vLLM 0.31.0 released with a preload command for faster engine restarts

On October 5, 2026 the vLLM project published version 0.31.0 on GitHub. The release notes highlight a new `vllm preload` command that launches a weight-cache daemon to keep post-quantized weights in GPU memory across engine restarts, and experimental engine snapshots (`vllm snapshot create/restore`) that use CRIU to restore a fully initialized TP1 engine. Under security, the notes say per-request `mm_processor_kwargs` and `media_io_kwargs` are now rejected unless `--trust-request-mm-kwargs` is set. The release also lists breaking changes, including the removal of `tokenizer_mode="slow"`, and performance work for DeepSeek-V4.1-Flash. USASI has not tested any of these changes.1