• Data Warehouse Service

dws
  1. Help Center
  2. Data Warehouse Service
  3. User Guide
  4. Monitoring a Cluster

Monitoring a Cluster

Scenario

This section describes how to check cluster metrics on Cloud Eye. By monitoring cluster running metrics, you can identify the time when the database cluster is abnormal and analyze potential activity problems based on the database logs, improving database performance. This section is organized as follows:

Monitoring Metrics of a Cluster

With the DWS monitoring metrics provided by Cloud Eye, you can obtain information about the cluster running status and performance. This information will provide a better understanding of the node-level information.

Table 1 describes DWS monitoring metrics.

Table 1 DWS monitoring metrics

Name

Description

Value Range

Object

Shared Memory Hit Ratio

Percentage of data volume obtained from memory, expressed in percentage

0% to 100%

Data warehouse clusters

In-memory Sort Ratio

Percentage of data volume that is sorted in memory, expressed in percentage

0% to 100%

File Reads

Total number of database file reads

> 0

File Writes

Total number of database file writes

> 0

File Reads per Second

Number of database file reads per second

≥ 0

File Writes per Second

Number of database file writes per second

≥ 0

Data Volume

Total data volume of the database, expressed in MB

0 to 36000 MB

Active SQL Count

Number of active SQLs in the database

≥ 0

Session Count

Number of sessions that access the database

≥ 0

CPU Usage

CPU usages of each node in the cluster, expressed in percentage

0% to 100%

Nodes in the cluster

Memory Usage

Memory usages of each node in the cluster, expressed in percentage

0% to 100%

IOPS

Number of I/O requests processed by each node in the cluster per second

≥ 0

Network Input Throughput

Data input to each node in the cluster per second over the network

≥ 0 bytes/s

Network Output Throughput

Data sent to the network per second from each node in the cluster

≥ 0 bytes/s

Disk Usage

Disk usages of each node in the cluster, expressed in percentage

0% to 100%

Total Disk Size

Total disk space of each node in the cluster, expressed in GB

100 to 2000 GB

Used Disk Space

Used disk space of each node in the cluster, expressed in GB

0 to 3600 GB

Disk Read Throughput

Data volume read by each disk in the cluster per second, expressed in byte/s

≥ 0 bytes/s

Disk Write Throughput

Data volume written to each disk per second, expressed in byte/s

≥ 0 bytes/s

Average Time per Disk Read

Average time used each time when a disk reads data, expressed in seconds

> 0s

Average Time per Disk Write

Average time used each time when data is written to a disk, expressed in seconds

> 0s

Average Disk Queue Length

Average I/O queue length of a disk

≥ 0

Viewing Monitoring Information of a Cluster

  1. Log in to the DWS management console.
  2. Click Cluster Management.
  3. In the cluster list, click View Metric in the Operation column where a specific cluster resides. The Cloud Eye management console is displayed.

    On Cloud Eye, you can view monitoring metrics of data warehouse clusters and monitoring information about each node in the cluster. Additionally, you can specify a specific monitoring metric and the time range to view the performance curve.

    Cloud Eye also supports the ability to compare the monitoring metrics of multiple nodes. For details, see Comparing the Monitoring Metrics of Multiple Nodes.

Comparing the Monitoring Metrics of Multiple Nodes

  1. In the navigation tree on the left of the Cloud Eye management console, choose Dashboard > Monitoring Panels.
  2. On the Monitoring Panels page, click Create Panel. In the displayed dialog box, enter the Name and click OK.
  3. On the Monitoring Panels page, click Add Graph in the upper right corner.
  4. In the Add Graph window, configure the title and monitoring metrics.

    NOTE:

    You can add multiple monitoring metrics by clicking Add Metric.

    The following describes how to set parameters if you want to compare CPU usage of two nodes.

    Figure 1 Add Graph
    Table 2 Configuration example

    Parameter

    Example Value

    Resource Type

    DWS

    Dimension

    Data Warehouse Node

    Monitored Object

    dws-64a3-dws-dn-1-1

    dws-64a3-dws-cn-cn-1-1

    Metric

    CPU Usage

  5. Click OK.

    After the monitoring metrics are added successfully, you can view the corresponding monitoring graph on the Monitoring Panels page. Move the cursor to the graph and click in the upper right corner to zoom in the graph and view detailed metric comparison data.

