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Performance ​

Performance defines the amount of useful work accomplished by a system. As a quality attribute, we want to response to an event arriving within some time constraint.

Scenario ​

  • Source: external, internal
  • Stimulus: event arrival pattern (fixed frequency, probability, random)
  • Artifact: system services
  • Environment: normal, overload
  • Response: change operation mode ?
  • Measure: latency, deadline, throughput, miss rate, data loss

Example ​

Performance on crossing gate controller

  • Source: external (arriving train)
  • Stimulus:
  • Artifact: system services
  • Environment: normal, overload
  • Response: change operation mode ?
  • Measure: latency, deadline, throughput, miss rate, data loss

Tactics ​

Resources examples: CPU, RAM, storage, network, etc.

Resource Demand ​

  • Relevant algorithms
  • Threading / multi-threading / parallelism
  • Reduce data (size, frequency)
  • Reduce code, refactoring

Resource management ​

  • Concurrency (horizontal scaling)
  • Maintain copies (e.g. system state)
  • Allocation according to task
  • Arbitration among components