zero allication fnv hashing of #golang

hash.go

// https://github.com/golang/go/blob/master/src/hash/fnv/fnv.go#L100 the code we previously  used
// has some allocations
// we need minimum footprint per deciding
func findIndex(s string, poolSize uint32) uint32 {
	var h32a uint32 = 2166136261
	for _, c := range []byte(s) {
		h32a *= 16777619
		h32a ^= uint32(c)
	}
	return h32a % poolSize
}