Add tier-based resource governance via Kyverno [ci skip]

Four layers of noisy-neighbor protection using existing tier system:
- PriorityClasses (tier-0-core through tier-4-aux)
- LimitRange defaults auto-generated per namespace tier
- ResourceQuotas auto-generated per namespace tier
- PriorityClassName injection on pods via Kyverno mutate

Custom quota overrides for monitoring and crowdsec namespaces
which exceed the default tier quotas.
This commit is contained in:
Viktor Barzin 2026-02-15 18:48:33 +00:00
parent 2bae6ccce3
commit 4d9b8242e8
4 changed files with 789 additions and 2 deletions

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@ -410,6 +410,25 @@ jellyfin, jellyseerr, tdarr, affine, health, family
- **3-edge**: User-facing services
- **4-aux**: Optional/auxiliary services
### Resource Governance (Kyverno-based)
Four layers of noisy-neighbor protection, all defined in `modules/kubernetes/kyverno/resource-governance.tf`:
1. **PriorityClasses**: `tier-0-core` (1M) through `tier-4-aux` (200K). `tier-4-aux` uses `preemption_policy=Never`.
2. **LimitRange defaults** (Kyverno generate): Auto-creates `tier-defaults` LimitRange in namespaces based on tier label. Only affects containers without explicit resources.
3. **ResourceQuotas** (Kyverno generate): Auto-creates `tier-quota` ResourceQuota in namespaces with tier labels. Excludes namespaces with `resource-governance/custom-quota=true` label.
4. **Priority injection** (Kyverno mutate): Sets `priorityClassName` on Pods based on namespace tier label.
**Custom quota override**: Add label `resource-governance/custom-quota: "true"` to namespace, then define a custom `kubernetes_resource_quota` in the service's Terraform module. Currently used by: monitoring, crowdsec.
**LimitRange defaults by tier**:
| Tier | Default Req | Default Limit | Max |
|------|------------|--------------|-----|
| 0-core | 100m/128Mi | 2/4Gi | 8/16Gi |
| 1-cluster | 100m/128Mi | 2/4Gi | 4/8Gi |
| 2-gpu | 100m/256Mi | 4/8Gi | 8/16Gi |
| 3-edge | 50m/128Mi | 1/2Gi | 4/8Gi |
| 4-aux | 25m/64Mi | 500m/1Gi | 2/4Gi |
---
## User Preferences

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@ -19,7 +19,8 @@ resource "kubernetes_namespace" "crowdsec" {
metadata {
name = "crowdsec"
labels = {
tier = var.tier
tier = var.tier
"resource-governance/custom-quota" = "true"
}
}
}
@ -332,3 +333,20 @@ resource "kubernetes_role_binding" "blocklist_import" {
}
}
# Custom ResourceQuota for CrowdSec needs more than default 1-cluster quota
# because it runs DaemonSet agents (1 per worker node) + 3 LAPI replicas + web UI
resource "kubernetes_resource_quota" "crowdsec" {
metadata {
name = "crowdsec-quota"
namespace = kubernetes_namespace.crowdsec.metadata[0].name
}
spec {
hard = {
"requests.cpu" = "8"
"requests.memory" = "8Gi"
"limits.cpu" = "16"
"limits.memory" = "16Gi"
pods = "30"
}
}
}

