechanism or decision.

## The mechanism

GPU utilization is not one percentage. Profile kernel occupancy, memory bandwidth, queue gaps, communication, and batch shape to find whether the workload is compute-, memory-, or launch-bound.

## Expected evidence

A design outline with profile, bottleneckClass, saturationPlan plus an explicit failure mode or trade-off.

## Hints

- Name the failure mode before selecting the mechanism.

## Sources and practice

- [Stanford CS149 Lecture 7 — GPU Architecture and CUDA Programming](https://gfxcourses.stanford.edu/cs149/fall23content/media/gpucuda/07_gpuarch.pdf)
- [Efficiently Scaling Transformer Inference](https://arxiv.org/abs/2211.05102)
- [FlashAttention: Fast and Memory-Efficient Exact Attention with IO-Awareness](https://arxiv.org/abs/2205.14135)
- [Stanford CS336 — Lecture 5: GPUs (Language Modeling from Scratch, Spring 2025)](https://www.youtube.com/watch?v=6OBtO9niT00)
- [Roofline: An Insightful Visual Performance Model for Multicore Architectures (UCB/EECS-2008-134)](https://www2.eecs.berkeley.edu/Pubs/TechRpts/2008/EECS-2008-134.pdf)
- [NVIDIA Nsight Systems Documentation](https://docs.nvidia.com/nsight-systems/)
- [Study GPU Utilization](https://learn.significanthobbies.com/curriculum/concepts/gpu-utilization)
- [Try the interactive drill](https://learn.significanthobbies.com/drills/practice-gpu-utilization)
- [All practice briefs](https://learn.significanthobbies.com/curriculum/drills/)