The Transport pool was rewritten around a per-target clientConnPoolEntry with a channel-based lock, keeps two idle connections per host by default, and only recycles a connection …
Go’s write barrier records both the old and the new value of every pointer slot into a per-P buffer, and the flush greys both — a Yuasa deletion barrier plus a Dijkstra insertion …
The Go inliner charges one unit per IR node against a budget of 80, rejects defer/go/tailcall outright, and with a PGO profile it will inline hot call sites costing up to 2000.
Interfaces are two machine words, the itab is usually emitted statically by the compiler, and the runtime keeps a lock-protected hash table for the cases it cannot know.
The Go linker flood-fills symbols from main.main, prunes type method tables unless an interface or reflection can reach them, and drops DWARF and the symbol table with -ldflags=-w …