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@ -0,0 +1,732 @@
# =============================================================================
# Tier-Based Resource Governance
# =============================================================================
# Four layers of protection against noisy neighbor issues:
# 1. PriorityClasses - critical services survive resource pressure
# 2. LimitRange defaults (Kyverno generate) - auto-inject defaults for containers without resources
# 3. ResourceQuotas (Kyverno generate) - hard ceiling on namespace resource consumption
# 4. Priority injection (Kyverno mutate) - set priorityClassName based on namespace tier label
# -----------------------------------------------------------------------------
# Layer 1: PriorityClasses
# -----------------------------------------------------------------------------
# Values stay well below system-cluster-critical (2,000,000,000)
resource "kubernetes_priority_class" "tier_0_core" {
metadata {
name = "tier-0-core"
}
value = 1000000
global_default = false
preemption_policy = "PreemptLowerPriority"
description = "Critical infrastructure: ingress, DNS, VPN, auth, monitoring"
}
resource "kubernetes_priority_class" "tier_1_cluster" {
metadata {
name = "tier-1-cluster"
}
value = 800000
global_default = false
preemption_policy = "PreemptLowerPriority"
description = "Cluster services: Redis, metrics, security"
}
resource "kubernetes_priority_class" "tier_2_gpu" {
metadata {
name = "tier-2-gpu"
}
value = 600000
global_default = false
preemption_policy = "PreemptLowerPriority"
description = "GPU workloads: Immich, Ollama, Frigate"
}
resource "kubernetes_priority_class" "tier_3_edge" {
metadata {
name = "tier-3-edge"
}
value = 400000
global_default = false
preemption_policy = "PreemptLowerPriority"
description = "User-facing services: mail, file sync, dashboards"
}
resource "kubernetes_priority_class" "tier_4_aux" {
metadata {
name = "tier-4-aux"
}
value = 200000
global_default = false
preemption_policy = "Never"
description = "Optional services: blogs, tools, experiments. Will not preempt other aux services."
}
# -----------------------------------------------------------------------------
# Layer 2: LimitRange Defaults (Kyverno Generate)
# -----------------------------------------------------------------------------
# Creates a LimitRange in each namespace based on its tier label.
# Only affects containers WITHOUT explicit resource requests/limits.
resource "kubernetes_manifest" "generate_limitrange_by_tier" {
manifest = {
apiVersion = "kyverno.io/v1"
kind = "ClusterPolicy"
metadata = {
name = "generate-limitrange-by-tier"
annotations = {
"policies.kyverno.io/title" = "Generate LimitRange by Tier"
"policies.kyverno.io/description" = "Creates tier-appropriate LimitRange defaults in namespaces based on their tier label. Only affects containers without explicit resource specifications."
}
}
spec = {
generateExisting = true
rules = [
# Tier 0-core
{
name = "limitrange-tier-0-core"
match = {
any = [
{
resources = {
kinds = ["Namespace"]
selector = {
matchLabels = {
tier = "0-core"
}
}
}
}
]
}
generate = {
synchronize = true
apiVersion = "v1"
kind = "LimitRange"
name = "tier-defaults"
namespace = "{{request.object.metadata.name}}"
data = {
spec = {
limits = [
{
type = "Container"
default = {
cpu = "2"
memory = "4Gi"
}
defaultRequest = {
cpu = "100m"
memory = "128Mi"
}
max = {
cpu = "8"
memory = "16Gi"
}
}
]
}
}
}
},
# Tier 1-cluster
{
name = "limitrange-tier-1-cluster"
match = {
any = [
{
resources = {
kinds = ["Namespace"]
selector = {
matchLabels = {
tier = "1-cluster"
}
}
}
}
]
}
generate = {
synchronize = true
apiVersion = "v1"
kind = "LimitRange"
name = "tier-defaults"
namespace = "{{request.object.metadata.name}}"
data = {
spec = {
limits = [
{
type = "Container"
default = {
cpu = "2"
memory = "4Gi"
}
defaultRequest = {
cpu = "100m"
memory = "128Mi"
}
max = {
cpu = "4"
memory = "8Gi"
}
}
]
}
}
}
},
# Tier 2-gpu
{
name = "limitrange-tier-2-gpu"
match = {
any = [
{
resources = {
kinds = ["Namespace"]
selector = {
matchLabels = {
tier = "2-gpu"
}