Creating Alarm Rules

Setting DWS alarm rules allows you to customize the monitored objects and notification policies and determine the running status of your DWS at any time.

A DWS alarm rule includes the alarm rule name, monitored object, metric, threshold, monitoring interval, and whether to send a notification. This section describes how to set DWS alarm rules.

  1. Log in to the management console at https://console.otc.t-systems.com/dws/.
  2. In the navigation tree on the left, click Cluster Management.
  3. Locate the row containing the target cluster, click View Metric in the Operation column to enter the Cloud Eye management console and view the DWS monitoring information.

    The status of the target cluster must be Available. Otherwise, you cannot create alarm rules.

  4. In the left navigation pane of the Cloud Eye management console, choose Alarm Management > Alarm Rules.
  5. On the Alarm Rules page, click Create Alarm Rule in the upper right corner.
  6. On the Create Alarm Rule page, set parameters as prompted.

    1. Select the object to be monitored, set the parameters, and click Next.
      Figure 2 Selecting the object to be monitored
      Table 3 Selecting the object to be monitored

      Parameter

      Description

      Example Value

      Resource Type

      Name of the cloud service resource for which the alarm rule is configured

      Data Warehouse Service

      Dimension

      Metric dimension of the alarm rule. You can select Data Warehouse Nodes or Data Warehouses.

      Data Warehouses

      Monitored Object

      Specific resources monitored by the alarm rule. You can specify one or more resources for monitoring. Select the ID of the cluster instance or node you have created.

      -

    2. Select the monitoring metric. You can select either of the following methods and set parameters as prompted.
      • Create Manually

        If no alarm template is available, set Method to Create manually and configure related parameters to create an alarm rule.

        Figure 3 Selecting the metric

          

        Table 4 Related parameters

        Parameter

        Description

        Example Value

        Method

        Select Create manually.

        Create manually

        Metric

        Select a metric supported by DWS. For details, see section Table 1.

        For example:

        • CPU Usage

          CPU usage of the monitored object, expressed in percentage

        • Data Volume

          Total data volume of the database, expressed in MB

        Data Volumn

        Alarm Policy

        Policy that triggers an alarm

        For example, trigger an alarm if the metric raw data equals to or is greater than 80% for 3 consecutive periods of 5 minutes.

        -

        Alarm Severity

        Severity of an alarm. Valid values are Critical, Major, Minor, and Informational.

        Major

        Alarm Notification

        Whether to notify users when alarms are triggered. Notifications can be sent as emails or text messages, or HTTP/HTTPS requests sent to the servers.

        You can enable (recommended) or disable Alarm Notification.

        Enable

        Topic

        Name of the topic to which the alarm notification is sent

        If you enable Alarm Notification, you need to select a topic. If no desired topics are available, create one first, whereupon the SMN service is invoked. For details about how to create a topic, see the Simple Message Notification User Guide.

        -

        Trigger Condition

        Condition for triggering the alarm. You can select Generated alarm, Cleared alarm, or both.

        -

      • Use template

        If you have available alarm rule templates, Set Method to Use Template, so that you can use a template to quickly create alarm rules.

        Figure 4 Using an alarm rule template
        Table 5 Related parameters

        Parameter

        Description

        Example Value

        Method

        Select Use template.

        Use template

        Template

        Select the template to be imported.

        -

        Alarm Notification

        Whether to notify users when alarms are triggered. Notifications can be sent as emails or text messages, or HTTP/HTTPS requests sent to the servers.

        You can enable (recommended) or disable Alarm Notification.

        Enable

        Topic

        Name of the topic to which the alarm notification is sent

        If you enable Alarm Notification, you need to select a topic. If no desired topics are available, create one first, whereupon the SMN service is invoked. For details about how to create a topic, see the Simple Message Notification User Guide.

        -

        Trigger Condition

        Condition for triggering the alarm. You can select Generated alarm, Cleared alarm, or both.

        -

    3. On the Specify Rule Name page shown in Table 6, add the alarm rule details. After the configuration is complete, click Finish. The alarm rule is added.
      Table 6 Rule details

      Parameter

      Description

      Example Value

      Name

      Name of the alarm rule. The system generates a name randomly but you can change it.

      alarm-fk0k

      Description

      Alarm rule description. This parameter is optional.

      -