Mac Srv: Objects, Large Mail Data Files, & Server Performance (119044)


The information in this article applies to:

  • Microsoft Mail for AppleTalk Networks 3.0
  • Microsoft Mail for AppleTalk Networks 3.1
This article was previously published under Q119044

SUMMARY

The Microsoft Mail for AppleTalk Networks data file can be large for two reasons: many objects and/or many enclosures.

Run the Mail Network Administrator program and run the Server Usage report to get an idea of what percentage of the data file is made up of enclosures. If the data file is mostly made up of large enclosures, server performance should not be hampered.

The Microsoft Mail data file can contain up to 65,535 objects. AppleTalk Mail uses an object to represent the many parts of mail: each message, enclosure, form, user information, information about other Mail servers, group lists, gateway names, gateway resources, etc. The Mail server keeps track of all of these objects by keeping a map in memory of where these objects are on disk.

A large number of objects can affect the performance of the Mail server. When a Mail data file has a large number of objects, the map in memory is also large (one entry for each object). For any disk access, the server must search the map to find where the requested object is on disk. Even though the map is a binary tree, a large number of objects can slow down this searching process. Virtually every request by a workstation or another server on the network requires the server to access the hard disk.

MORE INFORMATION

Because of shared objects, it is not possible to tell exactly how many objects are contained in a Mail data file. A rough estimate can be made by adding the following numbers together:

  1. Total number of messages
  2. Total number of enclosures
  3. If on a gateway server, add one for every gateway recipient defined in the Gateway Recipients screen per gateway.


If this number is less than 60,000, then the server has not reached the limit on the number of objects. If this number is greater than 65,535, then the server still may not have reached the limit on the number of objects, because messages and objects to multiple recipients are shared. However, steps should be taken to reduce the number of messages and enclosures in the Mail data file.

These steps would include:

  1. Deleting mail older than X number of days old.
  2. Moving users to other servers.
  3. Having users move messages to local storage.
NOTE: The above numbers are a rough estimate based on experience by Mail Product Support. 3.00 3.10
Modification Type:MajorLast Reviewed:10/30/2003
Keywords:KB119044
©2003 Microsoft Corporation. All rights reserved.