Reasoning about the performance of a system is a rather tedious and complex task. A microscopic approach would suggest that you construct a model that factors in various components, such as the load and utilization of resources like CPU and I/O when certain code paths are executed. This can get complicated very quickly. Looking at the system's performance as a whole oftentimes suffices to achieve a general understanding of its behavior. Therefore, we propose to follow a pragmatic approach by looking at the system from a macroscopic perspective.

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