This topic provides an overview of the monitoring for the Druid service.

Prerequisites

A Druid cluster is created. For more information, see Create a cluster.

Go to the DRUID Monitoring page

  1. Log on to the Alibaba Cloud EMR console.
  2. In the top navigation bar, select the region where your cluster resides and select a resource group based on your business requirements.
  3. Click the Monitor tab.
  4. In the left-side navigation pane, click Cluster Monitoring.
  5. On the Cluster Status page, find the cluster whose monitoring data you want to view, and click Details in the Action column.
  6. In the left-side navigation pane, choose Service Monitoring > Druid.

    The DRUID Monitoring page appears.

DRUID Monitoring page

The DRUID Monitoring page displays basic metric charts, recent alerts and exceptions, and information of processes such as Broker, Coordinator, Historical, Overlord, and Middle Manager. It also displays the statistics of Druid Queries Core Performance Indicators and Druid Ingestion Core Performance Indicators.

  • Basic metric charts: The charts include Alerts (Today), Tasks (Today), Segments, and Historical Cache Usage.
  • Alerts and Details: This section displays alerts and exceptions related to the Druid service on the current day.
  • Broker. Broker
    Parameter Description
    Instance Name The name of the Broker process. You can click the name to view monitoring details.
    Port Status The port status of the Broker process. Green indicates that the port is normal. Red indicates that the port is abnormal.
    Process CPU Usage The CPU utilization of the Broker process.
    Heap Memory The heap memory usage of the Broker process. The heap memory usage items include Heap Used, Heap Committed, Heap Max, and Heap Init.
    Non-Heap Memory The non-heap memory usage of the Broker process. The non-heap memory usage items include NonHeap Committed, NonHeap Used, and NonHeap Init.
    JVM Garbage Collection Statistics The garbage collection statistics of the Broker Java process displayed in the jstat -gcutil format.
    • S0: the capacity usage of survivor space 1 (%)
    • S1: the capacity usage of survivor space 2 (%)
    • O: the capacity usage of the old generation space (%)
    • E: the capacity usage of the Eden space (%)
    • M: the capacity usage of the metaspace (%)
    • CCS: the capacity usage of the Compressed Class Space (%)
    • YGCT: the time consumed by garbage collection in the young generation space
    • FGCT: the time consumed by garbage collection in the old generation space
    • GCT: the total time consumed by garbage collection
    • YGC: the number of times garbage is collected in the young generation space
    • FGC: the number of times garbage is collected in the old generation space
  • Coordinator. Coordinator

    For information about the parameters, see Broker section.

  • Historical. Historical

    For information about the parameters, see Broker section.

  • Overlord. Overlord

    For information about the parameters, see Broker section.

  • Middle Manager. Middle Manager

    For information about the parameters, see Broker section.

  • Druid Queries Core Performance Indicators.

    This section displays the Average Queries per Minute and Average Query Processing Time charts. Select Search Type is set to All Queries by default. You can select a different search type. You can select a time range and an interval for these charts.

  • Druid Ingestion Core Performance Indicators.

    This section displays the Average Events Processed per Minute and Average Rows Output per Minute charts. These charts represent the data ingestion performance of a Druid cluster. You can select a time range and an interval for these charts.

Monitoring details page for each process

On the DRUID Monitoring page, you can click a name in each of the sections to go to the monitoring details page for the required process. The sections include Broker, Coordinator, Historical, Overlord, and Middle Manager.

The monitoring details page displays the statistics of JVM metrics and file descriptors, and the start or stop history of the process. The monitoring details page is similar to that of other service components.