}
}
}
]
}
generate = {
synchronize = true
apiVersion = "v1"
kind = "LimitRange"
name = "tier-defaults"
namespace = "{{request.object.metadata.name}}"
data = {
spec = {
limits = [
{
type = "Container"
default = {
cpu = "4"
memory = "8Gi"
}
defaultRequest = {
cpu = "100m"
memory = "256Mi"
}
max = {
cpu = "8"
memory = "16Gi"
}
}
]
}
}
}
},
# Tier 3-edge
{
name = "limitrange-tier-3-edge"
match = {
any = [
{
resources = {
kinds = ["Namespace"]
selector = {
matchLabels = {
tier = "3-edge"
}
}
}
}
]
}
generate = {
synchronize = true
apiVersion = "v1"
kind = "LimitRange"
name = "tier-defaults"
namespace = "{{request.object.metadata.name}}"
data = {
spec = {
limits = [
{
type = "Container"
default = {
cpu = "1"
memory = "2Gi"
}
defaultRequest = {
cpu = "50m"
memory = "128Mi"
}
max = {
cpu = "4"
memory = "8Gi"
}
}
]
}
}
}
},
# Tier 4-aux
{
name = "limitrange-tier-4-aux"
match = {
any = [
{
resources = {
kinds = ["Namespace"]
selector = {
matchLabels = {
tier = "4-aux"
}
}
}
}
]
}
generate = {
synchronize = true
apiVersion = "v1"
kind = "LimitRange"
name = "tier-defaults"
namespace = "{{request.object.metadata.name}}"
data = {
spec = {
limits = [
{
type = "Container"
default = {
cpu = "500m"
memory = "1Gi"
}
defaultRequest = {
cpu = "25m"
memory = "64Mi"
}
max = {
cpu = "2"
memory = "4Gi"
}
}
]
}
}
}
},
# Fallback: namespaces without a tier label get aux-level defaults
{
name = "limitrange-no-tier-fallback"
match = {
any = [
{
resources = {
kinds = ["Namespace"]
}
}
]
}
exclude = {
any = [
{
resources = {
selector = {
matchExpressions = [
{
key = "tier"
operator = "Exists"
}
]
}
}
},
{
resources = {
namespaces = ["kube-system", "metallb-system", "kyverno", "calico-system", "calico-apiserver"]
}
}
]
}
generate = {
synchronize = true
apiVersion = "v1"
kind = "LimitRange"
name = "tier-defaults"
namespace = "{{request.object.metadata.name}}"
data = {
spec = {
limits = [
{
type = "Container"
default = {
cpu = "500m"
memory = "1Gi"
}
defaultRequest = {
cpu = "25m"
memory = "64Mi"
}
max = {
cpu = "2"
memory = "4Gi"
}
}
]
}
}
}
},
]
}
}
}
# -----------------------------------------------------------------------------
# Layer 3: ResourceQuotas (Kyverno Generate)
# -----------------------------------------------------------------------------
# Creates a ResourceQuota in each namespace based on its tier label.
# Sets hard ceiling on total namespace resource consumption.
# Namespaces with label resource-governance/custom-quota=true are excluded.
#
# IMPORTANT: LimitRange (Layer 2) must exist before ResourceQuota takes effect,
# because ResourceQuota requires all pods to have resource requests set.
resource "kubernetes_manifest" "generate_resourcequota_by_tier" {
depends_on = [kubernetes_manifest.generate_limitrange_by_tier]
manifest = {
apiVersion = "kyverno.io/v1"
kind = "ClusterPolicy"
metadata = {
name = "generate-resourcequota-by-tier"
annotations = {
"policies.kyverno.io/title" = "Generate ResourceQuota by Tier"
"policies.kyverno.io/description" = "Creates tier-appropriate ResourceQuota in namespaces based on their tier label. Excludes namespaces with resource-governance/custom-quota label."
}
}
spec = {
generateExisting = true
rules = [
# Tier 0-core
{
name = "quota-tier-0-core"
match = {
any = [
{
resources = {
kinds = ["Namespace"]
selector = {
matchLabels = {
tier = "0-core"
}
}
}
}
]
}
exclude = {
any = [
{
resources = {
selector = {
matchLabels = {
"resource-governance/custom-quota" = "true"
}
}
}
}
]
}
generate = {
synchronize = true
apiVersion = "v1"
kind = "ResourceQuota"
name = "tier-quota"
namespace = "{{request.object.metadata.name}}"
data = {
spec = {
hard = {
"requests.cpu" = "8"
"requests.memory" = "8Gi"
"limits.cpu" = "32"
"limits.memory" = "64Gi"
pods = "100"
}
}
}
}
},
# Tier 1-cluster
{
name = "quota-tier-1-cluster"
match = {
any = [
{
resources = {
kinds = ["Namespace"]
selector = {
matchLabels = {
tier = "1-cluster"
}
}
}
}
]
}
exclude = {
any = [
{
resources = {
selector = {
matchLabels = {
"resource-governance/custom-quota" = "true"
}
}
}
}
]
}
generate = {
synchronize = true
apiVersion = "v1"
kind = "ResourceQuota"
