roachprod: add --gce-use-spot

Previously, `--gce-preemptible` was available.
This change adds an option to create a GCE spot
instance, whose lifetime can extend 24h; otherwise,
it's essentially equivalent to a GCE preemptible.
VM metadata and billing estimator are updated to
handle both preemptible and spot instances.

Epic: none

Release note: None

pkg/cmd/roachprod/main.go

@@ -326,6 +326,13 @@ hosts file.
 							}
 						}
 						timeRemaining := c.LifetimeRemaining().Round(time.Second)
+						formatTTL := func(ttl time.Duration) string {
+							if c.VMs[0].Preemptible {
+								return color.HiMagentaString(ttl.String())
+							} else {
+								return color.HiBlueString(ttl.String())
+							}
+						}
 						cost := c.CostPerHour
 						totalCostPerHour += cost
 						alive := timeutil.Since(c.CreatedAt).Round(time.Minute)
@@ -336,14 +343,14 @@ hosts file.
 								color.HiGreenString(p.Sprintf("$%.2f", cost)),
 								colorByCostBucket(costSinceCreation)(p.Sprintf("$%.2f", costSinceCreation)),
 								color.HiWhiteString(alive.String()),
-								color.HiBlueString(timeRemaining.String()),
+								formatTTL(timeRemaining),
 								colorByCostBucket(costRemaining)(p.Sprintf("$%.2f", costRemaining)))
 						} else {
 							fmt.Fprintf(tw, "\t%s\t%s\t%s\t%s\t%s\t",
 								color.HiGreenString(""),
 								color.HiGreenString(""),
 								color.HiWhiteString(alive.String()),
-								color.HiBlueString(timeRemaining.String()),
+								formatTTL(timeRemaining),
 								color.HiGreenString(""))
 						}
 					} else {

pkg/roachprod/vm/gce/gcloud.go

@@ -118,6 +118,13 @@ type jsonVM struct {
 			NatIP string
 		}
 	}
+	Scheduling struct {
+		AutomaticRestart          bool
+		Preemptible               bool
+		OnHostMaintenance         string
+		InstanceTerminationAction string
+		ProvisioningModel         string
+	}
 	MachineType string
 	SelfLink    string
 	Zone        string
@@ -155,6 +162,10 @@ func (jsonVM *jsonVM) toVM(
 			vpc = lastComponent(jsonVM.NetworkInterfaces[0].Network)
 		}
 	}
+	if jsonVM.Scheduling.OnHostMaintenance == "" {
+		// N.B. 'onHostMaintenance' is always non-empty, hence its absense implies a parsing error
+		vmErrors = append(vmErrors, vm.ErrBadScheduling)
+	}
 
 	machineType := lastComponent(jsonVM.MachineType)
 	zone := lastComponent(jsonVM.Zone)
@@ -216,6 +227,7 @@ func (jsonVM *jsonVM) toVM(
 		Errors:                 vmErrors,
 		DNS:                    fmt.Sprintf("%s.%s.%s", jsonVM.Name, zone, project),
 		Lifetime:               lifetime,
+		Preemptible:            jsonVM.Scheduling.Preemptible,
 		Labels:                 jsonVM.Labels,
 		PrivateIP:              privateIP,
 		Provider:               ProviderName,
@@ -253,6 +265,7 @@ func DefaultProviderOpts() *ProviderOpts {
 		TerminateOnMigration: false,
 		useSharedUser:        true,
 		preemptible:          false,
+		useSpot:              false,
 	}
 }
 
@@ -283,6 +296,8 @@ type ProviderOpts struct {
 	useSharedUser bool
 	// use preemptible instances
 	preemptible bool
+	// use spot instances (i.e., latest version of preemptibles which can run > 24 hours)
+	useSpot bool
 }
 
 // Provider is the GCE implementation of the vm.Provider interface.
@@ -809,7 +824,10 @@ func (o *ProviderOpts) ConfigureCreateFlags(flags *pflag.FlagSet) {
 			"will be repeated N times. If > 1 zone specified, nodes will be geo-distributed\n"+
 			"regardless of geo (default [%s])",
 			strings.Join(defaultZones, ",")))
-	flags.BoolVar(&o.preemptible, ProviderName+"-preemptible", false, "use preemptible GCE instances")
+	flags.BoolVar(&o.preemptible, ProviderName+"-preemptible", false,
+		"use preemptible GCE instances (lifetime cannot exceed 24h)")
+	flags.BoolVar(&o.useSpot, ProviderName+"-use-spot", false,
+		"use spot GCE instances (like preemptible but lifetime can exceed 24h)")
 	flags.BoolVar(&o.TerminateOnMigration, ProviderName+"-terminateOnMigration", false,
 		"use 'TERMINATE' maintenance policy (for GCE live migrations)")
 }
@@ -956,6 +974,8 @@ func (p *Provider) Create(
 		// Preemptible instances require the following arguments set explicitly
 		args = append(args, "--maintenance-policy", "TERMINATE")
 		args = append(args, "--no-restart-on-failure")
+	} else if providerOpts.useSpot {
+		args = append(args, "--provisioning-model", "SPOT")
 	} else {
 		if providerOpts.TerminateOnMigration {
 			args = append(args, "--maintenance-policy", "TERMINATE")
@@ -1472,6 +1492,7 @@ func populateCostPerHour(l *logger.Logger, vms vm.List) error {
 							},
 						},
 					},
+					Preemptible: vm.Preemptible,
 					MachineType: &cloudbilling.MachineType{
 						PredefinedMachineType: &cloudbilling.PredefinedMachineType{
 							MachineType: machineType,

pkg/roachprod/vm/vm.go

@@ -73,9 +73,10 @@ type VM struct {
 	CreatedAt time.Time `json:"created_at"`
 	// If non-empty, indicates that some or all of the data in the VM instance
 	// is not present or otherwise invalid.
-	Errors   []error           `json:"errors"`
-	Lifetime time.Duration     `json:"lifetime"`
-	Labels   map[string]string `json:"labels"`
+	Errors      []error           `json:"errors"`
+	Lifetime    time.Duration     `json:"lifetime"`
+	Preemptible bool              `json:"preemptible"`
+	Labels      map[string]string `json:"labels"`
 	// The provider-internal DNS name for the VM instance
 	DNS string `json:"dns"`
 	// The name of the cloud provider that hosts the VM instance
@@ -129,9 +130,10 @@ func Name(cluster string, idx int) string {
 
 // Error values for VM.Error
 var (
-	ErrBadNetwork   = errors.New("could not determine network information")
-	ErrInvalidName  = errors.New("invalid VM name")
-	ErrNoExpiration = errors.New("could not determine expiration")
+	ErrBadNetwork    = errors.New("could not determine network information")
+	ErrBadScheduling = errors.New("could not determine scheduling information")
+	ErrInvalidName   = errors.New("invalid VM name")
+	ErrNoExpiration  = errors.New("could not determine expiration")
 )
 
 var regionRE = regexp.MustCompile(`(.*[^-])-?[a-z]$`)