If message consumption exceptions occur, you can check the consumer status in the Message Queue for Apache RocketMQ console for troubleshooting. You can view information about consumer instances in a group identified by a group ID, and information about a single consumer instance in this group.

Scenarios

Consumer status information includes online status, subscription, consumption TPS, message accumulation amount, and JStack information. It is often used in the following troubleshooting scenarios:

  • Subscription inconsistency
  • Message accumulation
    • Symptom: On the Consumer Status, the Real-time Accumulated Messages field of a group ID displays a value that is higher than expected.
    • Solution: For more information about how to handle message accumulation, see How to handle accumulated messages.

View comprehensive information about a group ID

To view the comprehensive information about the consumer instances under a specific group ID, perform the following steps:

  1. Log on to the Message Queue for Apache RocketMQ console. In the top navigation bar, select the region, such as China (Hangzhou).
  2. On the Instances page, find the target instance and click Details in the Actions column.
  3. In the left-side navigation pane, click Groups.
  4. On the Groups page, find the target group ID and click Consumer Status in the Actions column.

    The result is shown in the following figure.

    Consumer status
Table 1. Fields
Field or icon Description
Online status icon
  • This field displays Online as long as one of the consumer instances under the group ID is online. At the bottom of the page, the Connection Information section displays the information about online consumer instances.
  • If all the consumer instances under the group ID are offline, this field displays Offline, and the Connection Information section displays nothing.
Subscription Consistency This field indicates whether the subscription information of all the consumer instances under the group ID is consistent. For more information about subscription consistency, see Subscription consistency.
Real-time Consumption Rate The total transactions per second (TPS) at which messages are received by the consumer instance group under the group ID. Unit: messages/s.
Real-time Message Accumulation The total number of messages that are not consumed by the consumer instance group under the group ID.
Latest Consumption Time The last time when the consumer instance group under the group ID consumed a message.
Latency The difference between the production time of the earliest unconsumed message in the consumer instance group under the group ID and the current time.

View information about a single consumer instance under a specific group ID

If the online status of the group ID is Online, you can view the information about each online consumer instance under the group ID in the Connection Information section, including the client ID, host or public IP address, current process ID, and message accumulation amount.

View more information

You can also click Details in the Description column to view more information about a specific consumer instance, including the number of consumption threads, consumption start time, subscription, and message consumption statistics, as shown in the following figure.

Connection detailsView JStack information
To view the JStack information of the current process for a specific consumer instance, find the target consumer instance and click Stack Information in the Stack Information column. The displayed information is shown in the following figure.JStack

More information

If you have set metrics and received notifications about message accumulation, see What should I do if I receive a message accumulation alert.