Performance Concepts: Difference between revisions

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


=Queueing Theory=
=Queueing Theory=

Revision as of 21:23, 2 November 2016

Internal

Throughput

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

Latency

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.

Queueing Theory

https://en.wikipedia.org/wiki/Queueing_theory

  • Response Time in Queueing Theory.
  • Service Time in Queueing Theory.

Response time and service time diverge as saturation becomes worse.

Organizatorium

  • 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.