PreEmptive Analytics Data Hub User Guide

RabbitMQ Monitoring

Detailed information about the queues used by the Data Hub can be seen in the RabbitMQ management console.

WARNING: the management console also allows functional alteration of components of RabbitMQ, which could adversely affect the Data Hub or cause data loss. To prevent unwanted changes to RabbitMQ, you may want to create a monitoring user.

Note: The management console updates its display every 5 seconds, at the fastest, so queue state as shown in the console may be inaccurate. Additionally, rates listed are not guaranteed to accurately reflect the state of the Data Hub, depending on load and configuration. To mitigate these issues, use the the WMI Counters to monitor state, instead.

Queues Page

To access the management console's queues page:

  1. Using a web browser, browse to http://localhost:15672/#/queues.
  2. Log in using an account with monitoring privileges.
  3. If not expanded, expand the All queues section.

This page displays all the queues used by this installation of RabbitMQ. All queues related to the Data Hub begin with the pahub. prefix. If another application is using this instance of RabbitMQ (such as the PreEmptive Analytics Workbench), there may be additional queues for that product.

The pahub.endpoint queue is the Endpoint Queue, where the Endpoint Web Service queues all incoming messages for the Dispatch Service to process. Other queues represent destination-specific queues; for instance, pahub.commercial ri_offline is the Offline Queue for a destination named Commercial RI.

The columns in this display are:

  • Overview
    • Name
      • The name of the queue.
    • Status
      • Active if the Data Hub is currently connected to the queue.
      • Idle otherwise (mouse-over to see how long since the queue was last active).
    • Exclusive, Parameters, and Policy are not relevant to this application.
  • Messages
    • Ready
      • The number of messages queued but not actively being processed.
    • Unacked (unacknowledged)
      • The number of messages queued and being processed by the Dispatch Service.
    • Total
      • The number of messages queued.
  • Message rates
    • incoming
      • The rate, in messages per second, of enqueue operations onto the queue.
    • deliver / get
      • The rate, in messages per second, of movement operations to the Unacked state.
    • ack
      • The rate, in messages per second, of dequeue operations from the queue.

Note: These rates are only from the perspective of the queues themselves. Some operations by the Dispatch Service involve dequeuing and then re-queueing messages to a different queue (such as when a message from the endpoint queue is routed to an offline destination) or the same queue (such as after a retry of a message). To see the rates at which messages are actually being dispatched, use the WMI counters.

Queue Detail Page

More detailed information for a particular queue can be found by clicking on the queue name from the queues page. This page is divided into sections. Of them, only the Overview section is relevant to monitoring - the other sections either provide no useful information for this application, or actively modify the queue rather than just observing it, often in potentially dangerous ways.

The Overview section is further divided into three subsections:

  • Queued messages
    • Graph of several counts of messages in the queue, similar to the Messages fields on the queues page.
    • The way this data is presented can be changed by clicking on the text in parentheses after the graph title. This affects how the queued messages data will be displayed on all queue detail pages.
  • Message rates
    • Graph of several message rates, similar to the Message rates fields on the queues page.
    • The way this data is presented works similarly to the previous subsection.
  • Details
    • Status
      • Active if the queue is currently connected to by another part of the Data Hub.
      • Idle otherwise; time since last active will be displayed.
    • Memory
      • The amount of memory taken up by the queue.
    • Parameters, Policy, Exclusive Owner, and Consumers are not relevant to this application.

Data Hub Version 1.5.0. Copyright © 2015 PreEmptive Solutions, LLC