Mistral shipped a time-series foundation model today. I measured its latency — and its confidence.
Description and use
Latency scales linearly with thread count; 5M model meets 10 ms claim on 8 threads, but requires ~50 ms on 2 threads. Point forecasts outperform seasonal naive by 37% MAE. Probabilistic intervals are severely under‑covered (17% for 80% band), making them unreliable for alerting without local calibration.
Problem
Assessing the real-world performance of Mistral’s new Timestral time-series foundation models on CPU latency, point forecast accuracy, and probabilistic calibration.
Outcome
Latency scales linearly with thread count; 5M model meets 10 ms claim on 8 threads, but requires ~50 ms on 2 threads. Point forecasts outperform seasonal naive by 37% MAE. Probabilistic intervals are severely under‑covered (17% for 80% band), making them unreliable for alerting without local calibration.
Workflow
- 1. Download Timestral‑5M and Timestral‑28M weights from Hugging Face.
- 2. Verify parameter counts from weight files.
- 3. Run inference on a 2‑vCPU VM with torch pinned to 2 threads, measuring median latency over seven runs.
- 4. Forecast 96 steps ahead from 2,016‑step context (three weeks at 15‑min intervals).
- 5. Compare latency to Mistral’s 8‑thread claim.
- 6. Evaluate point forecast MAE on monthly airline passengers (1949‑1960) against seasonal naive and drift baselines.
- 7. Compute 80% prediction interval coverage and bias over 24‑month hold‑out.
- 8. Analyze quantile monotonicity and interval width growth.
- 9. Summarize findings and recommend capacity planning and calibration checks.
Evidence
On a standard server CPU with 8 threads, forecasting one day ahead from three weeks of 15-minute history takes 10 ms with the 5M model and 140 ms with the 209M model.
model Mistral claim (8 threads) mine, median (2 threads) mine, min Timestral-5M 10 ms 52.4 ms 35.9 ms
MAE (passengers, thousands) Timestral-5M median 44.93 seasonal naive 71.25 drift 91.62
80% interval coverage, 24 months 4 of 24 = 16.7% first 12 months 25.0% last 12 months 8.3% median bias over 24 months -44.93
- Record date: 2026-10-20T00:41:10.854Z