What problem does it solve? Diagnosing performance bottlenecks in Python scripts, running processes, and GPU workloads requires choosing the right profiling tools and often writing custom instrumentation, which is time-consuming and error-prone. ## Core Features & Use Cases - Multi-target profiling: Profile Python scripts, running processes by PID, specific functions, or entire frameworks like vLLM serving end-to-end. - External tool integration: Uses cProfile, py-spy, tracemalloc, memray, nvidia-smi, torch.profiler, nsys, and NCCL debugging based on the target. - Custom code instrumentation: Writes and inserts timing, memory tracking, and CUDA event code when external tools are insufficient, with a mandatory changelog of all modifications. - Use Case: Ask to profile a multi-GPU training script and receive structured tables covering CPU overhead, memory redundancy, GPU-GPU transfer bandwidth, NCCL collective latency, and ranked optimization recommendations. ## Quick Start Profile my train.py script and identify the GPU and memory bottlenecks.