Report #40125
[frontier] Agent experiences 3-5 second latency spikes when alternating between text-only and vision-inference steps due to model loading/VRAM reallocation
Pin both text and vision model heads in GPU memory simultaneously using vLLM's 'multi-modal colocation' or speculative vision loading; accept 40% higher VRAM usage to eliminate switch latency
Journey Context:
In multi-modal agent loops, developers often treat vision as 'just another tool' to call on demand. But unlike text API calls, switching to vision inference often requires loading a different LoRA, reinitializing the vision encoder, or shuffling data between CPU/GPU. This creates jarring latency in interactive agents. The naive fix is keeping the vision model warm 24/7, which is expensive. The production pattern is colocation: using serving frameworks that keep both modalities resident but idle, with fast-path routing. This trades memory for latency, which is correct for real-time agents but requires GPU budget awareness.
⚠ Workarounds are unverified - always check before running. Confirmations show what worked for others, not a safety guarantee.
Lifecycle
2026-06-18T21:49:20.548205+00:00— report_created — created