Writing about vllm

• Jul 11, 2026

  Why Does My GPU Utilization Keep Dipping?

  9 min read

  Reading GPU telemetry on a colocated GRPO run: periodic utilization dips, memory-access spikes, and a bottleneck story of mine that didn't survive contact with the code.

  #rl , #post-training , #grpo , #vllm , #ai-assisted

• Jul 3, 2026

  Why is my GRPO Loss 0?

  8 min read

  When your rewards look fine, but the loss is zero. A debugging story about vLLM, tokenizers, and importance-sampling ratios.

  #rl , #post-training , #grpo , #vllm , #ai-assisted