What problem does it solve?
This skill helps diagnose difficult SGLang CUDA failures such as illegal memory access, device-side assertions, out-of-bounds errors, NaNs, Infs, and out-of-memory crashes by capturing kernel inputs and execution context before the process fails.
Core Features & Use Cases
- Kernel Boundary Logging: Enable API logging for custom operations, attention, linear, quantization, rotary, and diffusion entry points.
- Progressive Diagnostics: Select logging levels that expose function names, tensor metadata, numerical statistics, or crash-safe tensor dumps.
- Crash Reproduction: Build minimal LLM and diffusion reproducers for validating CUDA failure behavior.
- Distributed Debugging: Separate logs and dump directories across multiple GPU worker processes.
- Advanced Investigation: Combine captured inputs with compute-sanitizer, cuda-gdb, CUDA synchronization, and device-side printf debugging.
- Use Case: When an SGLang model encounters a device-side assertion, use level-3 or level-10 logging to identify the last failing API boundary and inspect tensor shapes, devices, dtypes, and values.
Quick Start
Ask the skill to configure SGLang kernel API logging for a reproducible CUDA crash and identify the likely failing tensor or kernel boundary.