ClickHouse is an open-source, column-oriented OLAP (Online Analytical Processing) database optimized for high-performance analytical queries on massive datasets. It supports distributed query execution, compression, and vectorized processing to deliver sub-second query responses even on billions of rows.
Applications Manager provides comprehensive support for ClickHouse monitoring by leveraging Prometheus-based data collection to gain complete visibility into database performance, resource utilization, and cluster health. This helps administrators identify bottlenecks, optimize queries, and maintain consistent performance across deployments.
Applications Manager: The robust ClickHouse monitoring solution you need
Applications Manager enables you to track the performance of your ClickHouse databases by obtaining detailed insights into the following components:
- ClickHouse performance monitoring
- Query performance analysis
- Resource usage statistics
- Merge operations tracking
- Replication status summary
- IO and thread details
Monitor ClickHouse performance with real-time insights
Gain detailed insights into availability, health, and performance of your ClickHouse databases by continuously tracking query activity, data ingestion, and system behavior in real-time. Keep a close watch on the critical KPIs of your ClickHouse databases such as response time, server uptime and number of DB instances to ensure they are up and running without any interruptions. In addition, get complete visibility into different types of connections that are established with the database along with their count in a single view. With access to both real-time and historical data, users can easily identify performance degradation trends and take corrective actions before they impact business operations.
Analyze query volumes and database workloads
Gain a quick overview into the query performance patterns to help you optimize ClickHouse database optimally. Track query volumes, monitor active queries, and identify long-running or failed executions in your ClickHouse databases to help you evaluate workload distribution and improve query efficiency, ultimately reducing latency and enhancing database responsiveness. Examine out how many insert operations are performed into your ClickHouse databases along with the corresponding bytes and number of delays in performing insert operations to quickly find out the issues in your database inserts, if any.
Keep a close watch on resource usage stats
Since ClickHouse is well known for its high performance querying capabilities for faster analysis, ensuring efficient resource management is critical for ensuring seamless database operations. Obtain in-depth visibility into memory and disk usage statistics along with their split-ups to understand how system resources are being utilized. Keeping constant track over these metrics can prevent unprecedented resource exhaustion, plan capacity effectively, and ensure optimal infrastructure usage especially during critical business operations such as ecommerce, banking, or trading.
Obtain deep insights into background operations
Gain real-time visibility into ClickHouse's internal operations by monitoring data size, row count, partition structure, and merge activities to quickly detect inefficiencies and ensure optimal storage performance. Track the background operations of your database instances that comprises of merge and schedule pool tasks and their corresponding sizes to uncover internal bottlenecks and maintain peak performance. Monitoring these activities provides deeper insights into system behavior and helps identify internal bottlenecks that may affect performance and helps you guarantee system stability, efficiency, and responsiveness at all times.
Keep checks on replication status
Applications Manager enables you to monitor ClickHouse replication and ZooKeeper activity to maintain cluster consistency and availability. Track key replication metrics such as read-only replicas, replication queue size, part fetches, merges, and potential data loss to quickly identify lag, synchronization issues, or failures across nodes. In parallel, monitor ZooKeeper metrics—including active sessions, requests, and transactions to assess coordination health and detect bottlenecks affecting distributed operations. By continuously observing these metrics, you can promptly troubleshoot replication delays, prevent data inconsistencies, and ensure stable and reliable cluster performance.
Learn more about Zookeeper monitoring →
Keep track of threads and IO operations
Obtain in-depth insights into the thread activity and I/O operation of your ClickHouse databases to ensure optimal database performance and resource utilization. Monitor network and disk I/O metrics, including read and write throughput, to understand data access patterns and detect performance issues such as high latency or slow query execution. Keep check on thread utilization along with key thread metrics such as total, active, and idle threads to analyze concurrency levels and identify bottlenecks caused by thread exhaustion or contention. Additionally, gain complete visibility into open files and distributed tables of your ClickHouse databases to prevent system-level failures, and ensures your cluster delivers fast, accurate, and reliable results across all nodes.
In addition to monitoring ClickHouse databases, Applications Manager lets you track the health and performance of over 150+ infrastructure components—including databases, hosts, containers, middleware, and cloud services—along with full application performance and digital experience monitoring.
Common questions asked on ClickHouse monitoring
What is ClickHouse monitoring and why is it important?
ClickHouse monitoring involves tracking database performance, resource usage, and query activity to ensure optimal operation. It is important because it helps identify bottlenecks, prevent downtime, and maintain high query performance in real time.
How does Applications Manager monitor ClickHouse performance?
Applications Manager monitors ClickHouse using Prometheus-based integration to collect metrics such as queries, CPU, memory, disk I/O, replication status, and ZooKeeper activity. These metrics are visualized through dashboards and alerts for proactive performance management.
What metrics can I monitor with Applications Manager's ClickHouse monitoring?
With Applications Manager, you can monitor query execution metrics, memory usage, disk I/O, active connections, thread utilization, replication lag, and ZooKeeper health to ensure overall database performance and stability.
How can you detect slow queries in ClickHouse?
Slow queries can be identified by monitoring query execution time, active queries, and system resource usage. Sudden spikes in response time or high memory and disk usage often indicate inefficient or long-running queries.
What ZooKeeper metrics are critical for ClickHouse monitoring?
Key ZooKeeper metrics include active sessions, request rates, and transactions. Monitoring these helps ensure proper coordination between ClickHouse nodes and prevents cluster instability or failures.
What is the role of Prometheus in ClickHouse monitoring?
Prometheus acts as the data collection layer, exposing ClickHouse metrics which are then integrated into Applications Manager for visualization, alerting, and analysis.
How can you monitor distributed queries in ClickHouse?
Distributed query monitoring involves tracking network I/O, distributed sends, and pending inserts. These metrics help ensure efficient data transfer across shards and nodes.
What causes performance bottlenecks in ClickHouse and how can you monitor them?
Bottlenecks are often caused by inefficient queries, high concurrency, disk I/O limitations, or replication lag. Monitoring query metrics, thread usage, and disk throughput helps quickly identify and resolve these issues.
Can Applications Manager provide real-time alerts for ClickHouse issues?
Yes, Applications Manager provides real-time alerts based on thresholds and forecast trends. This helps detect anomalies early and take corrective actions before performance degradation occurs.
