A practical guide to understanding how CPU caches (L1/L2/L3) impact Go service performance, with benchmarks on modern hardware.

How CPU word alignment and struct field ordering silently inject memory padding in Go. Learn field reordering to cut heap memory allocations and cache misses.

When thinking about performance, it's easy to focus on Big O notation. But in Go, the difference between the Stack and the Heap is often the difference between a service that scales and one that chokes on GC pauses. This post explores escape analysis, the "Pointer Myth", and why passing by value is often 40x faster than passing by pointer.