ClickHouse

Auto-Detection

Built-in Metrics

Prometheus Metrics

ClickHouse is a high-performance, column-oriented SQL database for real-time analytics.

Glouton can monitor ClickHouse in two ways:

Auto-detection — recommended, minimal configuration. Glouton detects ClickHouse and collects a curated set of built-in metrics.
Prometheus metrics — scrape ClickHouse’s native Prometheus endpoint for a fully customizable set of metrics.

Auto-Detection

Glouton detects ClickHouse by its process and listening port (default HTTP interface: 8123).

To gather metrics, Glouton queries ClickHouse’s system tables over the HTTP interface, which requires credentials. The user (default: default) must be allowed to read the system.* tables.

If the auto-detected parameters are incorrect, override them manually:

Linux
Windows

sudo tee /etc/glouton/conf.d/99-clickhouse.conf > /dev/null << 'EOF'
service:
  - type: "clickhouse"
    username: "default"
    password: "PASSWORD"
    address: "127.0.0.1"
    port: 8123
EOF

Create or edit C:\ProgramData\glouton\conf.d\99-clickhouse.conf:

service:
  - type: "clickhouse"
    username: "default"
    password: "PASSWORD"
    address: "127.0.0.1"
    port: 8123

Glouton automatically detects configuration changes.

Metric	Description
`service_status`	Status of ClickHouse
`clickhouse_events_query`	Number of queries executed per second
`clickhouse_events_select_query`	Number of SELECT queries executed per second
`clickhouse_events_failed_query`	Number of failed queries per second
`clickhouse_events_query_time_seconds`	Time spent executing queries per second, in seconds
`clickhouse_events_mutation_time_seconds`	Time spent applying mutations per second, in seconds
`clickhouse_events_slow_read`	Number of slow reads from the filesystem per second
`clickhouse_events_network_receive_bytes`	Bytes received over the network per second
`clickhouse_events_network_send_bytes`	Bytes sent over the network per second
`clickhouse_metrics_active_query`	Number of queries currently being executed
`clickhouse_metrics_memory_tracking`	Amount of memory currently allocated by the server, in bytes
`clickhouse_metrics_delayed_inserts`	Number of INSERT queries currently throttled because of too many parts
`clickhouse_metrics_broken_disks`	Number of disks currently in a broken state
`clickhouse_metrics_broken_distributed_bytes_to_insert`	Bytes of broken distributed data pending insertion
`clickhouse_metrics_broken_distributed_files_to_insert`	Number of broken distributed files pending insertion
`clickhouse_mutations_running`	Number of mutations currently running
`clickhouse_mutations_failed`	Number of failed mutations
`clickhouse_processes_longest_running`	Duration of the longest currently running query, in seconds
`clickhouse_asynchronous_metrics_replicas_max_queue_size`	Largest replication queue size across replicated tables

Prometheus Metrics

Service Configuration

ClickHouse exposes Prometheus metrics since version 20.1.2.4. Add a <prometheus> section to your configuration by editing config.xml or creating a drop-in file at /etc/clickhouse-server/config.d/prometheus.xml:

<clickhouse>
    <prometheus>
        <endpoint>/metrics</endpoint>
        <port>9363</port>
        <metrics>true</metrics>
        <events>true</events>
        <asynchronous_metrics>true</asynchronous_metrics>
    </prometheus>
</clickhouse>

Restart ClickHouse for the change to take effect. Metrics are then available at http://localhost:9363/metrics.

sudo tee /etc/glouton/conf.d/99-clickhouse.conf > /dev/null << 'EOF'
metric:
  prometheus:
    targets:
      - url: "http://localhost:9363/metrics"
        name: "clickhouse"
        allow_metrics:
          - "ClickHouseProfileEvents_Query"
          - "ClickHouseMetrics_Query"
          - "ClickHouseAsyncMetrics_*"
          - "ClickHouseProfileEvents_InsertedRows"
          - "ClickHouseMetrics_MemoryTracking"
EOF

Create or edit C:\ProgramData\glouton\conf.d\99-clickhouse.conf:

metric:
  prometheus:
    targets:
      - url: "http://localhost:9363/metrics"
        name: "clickhouse"
        allow_metrics:
          - "ClickHouseProfileEvents_Query"
          - "ClickHouseMetrics_Query"
          - "ClickHouseAsyncMetrics_*"
          - "ClickHouseProfileEvents_InsertedRows"
          - "ClickHouseMetrics_MemoryTracking"

Glouton automatically detects configuration changes.

Metric	Description
`ClickHouseProfileEvents_Query`	Total number of queries executed by ClickHouse
`ClickHouseMetrics_Query`	Number of queries currently being executed
`ClickHouseAsyncMetrics_*`	Asynchronous metrics including system-level resource usage
`ClickHouseProfileEvents_InsertedRows`	Total number of rows inserted into tables
`ClickHouseMetrics_MemoryTracking`	Amount of memory currently allocated by the server in bytes