ESE databases use log files to accept, track, and maintain data. To enhance performance, all transactions are written first to log files and memory, and then to the database file. The checkpoint file tracks the transaction log entries that have been committed to the database. During an ordinary shutdown of the Microsoft Exchange Transport service, uncommitted database changes that are found in the transaction logs are always committed to the database.

Circular logging is used for the message queue database and the IP filter database. This means that the history of committed transactions that are found in the transaction logs is not maintained. Any transaction logs that are older than the current checkpoint are immediately and automatically deleted. Therefore, the transaction logs cannot be replayed for message queue database recovery or IP filter database recovery from backup.

The shared ESE database configuration options are available in the EdgeTransport.exe.config application configuration file that is located in the C:\Program Files\Microsoft\Exchange Server\Bin directory. The EdgeTransport.exe.config file is an XML application configuration file that is associated with the EdgeTransport.exe file. EdgeTransport.exe and MSExchangeTransport.exe are the executable files that are used by the Microsoft Exchange Transport service. This service runs on every Hub Transport server or Edge Transport server. Changes that are saved to the EdgeTransport.exe.config file are applied after the Microsoft Exchange Transport service is restarted. If a configuration option is missing or is present and contains the default value, the default value is enforced.

The following example shows the typical structure of the EdgeTransport.exe.config file:

<configuration>

<runtime>

<gcServer enabled="true" />

</runtime>

<appSettings>

<add key=" Configuration Option " value=" Value " />

...

</appSettings>

</configuration>

You can add new configuration options or modify existing configuration options in the <appSettings> section. Many configuration options available are completely unrelated to the shared ESE database options. Any configuration options that don't involve the shared ESE database options are outside the scope of this topic.

Note:
The parameter names in the <add key=../> section are case sensitive.

For information about the message queue database parameters that are available in the EdgeTransport.exe.config file, see Managing the Queue Database.

Table 1 shows the shared ESE database configuration options that are available in the EdgeTransport.exe.config file.

Table 1   Shared ESE database configuration options

For more information about how performance can be affected by changing the value of the DatabaseMaxCacheSize parameter, see the Exchange Server Team Blog article, New maximum database cache size guidance for Exchange 2007 Hub Transport Server role.

Note:
The content of each blog and its URL are subject to change without notice. The content within each blog is provided "AS IS" with no warranties, and confers no rights. Use of included script samples or code is subject to the terms specified in the Microsoft Terms of Use.

Remember that the message queue database and the IP filter database are completely isolated from one another. The ESE database files don't share database files, transaction logs, or caches. The shared configuration options apply to each database and its supporting infrastructure. For example, when you set the DatabaseMaxCacheSize parameter, you are at the same time setting the maximum cache size for the message queue database and the IP filter database.