is the latest 1.18 go routine faster than this? just curious coz it seems faster etc now about gopkg

[PureWhiteWu]

No, the function of gopool is not only reuse the goroutine, but also limit the number of goroutine.
For example in CPU-heavy jobs, to limit the number of goroutines can greatly decrease the need to do context switches, and thus improve the performance.
If you change the DoCopyStack depth to 10000 in the gopool_test.go, you may find that gopool is much more faster than native goorutine:

func DoCopyStack(a, b int) int {
	if b < 10000 {
		return DoCopyStack(0, b+1)
	}
	return 0
}

result:

goos: darwin
goarch: arm64
pkg: github.com/bytedance/gopkg/util/gopool
BenchmarkPool-10    	      15	  73215625 ns/op	  234532 B/op	   10071 allocs/op
BenchmarkGo-10      	       2	 579915708 ns/op	  921604 B/op	   11625 allocs/op
PASS
ok  	github.com/bytedance/gopkg/util/gopool	3.923s