eG Monitoring
 

Measures reported by BTMsgHostTest

The first time you configure a BizTalk server, the following set of tables are created in the MessageBox database for a BizTalkServerApplicationHost:

  • The BizTalkApplicationQ
  • The BizTalkServerApplicationQ_Suspended
  • The BizTalkServerApplicationQ_Scheduled
  • The InstanceStateMessageReferences_BizTalkServerApplication

BizTalk uses these tables to keep references of all the messages that are "live" in the system . That is: Messages with active subscriptions, suspended messages, and awaiting messages associated to each host.

The word references implies that the host tables are only pointers to the Spool table, but the real messages itself are saved in another set of tables ( messageparts, parts and fragments).

This test monitors the number of message references in the host queue tables, and proactively alerts administrators to the following:

  • A sudden/consistent increase in the length of the host queues
  • Too many message references in the suspended queue

The measures made by this test are as follows:

Measurement Description Measurement Unit Interpretation
HostQueueInstance Indicates the number of message references in the instance state queue of this host instance. Number The State Queue table holds the list of messages that have been processed by an instance but will be needed later. When an orchestration uses the State Queue, it is usually because the orchestration performed some operations on a message, persisted the message, and might need the message later. This is normal operation, and you should take this into account when determining correct sizing of the State Queue
HostQueueNumber Indicates the number of instances of the host queue for this host instance. Number  
HostQueueLength Indicates the number of messages in the host queue of this host instance. Number Generally, this queue should not grow too large. The length of the queue indicates the number of messages waiting to be processed. A large number means you could have a backlog.
HostQueueSuspended Indicates the total number of suspended messages for this host instance. Number When a message gets suspended it remains in the messagebox until resume or terminate actions occurs. So, if the suspended queue keeps growing, the performance of the BizTalk server will continue to get affected. A suspended message can be due, for example, to parsing errors, serialization errors, failed transmissions, or the inability to find a a subscription.