Hackathon/cluster (grafana#3931)

* [wip] jsonnets upport

* jsonnet templating

cmd/cluster-plan/main.go

@@ -15,6 +15,9 @@ type Config struct {
 	DaysRetention   int
 	MonthlyUnitCost sizing.UnitCostInfo
 	Simple          bool
+
+	// Templating
+	Template string
 }
 
 func (c *Config) RegisterFlags(f *flag.FlagSet) {
@@ -25,6 +28,9 @@ func (c *Config) RegisterFlags(f *flag.FlagSet) {
 	f.Float64Var(&c.MonthlyUnitCost.CostPerGBDisk, "monthly-cost-per-gb-disk", 0.187, "Monthly dollar cost for a GB of persistent disk")
 	f.Float64Var(&c.MonthlyUnitCost.CostPerGBObjStorage, "monthly-cost-per-gb-obj-storage", 0.023, "Monthly dollar cost for a GB of object storage")
 	f.BoolVar(&c.Simple, "simple", false, "Show a simpler compromise between resource minimums and ceilings.")
+
+	// Templating
+	f.StringVar(&c.Template, "template", "", "choses a template style to write cluster information to stdout instead of the text cluster plan")
 }
 
 func (c *Config) Validate() error {
@@ -53,6 +59,10 @@ func (c *Config) Validate() error {
 		return errors.New("Cannot specify negative cost per GB Object Storage")
 	}
 
+	if c.Template != "" && Templaters[c.Template] == nil {
+		return fmt.Errorf("unexpected template: %s", c.Template)
+	}
+
 	return nil
 }
 
@@ -66,6 +76,12 @@ func main() {
 
 	cluster := sizing.SizeCluster(cfg.BytesPerSecond.Val())
 
+	if cfg.Template != "" {
+		out := Templaters[cfg.Template].Template(cluster)
+		fmt.Print(out)
+		return
+	}
+
 	printClusterArchitecture(&cluster, &cfg, true)
 }
 

cmd/cluster-plan/template.go

@@ -0,0 +1,115 @@
+package main
+
+import (
+	"fmt"
+	"strings"
+
+	"github.com/grafana/loki/pkg/sizing"
+)
+
+var Templaters = map[string]Templater{
+	"jsonnet": JsonnetTemplater{},
+}
+
+type Templater interface {
+	Template(sizing.ClusterResources) string
+}
+
+type JsonnetTemplater struct{}
+
+func (t JsonnetTemplater) Template(cluster sizing.ClusterResources) string {
+	var sb strings.Builder
+	sb.WriteString(
+		`local k = import 'ksonnet-util/kausal.libsonnet';
+local deployment = k.apps.v1.deployment;
+local statefulSet = k.apps.v1.statefulSet;
+{
+`)
+
+	for _, c := range cluster.Components() {
+		sb.WriteString(t.overrides(c))
+	}
+
+	sb.WriteString("}")
+
+	return sb.String()
+}
+
+func (t JsonnetTemplater) overrides(component *sizing.ComponentDescription) string {
+	switch component.Name {
+	case sizing.Distributor:
+		return deploymentOverrides(component, "distributor")
+	case sizing.Ingester:
+		return statefulsetOverrides(component, "ingester")
+	case sizing.Querier:
+		return deploymentOverrides(component, "querier")
+	case sizing.QueryFrontend:
+		return deploymentOverrides(component, "query_frontend")
+	case sizing.Ruler:
+		return deploymentOverrides(component, "ruler")
+	case sizing.Compactor:
+		return statefulsetOverrides(component, "compactor")
+	case sizing.ChunksCache:
+		return memcachedOverrides(component, "chunks")
+	case sizing.QueryResultsCache:
+		return memcachedOverrides(component, "frontend")
+	case sizing.IndexCache:
+		return memcachedOverrides(component, "index_queries")
+	case sizing.IndexGateway:
+		return statefulsetOverrides(component, "index_gateway")
+	default:
+		return ""
+	}
+}
+
+func deploymentOverrides(component *sizing.ComponentDescription, id string) string {
+	return fmt.Sprintf(`
+  %s_deployment+:
+    deployment.mixin.spec.withReplicas(%d),
+
+  %s_container+::
+    k.util.resourcesRequests('%s', '%s') +
+    k.util.resourcesLimits('%s', '%s'),
+`,
+		id,
+		component.Replicas,
+		id,
+		component.Resources.CPURequests.Kubernetes(),
+		sizing.ReadableBytes(component.Resources.MemoryRequests).Kubernetes(),
+		component.Resources.CPULimits.Kubernetes(),
+		sizing.ReadableBytes(component.Resources.MemoryLimits).Kubernetes(),
+	)
+}
+
+func statefulsetOverrides(component *sizing.ComponentDescription, id string) string {
+	return fmt.Sprintf(`
+  %s_statefulset+:
+    statefulSet.mixin.spec.withReplicas(%d),
+
+  %s_container+::
+    $.util.resourcesRequests('%s', '%s') +
+    $.util.resourcesLimits('%s', '%s'),
+`,
+		id,
+		component.Replicas,
+		id,
+		component.Resources.CPURequests.Kubernetes(),
+		sizing.ReadableBytes(component.Resources.MemoryRequests).Kubernetes(),
+		component.Resources.CPULimits.Kubernetes(),
+		sizing.ReadableBytes(component.Resources.MemoryLimits).Kubernetes(),
+	)
+}
+
+func memcachedOverrides(component *sizing.ComponentDescription, id string) string {
+	// Everything but replicas are actually managed by the memcached jsonnet library
+	// and our memcached limits are derived from these, so avoid the complexity of trying to override it.
+	return fmt.Sprintf(`
+  memcached_%s+: {
+    statefulSet+:
+      statefulSet.mixin.spec.withReplicas(%d),
+  },
+`,
+		id,
+		component.Replicas,
+	)
+}

pkg/sizing/cpu.go

@@ -70,3 +70,34 @@ func (b ReadableBytes) String() string {
 	}
 	return fmt.Sprintf("%.2f%s", x, order[degree])
 }
+
+const (
+	B  ReadableBytes = 1
+	KB               = B << 10
+	MB               = KB << 10
+	GB               = MB << 10
+	TB               = GB << 10
+	PB               = TB << 10
+	EB               = PB << 10
+)
+
+func (b ReadableBytes) Kubernetes() string {
+	switch {
+	case b == 0:
+		return "0B"
+	case b%EB == 0:
+		return fmt.Sprintf("%dEi", b/EB)
+	case b%PB == 0:
+		return fmt.Sprintf("%dPi", b/PB)
+	case b%TB == 0:
+		return fmt.Sprintf("%dTi", b/TB)
+	case b%GB == 0:
+		return fmt.Sprintf("%dGi", b/GB)
+	case b%MB == 0:
+		return fmt.Sprintf("%dMi", b/MB)
+	case b%KB == 0:
+		return fmt.Sprintf("%dKi", b/KB)
+	default:
+		return fmt.Sprintf("%dB", b)
+	}
+}

pkg/sizing/sizing.go

@@ -56,10 +56,10 @@ func distributorSizing(ingestionRateMB float64) *ComponentDescription {
 
 	component.Name = Distributor
 	component.Replicas = n
-	_ = component.Resources.MemoryRequests.Set("500KB")
+	_ = component.Resources.MemoryRequests.Set("500MB")
 	_ = component.Resources.MemoryLimits.Set("1GB")
 	component.Resources.CPURequests.SetCores(0.5)
-	component.Resources.CPULimits.SetCores(0.5)
+	component.Resources.CPULimits.SetCores(1)
 	return component
 }