fix(helm): scale the classic chart's HPA out at the documented 60 percent CPU (#35975)

* fix(helm): scale the classic chart's HPA out at the documented 60 percent CPU

The litellm-helm chart shipped targetCPUUtilizationPercentage: 80, which is
unexamined helm create scaffold rather than a chosen number. It arrived packaged
with the stock minReplicas: 1, maxReplicas: 100, a commented-out
targetMemoryUtilizationPercentage: 80, and the boilerplate "such as Minikube"
comment, the same provenance as the 128Mi resource example this file just
corrected.

60 is the documented recommendation. The mechanism behind it is scale-up lag:
the chart's own startupProbe is failureThreshold: 30 times periodSeconds: 10, so
a replica can take up to 300 seconds to become ready, and a pod added at 80
percent utilization arrives minutes after saturation.

The memory target stays commented out on purpose. The prisma query engine's
resident memory is a high-water mark that ratchets to the pod's worst-ever write
and is never returned, so a memory-target HPA reads the largest write a pod ever
did rather than what it is doing now, and replicas ratchet up without scaling
back in.

hpa_tests.yaml carried its second suite after a YAML document separator, and
helm-unittest loads only the first document per file, so that suite never ran;
an assertion planted in it still passed. Fold it into the one live suite and add
coverage pinning the rendered CPU target, the absence of a memory metric by
default, and that overrides still take effect.

Bump the chart to 1.1.2, since rendered output changes for anyone running with
autoscaling enabled.

* fix(helm): bump litellm-helm to 1.1.3 after rebase onto 1.1.2

Co-Authored-By: Devin AI <158243242+devin-ai-integration[bot]@users.noreply.github.com>

---------

Co-authored-by: Devin AI <158243242+devin-ai-integration[bot]@users.noreply.github.com>

helm/litellm-helm/Chart.yaml

@@ -18,7 +18,7 @@ type: application
 # This is the chart version. This version number should be incremented each time you make changes
 # to the chart and its templates, including the app version.
 # Versions are expected to follow Semantic Versioning (https://semver.org/)
-version: 1.1.2
+version: 1.1.3
 
 # This is the version number of the application being deployed. This version number should be
 # incremented each time you make changes to the application. Versions are not expected to

helm/litellm-helm/tests/hpa_tests.yaml

@@ -1,4 +1,4 @@
-suite: "hpa with behavior"
+suite: "hpa"
 templates:
   - hpa.yaml
 tests:
@@ -23,14 +23,44 @@ tests:
       - equal: { path: spec.behavior.scaleUp.stabilizationWindowSeconds, value: 60 }
       - equal: { path: spec.behavior.scaleDown.stabilizationWindowSeconds, value: 90 }
 
----
-suite: "hpa without behavior"
-templates:
-  - hpa.yaml
-tests:
   - it: "does not render behavior when not set"
     set:
       autoscaling.enabled: true
     asserts:
       - isKind: { of: HorizontalPodAutoscaler }
       - isNull: { path: spec.behavior }
+
+  - it: "scales on cpu at the documented 60 percent by default"
+    set:
+      autoscaling.enabled: true
+    asserts:
+      - isKind: { of: HorizontalPodAutoscaler }
+      - equal: { path: "spec.metrics[0].resource.name", value: cpu }
+      - equal: { path: "spec.metrics[0].resource.target.type", value: Utilization }
+      - equal: { path: "spec.metrics[0].resource.target.averageUtilization", value: 60 }
+
+  - it: "does not scale on memory by default"
+    set:
+      autoscaling.enabled: true
+    asserts:
+      - lengthEqual: { path: spec.metrics, count: 1 }
+
+  - it: "honours an explicit cpu target override"
+    set:
+      autoscaling.enabled: true
+      autoscaling.targetCPUUtilizationPercentage: 75
+    asserts:
+      - equal: { path: "spec.metrics[0].resource.target.averageUtilization", value: 75 }
+
+  - it: "renders a memory metric only when a memory target is set"
+    set:
+      autoscaling.enabled: true
+      autoscaling.targetMemoryUtilizationPercentage: 80
+    asserts:
+      - lengthEqual: { path: spec.metrics, count: 2 }
+      - equal: { path: "spec.metrics[1].resource.name", value: memory }
+      - equal: { path: "spec.metrics[1].resource.target.averageUtilization", value: 80 }
+
+  - it: "renders no hpa when autoscaling is disabled"
+    asserts:
+      - hasDocuments: { count: 0 }

helm/litellm-helm/values.yaml

@@ -200,7 +200,16 @@ autoscaling:
   enabled: false
   minReplicas: 1
   maxReplicas: 100
-  targetCPUUtilizationPercentage: 80
+  # 60 is the documented recommendation. See "Recommended Machine Specifications"
+  # in https://docs.litellm.ai/docs/proxy/prod. A new replica clears the startupProbe
+  # above only after up to failureThreshold x periodSeconds = 300 seconds, so a target
+  # high enough to trip near saturation adds capacity minutes after it was needed.
+  targetCPUUtilizationPercentage: 60
+  # Deliberately left unset rather than given a value. The prisma query engine's
+  # resident memory is a high-water mark that ratchets to the pod's worst-ever write
+  # and is never returned, so a memory target reads the largest write a pod ever did
+  # rather than what it is doing now, and replicas ratchet up without scaling back in.
+  # Memory is a floor to provision under 'resources', not a signal to scale on.
   # targetMemoryUtilizationPercentage: 80
   # behavior: {}