Why a busy speech GPU felt slower

A fast isolated encoder does not guarantee a responsive shared service. I tested ASR, embeddings and speech synthesis together on the RTX 3060 and retained failures and health checks.

From isolated speed to shared traffic

A fast isolated encoder does not guarantee a responsive shared service. I tested ASR, embeddings and speech synthesis together on the RTX 3060 and retained failures and health checks.

The follow-up completed 9,407 requests across 24 phases. At mixed concurrency one, median ASR latency was about 240 ms, embeddings 48 ms and synthesis 234 ms. Their isolated observations were about 61, 25 and 118 ms.

More parallel work had a cost

At concurrency four, ASR latency reached 1,131 ms. ASR throughput was 34.6 times real time, below the 41.6 observed at mixed concurrency one. The phases lasted fifteen seconds with two repeats, so they describe a deliberately busy service rather than representative user traffic.

A separate bottleneck audit retained 4,044 requests and 1,671 health checks. These observations support resource contention as an operational issue; they do not prove that every slowdown came from one component.

The deployment lesson

Choose concurrency using both latency and throughput. Admission control and separate load budgets deserve a direct test before treating a benchmark maximum as a production setting.

Evidence and publication boundary

This is an edited account of the recorded experiment. The linked archive is private; the methods, aggregate findings and limits are included above. Reference recordings, raw conversations, authentication material and workstation configuration are excluded.