feature: add pgbouncer for label-studio to resolve the 'too many conn…

deployment/docker/datamate/docker-compose.yml

@@ -199,6 +199,26 @@ services:
   # ==============================
   # Optional: Label Studio (profile: label-studio)
   # ==============================
+  label-studio-pgbouncer:
+    container_name: label-studio-pgbouncer
+    image: pgbouncer/pgbouncer:latest
+    restart: on-failure
+    ports:
+      - "6432:6432"
+    environment:
+      - DATABASES_HOST=datamate-database
+      - DATABASES_PORT=5432
+      - DATABASES_NAME=labelstudio
+      - DATABASES_USER=postgres
+      - DATABASES_PASSWORD=${DB_PASSWORD:-password}
+      - POOL_MODE=transaction
+      - MAX_CLIENT_CONN=100
+      - DEFAULT_POOL_SIZE=20
+      - MAX_DB_CONNECTIONS=20
+    networks:
+      - datamate
+    profiles: [ label-studio ]
+
   label-studio:
     container_name: label-studio
     stdin_open: true
@@ -212,14 +232,14 @@ services:
     ports:
       - "30001:8000"
     depends_on:
-      - datamate-database
+      - label-studio-pgbouncer
     environment:
       - DJANGO_DB=default
       - POSTGRE_NAME=labelstudio
       - POSTGRE_USER=postgres
       - POSTGRE_PASSWORD=${DB_PASSWORD:-password}
-      - POSTGRE_PORT=5432
-      - POSTGRE_HOST=datamate-database
+      - POSTGRE_PORT=6432
+      - POSTGRE_HOST=label-studio-pgbouncer
       - LABEL_STUDIO_HOST=${LABEL_STUDIO_HOST:-}
       - LOCAL_FILES_SERVING_ENABLED=true
       - LOCAL_FILES_DOCUMENT_ROOT=/label-studio/local

deployment/helm/label-studio/templates/deployment.yaml

@@ -38,9 +38,9 @@ spec:
             - name: POSTGRE_PASSWORD
               value: {{ .Values.env.POSTGRE_PASSWORD | quote }}
             - name: POSTGRE_PORT
-              value: {{ .Values.env.POSTGRE_PORT | quote }}
+              value: {{ if .Values.pgbouncer.enabled }}{{ "6432" | quote }}{{ else }}{{ .Values.env.POSTGRE_PORT | quote }}{{ end }}
             - name: POSTGRE_HOST
-              value: {{ .Values.env.POSTGRE_HOST | quote }}
+              value: {{ if .Values.pgbouncer.enabled }}{{ printf "%s-pgbouncer" (include "label-studio.fullname" .) | quote }}{{ else }}{{ .Values.env.POSTGRE_HOST | quote }}{{ end }}
             - name: LABEL_STUDIO_HOST
               value: {{ .Values.env.LABEL_STUDIO_HOST | quote }}
             - name: LOCAL_FILES_SERVING_ENABLED

