← All resources

What happens when a GPU writes memory

Auto-discovered

Blog Advanced

Fergus Finn

Visit resource ↗

Description

What happens when a GPU writes memory is Fergus Finn's Doubleword blog follow-up that traces a single STG.E global store on an RTX 4090 through SM execution, the memory coalescer, L1, TLB, crossbar, L2, and DRAM. The article complements Finn's earlier LDG.E load walkthrough with cycle-level timing discussion and experiments on store-path behavior.

Finn uses microbenchmark-style reasoning to show how warp-wide stores interact with caching hierarchies and why naive assumptions about uniform latency fail. Diagrams and measured timelines anchor abstract pipeline slides to a concrete SASS instruction readers can disassemble in profiling tools.

The post suits advanced GPU programmers comfortable with CUDA occupancy basics and memory hierarchy vocabulary. Prior reading of Finn's load article or similar microarchitecture blogs helps, because the narrative references shared experimental setup across the series.

Finn's Doubleword microarchitecture posts are frequently shared among CUDA engineers learning how Ampere and Ada store paths differ from textbook memory models.