Gemma 4 hits repetition loop in local backends

Gemma 4's deployment friction highlights the technical gap between proprietary cloud stacks and the local inference ecosystem.

• –Infinite repetition in llama.cpp is triggered by PEG parser errors in the chat template, specifically during tool-call generation.
• –The new Multi-Token Prediction (MTP) heads in Gemma 4 31B require more precise handling than previous sequential sampling methods used in local engines.
• –Tokenizer artifacts like "of" hyphenation or merging suggest underlying BPE encoding shifts that local tools have yet to fully optimize for these new architectures.
• –Stability on Vertex AI confirms the weights are robust, shifting the burden of fix to local tool maintainers like the llama.cpp and Ollama communities.
• –Workarounds like disabling parallel tool calls and using specific stable quants (Q3K/Q4K) are currently necessary for reliable workstation performance.