What latency under load means
During an upload or download, small requests may take longer to return. Data can queue along the path. Excessive queueing is often described as bufferbloat, but a browser test alone cannot locate the queue or prove which device is responsible.
Compare absolute changes
A change from 2 to 7 milliseconds is very different from 80 to 240 milliseconds, even though both are large ratios. Look at the size of the increase, the final response time, and whether the behavior repeats.
Try a repeatable experiment
Use the standard test, note idle and loaded latency, then pause background transfers and repeat. Compare with Ethernet if possible. If the issue repeats, consult the router’s documentation for traffic management or smart queue management options. Change one setting at a time and keep a way to restore it.
Know the limits of this test
Short transfers may finish before enough loaded-latency samples are collected. A missing reading is not evidence that latency is good. Our early version uses conservative explanatory rules rather than a certified bufferbloat grade.