LLM Training: The End-to-End Flow

What each step of an LLM training iteration computes, what it costs in memory and arithmetic, and where the loop stalls on real hardware.

August 10, 2026 · 19 min · Sandeep Kumar

Tiling and Collective Operations

The two data-movement primitives behind training performance: tiling inside a device, collectives between devices.

August 12, 2026 · 17 min · Sandeep Kumar

PyTorch Distributed Training Internals

The mechanism behind step 5 of the training loop: bucketed gradient all-reduce triggered from autograd hooks, what NCCL does with it, and how to diagnose the result.

August 12, 2026 · 13 min · Sandeep Kumar

Activations, Normalization and Optimizers, in Plain Terms

What each of the standard building blocks actually does, why it replaced the thing before it, and what it costs.

August 12, 2026 · 10 min · Sandeep Kumar