Go Runtime Internals

• Stack growth is dynamic, not fixed.
• Escape decisions affect GC load.
• Inlining and callgraph shape affect hot-path cost.

GC and scheduler

• Tune with load + benchmarks, not only config knobs.
• sync.Pool is optional caching, not a contract.

Advanced performance checklist

• less allocation
• less live heap
• fewer runnable goroutines
• predictable shutdown and backpressure