TDMQ for Apache Pulsar records the complete flow in which a message is sent from the producer to the TDMQ for Apache Pulsar server and then consumed by the consumer, and then displays the flow as a message trace in the console.
A message trace records the entire process in which the message is sent from the producer to the TDMQ for Apache Pulsar server and eventually to the consumer, including the duration of each stage (accurate down to the microsecond), execution result, producer IP, and consumer IP.
Overview
You can use the message query feature in the TDMQ for Apache Pulsar console to view the content, parameters, and trace of a specific message by time or by the message ID displayed in the log. This enables you to:
View the specific content and parameters of the message.
View from which producer IP a message was sent, whether it was sent successfully, and the specific time when it arrived at the server.
View whether the message was persistently stored.
View which consumers consumed the message, whether it was consumed successfully, and the specific time when its consumption was acknowledged.
View the MQ's message processing latency to analyze the performance of the distributed system.
Query Limits
You can query messages in the last 3 days.
You can query up to 65,536 messages at a time.
Prerequisites
You have deployed the producer and consumer services as instructed in the SDK documentation, and they produced and consumed messages in the last 7 days.
2. On the Message Query page, select the region and environment first and then the time range for query. If you know the message ID, you can also enter it for exact match query.
3. Click Query, and the list below will display paginated results.
4. Click View Details in the Operation column of the target message to view its basic information, content (message body), and parameters.
5. Click View Message Trace in the Operation column or select the Message Trace tab on the details page to view the trace of the message. For more information, see Message Trace Query Result Description.
Message Trace Query Result Description
A message trace query result consists of three parts: message production, message storage, and message consumption.
Message production
Parameter
Description
Producer Address
Address and port of the producer.
Production Time
The time when the TDMQ for Apache Pulsar server acknowledged message receipt, accurate down to the millisecond.
Sending Duration
The time it took to send the message from the producer to the TDMQ for Apache Pulsar server, accurate down to the microsecond.
Production Status
Message production success or failure. If the status is Failed, it is generally because the header of the message was lost during sending, and the above fields may be empty.
Message storage
Parameter
Description
Storage Time
The time when the message was persistently stored (TDMQ for Apache Pulsar currently adopts the strong consistency mode where messages will be acknowledged only after being stored, so the storage time is the same as the production time; if in high performance mode, they are different).
Storage Status
Message storage success or failure. If the status is Failed, the message failed to be stored on the disk, which is possibly because the underlying disk was damaged or full. In this case, submit a ticket for assistance as soon as possible.
Message consumption
Message consumption is displayed in the form of a list. TDMQ for Apache Pulsar supports multi-subscription mode, where a message may be consumed by multiple consumers in multiple subscriptions.
The information displayed in the list is as described below:
Parameter
Description
Consumer Group Name
Subscription name.
Consumer Address
Address and port of the consumer receiving the message.
Consumption Time
The time when the TDMQ for Apache Pulsar server received an acknowledgment (ack) from the consumer.
Consumption Duration
Elapsed time between message delivery by the server to the consumer and ack receipt by the server from the consumer, accurate down to the microsecond.
Consumption Status
Message consumption success or failure. This field will be displayed as Failed if the consumer returns a negative-acknowledgment (nack).
