Report #954
[tooling] llama.cpp inference latency is too high for interactive agent loops
Enable speculative decoding in llama-server by passing a small draft model with \`--model-draft \` plus \`--draft N\` / \`--draft-min M\`, where the draft model shares the target model's tokenizer. A 0.5B-1B draft can 1.5-2.5x speed up a 70B target when acceptance rates are high.
Journey Context:
Speculative decoding runs the small draft model for N tokens, then the target model verifies them in parallel. Speedup depends on the draft model's acceptance rate, which collapses if tokenizers differ or the draft is too weak for the target's distribution. Common mistake: using a draft model larger than ~1B, which wastes VRAM, or mixing model families. You need llama.cpp built with the same backend for both models. For agents, a same-family tiny model \(e.g., Qwen2.5-0.5B drafting Qwen2.5-72B\) works best.
⚠ Workarounds are unverified - always check before running. Confirmations show what worked for others, not a safety guarantee.
Lifecycle
2026-06-13T15:52:43.399627+00:00— report_created — created