From 39df4f2469879dd0defe4ca7375c10bfbab5f0cf Mon Sep 17 00:00:00 2001
From: Dmitry Dementev <me@dementev.space>
Date: Sun, 8 Feb 2026 23:00:32 +0300
Subject: [PATCH] fix(monitoring): add missing ClickHouse Prometheus port and
 fix dashboard queries
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- Add port 9126 mapping for ClickHouse Prometheus metrics endpoint
  (was configured in prometheus_ch.xml but not exposed in docker-compose.yml)

- Fix CPU Usage panel: use delta() instead of rate() for gauge metric
  ClickHouseProfileEvents_OSCPUVirtualTimeMicroseconds is a gauge, not counter

- Add explicit datasource blocks to dashboard queries for consistency

ClickHouse ProfileEvents metrics correctly use rate() — they are counters.
Warning about missing _total suffix is expected (ClickHouse naming convention).
---
 .../provisioning/dashboards/clickhouse-overview.json | 12 ++++++++++++
 docker-compose.yml                                   |  1 +
 2 files changed, 13 insertions(+)

diff --git a/configs/grafana/provisioning/dashboards/clickhouse-overview.json b/configs/grafana/provisioning/dashboards/clickhouse-overview.json
index bc863dc..1a01e64 100644
--- a/configs/grafana/provisioning/dashboards/clickhouse-overview.json
+++ b/configs/grafana/provisioning/dashboards/clickhouse-overview.json
@@ -385,6 +385,10 @@
       },
       "targets": [
         {
+          "datasource": {
+            "type": "prometheus",
+            "uid": "prometheus_uid"
+          },
           "expr": "rate(ClickHouseProfileEvents_Query[1m])",
           "refId": "A"
         }
@@ -671,6 +675,10 @@
       },
       "targets": [
         {
+          "datasource": {
+            "type": "prometheus",
+            "uid": "prometheus_uid"
+          },
           "expr": "rate(ClickHouseProfileEvents_InsertedRows[1m])",
           "refId": "A"
         }
@@ -967,6 +975,10 @@
       },
       "targets": [
         {
+          "datasource": {
+            "type": "prometheus",
+            "uid": "prometheus_uid"
+          },
           "expr": "rate(ClickHouseProfileEvents_Merge[1m])",
           "refId": "A"
         }
diff --git a/docker-compose.yml b/docker-compose.yml
index 12d07be..f4dd504 100644
--- a/docker-compose.yml
+++ b/docker-compose.yml
@@ -35,6 +35,7 @@ services:
     ports:
       - "8002:9000"
       - "9123:8123"
+      - "9126:9126"  # ClickHouse Prometheus metrics endpoint
 
   kafka:
     image: apache/kafka:3.8.0