CPU Performance Under Load

This feature thread tracks the evolution of understanding and optimizing system performance under varying CPU utilization. Initially, the focus was on observing the correlation between high CPU utilization and increased latency. This post details experiments using the Large Unicorn Collider (LUC) environment to measure CPU time per request and latency percentage increases across different instance types as CPU utilization rises. It explores the impact of CPU frequency changes due to Turbo Boost, the effect of Hyper-Threading, and the identification of an optimal CPU utilization threshold (the "Golden Ratio") to balance efficiency and performance. An outlier case involving a disabled CPU C-state and its resolution is also discussed, leading to more consistent performance across instances.