vm: make rosetta emulation configurable

cmd/start.go

@@ -146,6 +146,9 @@ func init() {
 	}
 	if util.MacOS13OrNewer() {
 		startCmd.Flags().StringVarP(&startCmdArgs.VMType, "vm-type", "t", defaultVMType, "virtual machine type ("+types+")")
+		if util.MacOS13OrNewerOnM1() {
+			startCmd.Flags().BoolVar(&startCmdArgs.VZRosetta, "vz-rosetta", false, "enable Rosetta for amd64 emulation")
+		}
 	}
 
 	// config
@@ -221,7 +224,10 @@ func mountsFromFlag(mounts []string) []config.Mount {
 }
 
 func setDefaults(cmd *cobra.Command) {
-	startCmdArgs.VMType = "qemu"
+	if startCmdArgs.VMType == "" {
+		startCmdArgs.VMType = "qemu"
+	}
+
 	if util.MacOS13OrNewer() {
 		// changing to vz implies changing mount type to virtiofs
 		if cmd.Flag("vm-type").Changed && startCmdArgs.VMType == "vz" && !cmd.Flag("mount-type").Changed {
@@ -364,6 +370,11 @@ func prepareConfig(cmd *cobra.Command) {
 				startCmdArgs.VMType = current.VMType
 			}
 		}
+		if util.MacOS13OrNewerOnM1() {
+			if !cmd.Flag("vz-rosetta").Changed {
+				startCmdArgs.VZRosetta = current.VZRosetta
+			}
+		}
 	}
 }
 

config/config.go

@@ -79,8 +79,9 @@ type Config struct {
 	Network      Network           `yaml:"network,omitempty"`
 	Env          map[string]string `yaml:"env,omitempty"` // environment variables
 
-	// VM VMType
-	VMType string `yaml:"vmType,omitempty"`
+	// VM
+	VMType    string `yaml:"vmType,omitempty"`
+	VZRosetta bool   `yaml:"rosetta,omitempty"`
 
 	// volume mounts
 	Mounts    []Mount `yaml:"mounts,omitempty"`

embedded/defaults/colima.yaml

@@ -113,6 +113,10 @@ docker: {}
 # Default: qemu
 vmType: qemu
 
+# Utilise rosetta for amd64 emulation (requires m1 mac and vmType `vz`)
+# Default: false
+rosetta: false
+
 # Volume mount driver for the virtual machine (virtiofs, 9p, sshfs).
 #
 # virtiofs is limited to macOS and vmType `vz`. It is the fastest of the options.

environment/vm/lima/yaml.go

@@ -35,12 +35,12 @@ func newConf(ctx context.Context, conf config.Config) (l Config, err error) {
 		l.VMType = VZ
 
 		// Rosetta is only available on M1
-		if l.Arch == environment.AARCH64 {
+		if conf.VZRosetta && util.MacOS13OrNewerOnM1() {
 			if util.RosettaRunning() {
 				l.Rosetta.Enabled = true
 				l.Rosetta.BinFmt = true
 			} else {
-				logrus.Warnln("Rosetta2 is not installed, linux/amd64 containers will run much slower")
+				logrus.Warnln("Unable to enable Rosetta: Rosetta2 is not installed")
 				logrus.Warnln("Run 'softwareupdate --install-rosetta' to install Rosetta2")
 			}
 		}

util/util.go

@@ -30,6 +30,11 @@ func MacOS() bool {
 	return runtime.GOOS == "darwin"
 }
 
+// MacOS13OrNewer returns if the current OS is macOS 13 or newer.
+func MacOS13OrNewerOnM1() bool {
+	return runtime.GOARCH == "arm64" && MacOS13OrNewer()
+}
+
 // MacOS13OrNewer returns if the current OS is macOS 13 or newer.
 func MacOS13OrNewer() bool {
 	if !MacOS() {