SemiAnalysis: TTFT Overrated? The Real Bottleneck in Large Model Inference Lies in Balancing Interactivity and Throughput

Odaily News, SemiAnalysis published an article stating that the commonly cited "time-to-first-token" (TTFT) in large model inference may be overemphasized by the market. The core dimension of an inference system is not simply "faster is better," but rather a trade-off between "single-user interaction speed (tok/s/user)" and "overall throughput efficiency (tok/s/GPU)." In most scenarios, TTFT has a limited impact on user experience, while the token generation speed is the key variable.

SemiAnalysis concludes that only about 10%–20% of inference tasks are truly latency-bound, while the majority of other scenarios rely more on optimizing throughput and cost efficiency.