Topic Last Modified: 2006-04-20
The Microsoft® Exchange Server Analyzer Tool includes a performance data collection engine that is used to query performance counter objects on computers that are running Exchange 2000 Server or Exchange Server 2003. The performance data collection engine collects data from the Local Queue Length performance counter of the SMTP Server performance object to analyze performance data.
If the Exchange Server Analyzer determines that the Local Queue Length counter has exceeded the peak value of 1000 during the sample time slice, the Exchange Server Analyzer displays an error.
The SMTP Server\Local Queue Length counter indicates the number of messages in the Simple Mail Transfer Protocol (SMTP) queue for local delivery to the Microsoft Exchange Information Store service. SMTP local queue data (Mailroot directory) is temporarily held in the storage device while it is being processed by Exchange Server. This design prevents the data from being lost if the server fails. For example, when a destination server is unreachable, the messages that should be routed to that server will be stored on the local server queue directory until they can be delivered.
This error indicates a performance issue or outages on the server, because the server can no longer deliver the incoming mail in a timely manner. The following conditions can cause this delay:
- The Active Directory® directory service is not being consulted
- Messages are not being handed off promptly for local delivery
- Databases (mailbox stores and public folder stores) have been
- To resolve this issue, take the following steps:
- Make sure all databases (mailbox stores and public folder
stores) are mounted.
- Identify the source of the performance bottleneck. A
performance bottleneck may be CPU, disk, network, or memory related
and can be caused by an increase in load to the server or
insufficient server resources. Use the Performance Monitor
(Perfmon.msc) tool to determine whether the bottleneck is caused by
an increased load on the server or whether the server is
undersized. If the server load has increased, identify the source
of the load and reduce it. If the server has insufficient
resources, increase the necessary resources or move users off the
- Monitor external dependencies, such as the Active Directory
directory service, for performance issues and troubleshoot and
correct as necessary.
For More Information
- For more information about SMTP transport tuning, see "SMTP
Transport Tuning" in the Performance and Scalability Guide for
Exchange Server 2003 (http://go.microsoft.com/fwlink/?LinkId=47576).
- For more information about troubleshooting mail flow issues,
see Microsoft Knowledge Base article 823489, "How to use Queue
Viewer to troubleshoot mail flow issues in Exchange Server 2003"
- For more information about troubleshooting transport issues,
see Microsoft Knowledge Base article 257265, "General
troubleshooting for transport issues in Exchange 2000 Server and in
Exchange Server 2003" (http://go.microsoft.com/fwlink/?linkid=3052&kbid=257265).
- For more information about processor bottlenecks, see Processor
- For more information about disk Bottlenecks, see Disk Bottleneck
- For more information about Exchange Server performance, see the
Performance and Scalability Guide for Exchange Server 2003
- For more information about troubleshooting Exchange Server
performance issues, see Troubleshooting Microsoft Exchange
Server Performance (http://go.microsoft.com/fwlink/?LinkId=47588).
- For more information about how to move user mailboxes to reduce
server load, see Move User Mailboxes to