name = "tier-quota"
namespace = "{{request.object.metadata.name}}"
data = {
spec = {
hard = {
"requests.cpu" = "4"
"requests.memory" = "4Gi"
"limits.cpu" = "16"
"limits.memory" = "32Gi"
pods = "30"
}
}
}
}
},
# Tier 2-gpu
{
name = "quota-tier-2-gpu"
match = {
any = [
{
resources = {
kinds = ["Namespace"]
selector = {
matchLabels = {
tier = "2-gpu"
}
}
}
}
]
}
exclude = {
any = [
{
resources = {
selector = {
matchLabels = {
"resource-governance/custom-quota" = "true"
}
}
}
}
]
}
generate = {
synchronize = true
apiVersion = "v1"
kind = "ResourceQuota"
name = "tier-quota"
namespace = "{{request.object.metadata.name}}"
data = {
spec = {
hard = {
"requests.cpu" = "4"
"requests.memory" = "4Gi"
"limits.cpu" = "32"
"limits.memory" = "64Gi"
pods = "30"
}
}
}
}
},
# Tier 3-edge
{
name = "quota-tier-3-edge"
match = {
any = [
{
resources = {
kinds = ["Namespace"]
selector = {
matchLabels = {
tier = "3-edge"
}
}
}
}
]
}
exclude = {
any = [
{
resources = {
selector = {
matchLabels = {
"resource-governance/custom-quota" = "true"
}
}
}
}
]
}
generate = {
synchronize = true
apiVersion = "v1"
kind = "ResourceQuota"
name = "tier-quota"
namespace = "{{request.object.metadata.name}}"
data = {
spec = {
hard = {
"requests.cpu" = "2"
"requests.memory" = "2Gi"
"limits.cpu" = "8"
"limits.memory" = "16Gi"
pods = "20"
}
}
}
}
},
# Tier 4-aux
{
name = "quota-tier-4-aux"
match = {
any = [
{
resources = {
kinds = ["Namespace"]
selector = {
matchLabels = {
tier = "4-aux"
}
}
}
}
]
}
exclude = {
any = [
{
resources = {
selector = {
matchLabels = {
"resource-governance/custom-quota" = "true"
}
}
}
}
]
}
generate = {
synchronize = true
apiVersion = "v1"
kind = "ResourceQuota"
name = "tier-quota"
namespace = "{{request.object.metadata.name}}"
data = {
spec = {
hard = {
"requests.cpu" = "1"
"requests.memory" = "1Gi"
"limits.cpu" = "4"
"limits.memory" = "8Gi"
pods = "15"
}
}
}
}
},
]
}
}
}
# -----------------------------------------------------------------------------
# Layer 4: PriorityClassName Injection (Kyverno Mutate)
# -----------------------------------------------------------------------------
# Automatically sets priorityClassName on Pods based on their namespace's tier label.
# Skips pods that already have a priorityClassName set.
resource "kubernetes_manifest" "mutate_priority_from_tier" {
manifest = {
apiVersion = "kyverno.io/v1"
kind = "ClusterPolicy"
metadata = {
name = "inject-priority-class-from-tier"
annotations = {
"policies.kyverno.io/title" = "Inject PriorityClass from Tier"
"policies.kyverno.io/description" = "Sets priorityClassName on Pods based on the namespace tier label. Skips pods that already have a priorityClassName."
}
}
spec = {
rules = [
{
name = "inject-priority-class"
match = {
any = [
{
resources = {
kinds = ["Pod"]
}
}
]
}
exclude = {
any = [
{
resources = {
namespaces = ["kube-system", "metallb-system", "kyverno", "calico-system", "calico-apiserver"]
}
}
]
}
context = [
{
name = "tierLabel"
apiCall = {
urlPath = "/api/v1/namespaces/{{request.namespace}}"
jmesPath = "metadata.labels.tier || ''"
}
}
]
preconditions = {
all = [
{
key = "{{request.object.spec.priorityClassName || ''}}"
operator = "Equals"
value = ""
},
{
key = "{{tierLabel}}"
operator = "NotEquals"
value = ""
}
]
}
mutate = {
patchStrategicMerge = {
spec = {
priorityClassName = "tier-{{tierLabel}}"
}
}
}
}
]
}
}
}

View file

@ -21,7 +21,8 @@ resource "kubernetes_namespace" "monitoring" {
name = "monitoring"
labels = {
"istio-injection" : "disabled"
tier = var.tier
tier = var.tier
"resource-governance/custom-quota" = "true"
}
}
}
@ -181,3 +182,20 @@ resource "kubernetes_ingress_v1" "status_yotovski" {
}
}
# Custom ResourceQuota for monitoring larger than the default 1-cluster tier quota
# because monitoring runs 29+ pods (Prometheus, Grafana, Loki, Alloy, exporters, etc.)
resource "kubernetes_resource_quota" "monitoring" {
metadata {
name = "monitoring-quota"
namespace = kubernetes_namespace.monitoring.metadata[0].name
}
spec {
hard = {
"requests.cpu" = "16"
"requests.memory" = "16Gi"
"limits.cpu" = "64"
"limits.memory" = "128Gi"
pods = "100"
}
}
}