From 12b9a197a4715f109aacc59f094189a1f1e66f0f Mon Sep 17 00:00:00 2001
From: Gabi Davar <grizzly.nyo@gmail.com>
Date: Wed, 7 Aug 2024 11:23:42 +0300
Subject: [PATCH] Tell Go runtime about the CPU & memory limits. (#699)

* Tell Go runtime about the CPU & memory limits.

Signed-off-by: Gabi Davar <grizzly.nyo@gmail.com>

* review comments

---------

Signed-off-by: Gabi Davar <grizzly.nyo@gmail.com>
---
 .github/workflows/push.yaml                   |  4 ++--
 .../chart/reloader/templates/deployment.yaml  | 19 ++++++++++++++++---
 .../kubernetes/chart/reloader/values.yaml     |  5 +++++
 3 files changed, 23 insertions(+), 5 deletions(-)

diff --git a/.github/workflows/push.yaml b/.github/workflows/push.yaml
index 3e9524c3e..a7a665aa2 100644
--- a/.github/workflows/push.yaml
+++ b/.github/workflows/push.yaml
@@ -212,8 +212,8 @@ jobs:
       - name: Helm Template
         run: |
           helm template reloader deployments/kubernetes/chart/reloader/ \
-            --set reloader.deployment.resources.limits.cpu=150m \
-            --set reloader.deployment.resources.limits.memory=512Mi \
+            --set-string reloader.deployment.resources.limits.cpu=1 \
+            --set reloader.deployment.resources.limits.memory=128Mi \
             --set reloader.deployment.resources.requests.cpu=10m \
             --set reloader.deployment.resources.requests.memory=128Mi > deployments/kubernetes/reloader.yaml
           
diff --git a/deployments/kubernetes/chart/reloader/templates/deployment.yaml b/deployments/kubernetes/chart/reloader/templates/deployment.yaml
index e1105343b..d43bd872b 100644
--- a/deployments/kubernetes/chart/reloader/templates/deployment.yaml
+++ b/deployments/kubernetes/chart/reloader/templates/deployment.yaml
@@ -76,8 +76,23 @@ spec:
       - image: "{{ .Values.reloader.deployment.image.name }}:{{ .Values.reloader.deployment.image.tag }}"
         imagePullPolicy: {{ .Values.reloader.deployment.image.pullPolicy }}
         name: {{ template "reloader-fullname" . }}
-      {{- if or (.Values.reloader.deployment.env.open) (.Values.reloader.deployment.env.secret) (.Values.reloader.deployment.env.field) (.Values.reloader.deployment.env.existing) (eq .Values.reloader.watchGlobally false) (.Values.reloader.enableHA) (.Values.reloader.enableMetricsByNamespace)}}
         env:
+        - name: GOMAXPROCS
+        {{- if .Values.reloader.deployment.gomaxprocsOverride }}
+          value: {{ .Values.reloader.deployment.gomaxprocsOverride | quote }}
+        {{- else }}
+          valueFrom:
+            resourceFieldRef:
+              resource: limits.memory
+        {{- end }}
+        - name: GOMEMLIMIT
+        {{- if .Values.reloader.deployment.gomemlimitOverride }}
+          value: {{ .Values.reloader.deployment.gomemlimitOverride | quote }}
+        {{- else }}
+          valueFrom:
+            resourceFieldRef:
+              resource: limits.cpu
+        {{- end }}
       {{- range $name, $value := .Values.reloader.deployment.env.open }}
       {{- if not (empty $value) }}
         - name: {{ $name | quote }}
@@ -112,7 +127,6 @@ spec:
             fieldRef:
               fieldPath: {{ $value | quote}}
       {{- end }}
-      {{- end }}
       {{- if eq .Values.reloader.watchGlobally false }}
         - name: KUBERNETES_NAMESPACE
           valueFrom:
@@ -134,7 +148,6 @@ spec:
           value: enabled
       {{- end }}
       {{- end }}
-
         ports:
         - name: http
           containerPort: 9090
diff --git a/deployments/kubernetes/chart/reloader/values.yaml b/deployments/kubernetes/chart/reloader/values.yaml
index bb0f55e54..629dafb1b 100644
--- a/deployments/kubernetes/chart/reloader/values.yaml
+++ b/deployments/kubernetes/chart/reloader/values.yaml
@@ -147,6 +147,11 @@ reloader:
     # imagePullSecrets:
     #   - name: myregistrykey
 
+    # Put "0" in either to have go runtime ignore the set value.
+    # Otherwise, see https://pkg.go.dev/runtime#hdr-Environment_Variables for GOMAXPROCS and GOMEMLIMIT
+    gomaxprocsOverride: ""
+    gomemlimitOverride: ""
+
   service: {}
     # labels: {}
     # annotations: {}