概念概述
超越设计极限的压力测试（Stress Testing Beyond Design Limits）指的是：压力测试把系统推到预期容量之上，找出崩溃点并观察其失败与恢复方式，而不仅仅是是否达标。
从更严格的定义看，Stress testing is a performance test that intentionally exceeds normal or peak load to determine the system’s limits and the manner in which it degrades or collapses. 该概念在工程实践中的价值，在于它能帮助团队用统一的语言描述一个具体的质量属性或设计约束，从而在评审与协作中减少歧义。
为什么需要它
It is used before major launches to understand failure modes, recovery behaviour, and the load at which resource exhaustion begins. 它与 Load Testing to Target Concurrency、Approval Testing、Test Parallelization and Sharding 等概念经常一起出现，用于解决相近的工程问题。理解它的适用场景，有助于在多种备选方案之间做出有依据的取舍，而不是凭直觉选择技术方案。
常见误解
- stress testing is the same as load testing
- a passing stress test means the system will never fail
需要避免的反模式
- running unlimited stress without monitoring internal resource saturation
- testing only the steady state and never the recovery after overload
实践要点
- Where load testing confirms a target throughput, stress testing climbs until an error rate or latency blows up, revealing the true ceiling and the first bottleneck.
- Observing which resource saturates first, whether CPU, memory, connections, or a dependency, turns the result into an actionable capacity plan.
- The recovery phase matters as much as the peak, because a system that fails gracefully and sheds load is very different from one that collapses and cannot restart.