Mailbox Assistants Test

The Microsoft Exchange Mailbox Assistant service provides functionality for Calendar Attendant, Resource Booking Attendant, Out of Office Assistant, and Managed Folder Mailbox Assistant.

The Exchange Assistants can be either event-based Assistants or time-based Assistants. The event-based Assistants start to process mailboxes on the occurrence of an event, such as on a change of Out-of-Office (OOF) information in one or more mailboxes. The time-based Assistants process the mailboxes periodically. Each time-based Assistant deploys an Assistants Driver that periodically checks whether the current time is within in a specified time window. When the current time reaches the specified time window, the Assistants Driver invokes the corresponding time-based Assistant. The time-based Assistant then obtains a list of mailboxes from the database and starts to process them.

To determine whether there are any mailbox assistant-related issues, use the Mailbox Assistants test.

Target of the test : An Exchange server 2000/2003/2007

Agent deploying the test : An internal agent

Outputs of the test : One set of results for the Mailbox server being monitored.

Configurable parameters for the test
Parameters	Description
Test Period	How often should the test be executed.
Host	The IP address of the Mailbox server.
Port	The port number through which the Mailbox server communicates. The default is 6001.
IsPassive	If the value chosen is Yes, then the Exchange server under consideration is a passive server in an Exchange cluster. No alerts will be generated if the server is not running. Measures will be reported as "Not applicable" by the agent if the server is not up. This parameter can be ignored while configuring this test for a managed “Exchange Mailbox” server.

Measurements made by the test
Measurement	Description	Measurement Unit	Interpretation
Events waiting to be processed by assistants	Indicates the current number of events in the in-memory queue waiting to be processed by the assistants.	Number	Ideally, the value of this measure should be low at all times. High values may indicate a performance bottleneck.
Events processed rate by Exchange assistants	Indicates the number of events processed per second.	Events/Sec	While sporadic dips in this value can be ignored, a consistent decrease could be a cause for concern, and may warrant a thorough investigation.
Events polled by Exchange assistants	Indicates the number of events polled per second.	Events/Sec
Delay between polling and event creation	Indicates the current latency between when the most recent MAPI event was polled and when the event was created.	Secs
Event queueing time - average	Indicates the average time (in seconds) that the event lives in the dispatcher queue.	Secs	Ideally, the value of this measure should be low. A very high value indicates that there are many events in queue with long waiting times. This in turn indicates a processing bottleneck.
Event processing time - average	Indicates the average time (in seconds) that the assistants took for processing events.	Secs	Ideally, the value of this measure should be low. A very high value indicates that there are many events in queue with long waiting times. This in turn indicates a processing bottleneck.
Queue size of event dispatchers - average	Indicates the average queue size of event dispatchers.	Number	A gradual but steady increase in the value of this measure over time, could indicate a problem with the dispatcher queue.
Mailbox processing time - average	Indicates the average processing time of mailboxes for time-based assistants.	Secs	A low value is typically desired.
Failed event dispatchers	Indicates the percentage of Event Dispatchers that are in failure mode, currently.	Percent
Mailboxes processed	Indicates the rate at which time-based assistants processed mailboxes.	Operations/Sec
Threads in use from the CLR thread pool	Indicates the current number of Threads used from the CLR thread pool.	Number