← AI Terminology

Structured Sparsity

Structured sparsity zeroes parameters in hardware-friendly patterns (blocks, channels, N:M) so accelerators can skip compute, unlike irregular unstructured pruning.

It aims for real wall-clock speedups, not only parameter counts.
Why It Matters in AI
Unstructured 90% sparse models often do not run faster without special kernels. Structured patterns (e.g. 2:4) map to Sparse Tensor Cores and deliver measured speedups — key for efficient deployment research.
Key Points
Aspect Description
Metric Achieved speedup, not only % zeros
Related Pruning, MoE (conditional compute)
Hardware NVIDIA sparse tensor cores for 2:4
Patterns Block, filter, N:M (2:4), head pruning
Training Sparse aware training or prune+finetune
Vs unstructured Easier speedups; sometimes more accuracy loss
Simple Analogy
Removing whole shelves from a warehouse in neat rows so forklifts take shorter paths — not randomly deleting single boxes everywhere.
Common Usage Examples
  • 2:4 sparsity on supported GPUs
  • Channel prune then finetune CNNs
  • Measure real tokens/s not only sparsity %
  • Combine with quantisation
Summary
In short: Structured sparsity removes weights in accelerator-friendly patterns so sparsity becomes real speed, not only smaller files.