Pointers vs. Structs

pointers.go

package main

import (
	"fmt"
	"time"
)

const (
	GraphSize      = 8
	RecursionDepth = 5
	RecursionWidth = 5
	Iterations     = 100
)

type SubGraph interface{}

type MyGraph struct {
	SG1 SubGraph
	SG2 SubGraph
	SG3 SubGraph
	SG4 SubGraph

	I1 int64
	I2 int64
	I3 int64
	I4 int64
	I5 int64
	I6 int64
	I7 int64
	I8 int64
}

func NewGraph() SubGraph {
	return newSubGraph(GraphSize)
}

func newSubGraph(n int) SubGraph {
	if n == 0 {
		return MyGraph{
			I1: 1,
			I2: 2,
			I3: 3,
			I4: 4,
			I5: 5,
			I6: 6,
			I7: 7,
			I8: 8,
		}
	}

	return MyGraph{
		SG1: newSubGraph(n - 1),
		SG2: newSubGraph(n - 1),
		SG3: newSubGraph(n - 1),
		SG4: newSubGraph(n - 1),
		I1:  1,
		I2:  2,
		I3:  3,
		I4:  4,
		I5:  5,
		I6:  6,
		I7:  7,
		I8:  8,
	}
}

func NewPtrGraph() SubGraph {
	return newPtrSubGraph(GraphSize)
}

func newPtrSubGraph(n int) SubGraph {
	if n == 0 {
		return &MyGraph{
			I1: 1,
			I2: 2,
			I3: 3,
			I4: 4,
			I5: 5,
			I6: 6,
			I7: 7,
			I8: 8,
		}
	}

	return &MyGraph{
		SG1: newPtrSubGraph(n - 1),
		SG2: newPtrSubGraph(n - 1),
		SG3: newPtrSubGraph(n - 1),
		SG4: newPtrSubGraph(n - 1),
		I1:  1,
		I2:  2,
		I3:  3,
		I4:  4,
		I5:  5,
		I6:  6,
		I7:  7,
		I8:  8,
	}
}

func doThingsWith(g SubGraph, n int) bool {
	if n == 0 {
		return true
	}
	result := true
	for x := 0; x < RecursionWidth; x++ {
		result = result && doThingsWith(g, n-1)
	}
	return result
}

func main() {
	start := time.Now()
	for x := 0; x < Iterations; x++ {
		doThingsWith(NewGraph(), RecursionDepth)
	}
	end := time.Now()
	fmt.Printf("Non-Pointer: %v\n", end.Sub(start))

	start = time.Now()
	for x := 0; x < Iterations; x++ {
		doThingsWith(NewPtrGraph(), RecursionDepth)
	}
	end = time.Now()

	fmt.Printf("Pointer: %v\n", end.Sub(start))
}