Go Runtime Performance

Focus this module

• Benchmark first, then optimize.
• Optimize one variable at a time.
• Keep a baseline before every change.

Allocation control

• -benchmem for alloc counts
• avoid fmt and unnecessary copies in hot paths
• pre-size containers

GC and heap

• GC pressure is about live memory
• prefer lower retained set and smaller pointer graphs
• tune GOGC and GOMEMLIMIT with measured trade-offs

Scheduler

• M/P/G model
• avoid tiny goroutines for tiny work
• bound concurrency for CPU-bound work

Memory model

• define happens-before edges before optimization
• channels, locks, atomics
• immutable snapshots for lock-free reads

Generics

• generics can be faster than expected, but benchmark anyway
• avoid broad constraints and any boxing in hot code

Final workflow

• 1) baseline
• 2) single-target change
• 3) compare before/after
• 4) lock in with regression checks