Qwen3.8 27B

User reports Qwen3.8 27B at 23.03 t/s generation and 2248.6 t/s prompt processing on a single RTX 4090 with 32 GB RAM. Setup is llama.cpp via llama-swap with the unsloth UD Q4_K_XL GGUF, a Q8 KV cache, 131072 context, and a BF16 mmproj for multimodal input; cache reuse is disabled because of the multimodal model. The user ran a three-day coding session in VS Code Copilot and hit a failure where the model emitted never-ending slashes; they ask what could cause it.