deployment/helm/label-studio/templates/pgbouncer-deployment.yaml

@@ -0,0 +1,78 @@
+{{- if .Values.pgbouncer.enabled }}
+apiVersion: apps/v1
+kind: Deployment
+metadata:
+  name: {{ include "label-studio.fullname" . }}-pgbouncer
+  labels:
+    app.kubernetes.io/name: {{ include "label-studio.name" .}}-pgbouncer
+    helm.sh/chart: {{ include "label-studio.chart" . }}
+    app.kubernetes.io/instance: {{ .Release.Name }}
+    app.kubernetes.io/managed-by: {{ .Release.Service }}
+spec:
+  replicas: {{ .Values.pgbouncer.replicaCount }}
+  selector:
+    matchLabels:
+      app.kubernetes.io/name: {{ include "label-studio.name" . }}-pgbouncer
+      app.kubernetes.io/instance: {{ .Release.Name }}
+  template:
+    metadata:
+      labels:
+        app.kubernetes.io/name: {{ include "label-studio.name" . }}-pgbouncer
+        app.kubernetes.io/instance: {{ .Release.Name }}
+    spec:
+      containers:
+        - name: pgbouncer
+          {{- if .Values.global.imageRegistry }}
+          image: "{{ .Values.global.imageRegistry | trimSuffix "/" }}/{{ .Values.pgbouncer.image.repository }}:{{ .Values.pgbouncer.image.tag }}"
+          {{- else }}
+          image: "{{ .Values.pgbouncer.image.repository }}:{{ .Values.pgbouncer.image.tag }}"
+          {{- end }}
+          imagePullPolicy: {{ .Values.pgbouncer.image.pullPolicy }}
+          ports:
+            - name: pgbouncer
+              containerPort: 6432
+              protocol: TCP
+          env:
+            - name: DATABASES_HOST
+              value: {{ .Values.env.POSTGRE_HOST | quote }}
+            - name: DATABASES_PORT
+              value: {{ .Values.env.POSTGRE_PORT | quote }}
+            - name: DATABASES_NAME
+              value: {{ .Values.env.POSTGRE_NAME | quote }}
+            - name: DATABASES_USER
+              value: {{ .Values.env.POSTGRE_USER | quote }}
+            - name: DATABASES_PASSWORD
+              value: {{ .Values.env.POSTGRE_PASSWORD | quote }}
+            - name: POOL_MODE
+              value: {{ .Values.pgbouncer.poolMode | quote }}
+            - name: MAX_CLIENT_CONN
+              value: {{ .Values.pgbouncer.maxClientConn | quote }}
+            - name: DEFAULT_POOL_SIZE
+              value: {{ .Values.pgbouncer.defaultPoolSize | quote }}
+            - name: MAX_DB_CONNECTIONS
+              value: {{ .Values.pgbouncer.maxDbConnections | quote }}
+          livenessProbe:
+            tcpSocket:
+              port: 6432
+            initialDelaySeconds: 15
+            periodSeconds: 20
+          readinessProbe:
+            tcpSocket:
+              port: 6432
+            initialDelaySeconds: 5
+            periodSeconds: 10
+          resources:
+            {{- toYaml .Values.pgbouncer.resources | nindent 12 }}
+      {{- with .Values.pgbouncer.nodeSelector }}
+      nodeSelector:
+        {{- toYaml . | nindent 8 }}
+      {{- end }}
+      {{- with .Values.pgbouncer.affinity }}
+      affinity:
+        {{- toYaml . | nindent 8 }}
+      {{- end }}
+      {{- with .Values.pgbouncer.tolerations }}
+      tolerations:
+        {{- toYaml . | nindent 8 }}
+      {{- end }}
+{{- end }}

deployment/helm/label-studio/templates/pgbouncer-service.yaml

@@ -0,0 +1,21 @@
+{{- if .Values.pgbouncer.enabled }}
+apiVersion: v1
+kind: Service
+metadata:
+  name: {{ include "label-studio.fullname" . }}-pgbouncer
+  labels:
+    app.kubernetes.io/name: {{ include "label-studio.name" . }}-pgbouncer
+    helm.sh/chart: {{ include "label-studio.chart" . }}
+    app.kubernetes.io/instance: {{ .Release.Name }}
+    app.kubernetes.io/managed-by: {{ .Release.Service }}
+spec:
+  type: ClusterIP
+  ports:
+    - port: 6432
+      targetPort: pgbouncer
+      protocol: TCP
+      name: pgbouncer
+  selector:
+    app.kubernetes.io/name: {{ include "label-studio.name" . }}-pgbouncer
+    app.kubernetes.io/instance: {{ .Release.Name }}
+{{- end }}

deployment/helm/label-studio/values.yaml

@@ -66,4 +66,27 @@ datasetVolume:
   enabled: true
   claimName: datamate-dataset-pvc # if empty, uses same PVC as persistence or creates a dedicated one
 
+# PgBouncer configuration for connection pooling
+pgbouncer:
+  enabled: true
+  replicaCount: 1
+
+  image:
+    repository: pgbouncer/pgbouncer
+    tag: "latest"
+    pullPolicy: IfNotPresent
+
+  # Connection pool settings
+  poolMode: transaction  # transaction, session, or statement
+  maxClientConn: 100     # Maximum number of client connections
+  defaultPoolSize: 20    # Default pool size per database (max connections to PostgreSQL)
+  maxDbConnections: 20   # Maximum database connections (hard limit)
+
+  resources: {}
+
+  nodeSelector: {}
+
+  tolerations: []
+
+  affinity: {}