If you want to find out the overall latency for e-mails flowing in your Exchange 2007 organization, you can use the MSGAnalyzer tool from Microsoft or you have to check when an e-mail first reached your servers, check when it was delivered to the recipient’s mailbox and then calculate the time difference.
The good news is that with Exchange 2010 this is much, much easier as this information is saved in the Message Tracking Logs. When a HUB server delivers a message (through the Store Driver) it generates a DELIVER event which contains the TimeStamp of when the message was delivered (as with Exchange 2007) but now it also includes the MessageLatency which is the difference between the original arrival time of the message and this timestamp.
So, if you want to check the latency for all the e-mails arriving in your organization, simply use the a cmdlet similar to the following one:
Get-TransportServer | Get-MessageTrackingLog -ResultSize Unlimited -Start “03/26/2012” -EventID DELIVER | FT MessageLatency
Which will give you a TimeSpan value like “00:00:03.8130000” which means the e-mail took almost 4 seconds to be delivered.
If you are just interested in a particular day and also want to know which HUB server delivered it each message:
Get-TransportServer | Get-MessageTrackingLog -ResultSize Unlimited -Start “03/26/2012” -End “03/27/2012″ -EventID DELIVER | Select TimeStamp, ClientHostname, @{Label=”LatencyMil”; Expression={$($_.MessageLatency).TotalMilliseconds}} | Export-Csv Latency_20120326.csv -NoTypeInformation
Note that this time we are printing the TotalMilliseconds it took to deliver each message which makes it easier to calculate the average for the day in Excel.
