func benchmarkPutObjectPart(b *testing.B, instanceType string, objSize int) {
	// create a temp Erasure/FS backend.
	ctx, cancel := context.WithCancel(context.Background())
	defer cancel()
	objLayer, disks, err := prepareTestBackend(ctx, instanceType)
	if err != nil {
		b.Fatalf("Failed obtaining Temp Backend: <ERROR> %s", err)
	}
	// cleaning up the backend by removing all the directories and files created on function return.

	ctx, cancel := context.WithCancel(context.Background())
	// create an instance of TestServer.
	testServer := TestServer{cancel: cancel}
	// return FS/Erasure object layer and temp backend.
	objLayer, disks, err := prepareTestBackend(ctx, instanceType)
	if err != nil {
		t.Fatal(err)
	}

	// set new server configuration.
	if err = newTestConfig(globalMinioDefaultRegion, objLayer); err != nil {
		t.Fatalf("%s", err)
	}