Tagged “kernels”

3 posts.

All Model Architecture19 Training & Alignment22 Inference & Serving18 Agents & Orchestration11 Reasoning & Evaluation26 Safety, Security & Governance7 Platforms & Practice20

Inference & Serving 29 min

Arithmetic Intensity: Why Your GPU Is Idle 99% of the Time

An H100 advertises 989 teraflops. Generating one token from an 8B model uses roughly 0.3% of that. The gap is not a bug in your code or a missing compiler flag; it is a single ratio, FLOPs per byte moved, and almost every perform…

neural-plumbing gpu performance kernels ∑ ◫

Inference & Serving 21 min

FlashAttention and the Memory Wall: Why Attention Was Never Compute-Bound

An A100 can execute 312 trillion half-precision operations per second but can only pull about 2 terabytes from memory in that same second. FlashAttention made attention fast not by computing less, but by refusing to touch memory.

flashattention gpu attention transformers ∑ ◫

Inference & Serving 24 min

Your Answer Depends on Who Else Is in the Batch

A thousand identical requests to the same model at temperature zero produced eighty different completions. The cause is not random seeds, not sampling, and not GPU atomics. It is that reduction kernels change their summation orde…

inference determinism numerics kernels ∑ ◫