Internal

Throughput

In general terms, throughput is the rate at which something can be produced, consumed or processed.

Latency and response time are synonymous: the length of time it takes something interesting to happen.

Standard deviation does not have any meaning for a dataset that describes latency. It is not relevant.

Latency must be measured in the context of load, measuring the latency without load is misleading.

Define saturation.

Identify where the saturation point is. Don't run a system at saturation or over.

Response time and service time diverge as saturation becomes worse.

Don't censor bad data, don't throw away data selectively.
Never average percentiles.
Coordinated omission. Coordinate omission usually makes something that you think is a response time metric only represent a service time component.
Response Time in Queueing Theory.
Service Time in Queueing Theory.
xth percentile (quantiles) - the value of the performance parameter at which x% of the request are better; https://www.vividcortex.com/blog/why-percentiles-dont-work-the-way-you-think