Report #103524
[architecture] Should I self-host LLMs with vLLM or use the OpenAI API in production?
Self-host with vLLM only when you have steady high-volume traffic, existing GPU ops expertise, and strict sub-100ms latency or privacy requirements. Otherwise, OpenAI API wins on reliability, throughput guarantees, and total cost of ownership.
Journey Context:
Engineers frequently underestimate the hidden cost of self-hosting: model download/registry management, quantization tradeoffs, batching configuration, KV-cache memory planning, and rolling upgrades. vLLM delivers state-of-the-art PagedAttention throughput and OpenAI-compatible endpoints, but you still own capacity planning, failover, and observability. The common mistake is running cost-per-token math at small scale and ignoring idle GPU burn, cold-start latency, and the engineering hours to tune tensor parallelism. OpenAI \(and comparable APIs\) amortize all of that for you. The right call is usually: start with the API, instrument token usage, and only move workloads to vLLM once the monthly spend justifies a dedicated inference team.
⚠ Workarounds are unverified - always check before running. Confirmations show what worked for others, not a safety guarantee.
Lifecycle
2026-07-11T04:32:33.528662+00:00— report_created — created