Jingchao Zhang, PhD

20 Apr 2026

Decoding Azure’s NCCL Topology Files

Introduction Spin up an Standard_ND96isr_H100_v5 VM on Azure, poke around /opt/microsoft/, and you’ll find a curious...

24 Mar 2026

Gang Scheduling on AKS: Volcano vs Kueue vs KAI Scheduler

Introduction

23 Mar 2026

GPU Fault Detection with NVSentinel on Azure AKS

Introduction

22 Mar 2026

Visualizing Dense and MoE Models IB Communication

TL;DR — I captured per-port, 10-millisecond resolution InfiniBand traffic during FSDP fine-tuning of Qwen-7B (dense) ...

18 Mar 2026

Three VMSS Uniform Settings for HPC/AI Users

If you deploy GPU VMs on Azure using VMSS Uniform mode, three settings can make the difference between a successful a...

17 Mar 2026

Experiments on NCCL Ring vs Tree

We implement a ring allreduce algorithm from scratch in Python, run it on 16 NVIDIA H100 GPUs across 2 nodes with Inf...