From c3084225b7f50dce5fa7e7885513fdf7c0ded6b4 Mon Sep 17 00:00:00 2001
From: Mayne0213 <bluemayne0213@icloud.com>
Date: Sat, 10 Jan 2026 13:46:02 +0900
Subject: [PATCH] PERF(observability): add HA for Loki and Tempo
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

- Loki: replicas 1→2 with soft anti-affinity
- Tempo: replicas 1→2 with soft anti-affinity
- Thanos/Prometheus: keep replica 1

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
---
 loki/helm-values.yaml       | 12 +++++++++++-
 prometheus/helm-values.yaml |  2 +-
 tempo/helm-values.yaml      | 14 ++++++++++++++
 3 files changed, 26 insertions(+), 2 deletions(-)

diff --git a/loki/helm-values.yaml b/loki/helm-values.yaml
index 48edf2c..6e43a98 100644
--- a/loki/helm-values.yaml
+++ b/loki/helm-values.yaml
@@ -45,10 +45,20 @@ loki:
 deploymentMode: SingleBinary
 
 singleBinary:
-  replicas: 1
+  replicas: 2
   # Disable PVC - use emptyDir for WAL (data stored in MinIO)
   persistence:
     enabled: false
+  # Soft anti-affinity for HA
+  affinity:
+    podAntiAffinity:
+      preferredDuringSchedulingIgnoredDuringExecution:
+        - weight: 100
+          podAffinityTerm:
+            labelSelector:
+              matchLabels:
+                app.kubernetes.io/name: loki
+            topologyKey: kubernetes.io/hostname
   extraVolumes:
     - name: data
       emptyDir:
diff --git a/prometheus/helm-values.yaml b/prometheus/helm-values.yaml
index 396722d..e75b12e 100644
--- a/prometheus/helm-values.yaml
+++ b/prometheus/helm-values.yaml
@@ -70,7 +70,7 @@ prometheus:
     # Enable remote write receiver for OTel Collector
     enableRemoteWriteReceiver: true
 
-    # Single replica (HA removed for resource optimization)
+    # Single replica
     replicas: 1
     replicaExternalLabelName: prometheus_replica
 
diff --git a/tempo/helm-values.yaml b/tempo/helm-values.yaml
index 8f5684c..b05b76d 100644
--- a/tempo/helm-values.yaml
+++ b/tempo/helm-values.yaml
@@ -10,6 +10,20 @@
 # Medium priority for observability
 priorityClassName: medium-priority
 
+# HA with 2 replicas
+replicas: 2
+
+# Soft anti-affinity for HA
+affinity:
+  podAntiAffinity:
+    preferredDuringSchedulingIgnoredDuringExecution:
+      - weight: 100
+        podAffinityTerm:
+          labelSelector:
+            matchLabels:
+              app.kubernetes.io/name: tempo
+          topologyKey: kubernetes.io/hostname
+
 # =============================================================================
 # Resource Limits (optimized for small cluster)
 # =============================================================================