Red Hat DIRECTORY SERVER 7.1, Administrator'S Manual

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Tuning Database Performance
Chapter 14 Tuning Directory Server Performance 483
4.
Enter the amount of memory you want to make available for cached entries in
the Memory Available for Cache field.
If you are creating a very large database from LDIF, set this attribute as large as
possible, depending on the memory available on your machine. The larger this
parameter, the faster your database will be created.
When you have finished creating your database, be sure to set this parameter
back to some lower value before you run your server in a production
environment.
Tuning Transaction Logging
Every Directory Server contains a transaction log which logs operations for all the
databases it manages. Whenever a directory database operation such as a write is
performed, the server logs the operation to the transaction log. For best
performance, the directory does not perform the operation immediately. Instead,
the operation is stored in a temporary memory cache on the Directory Server until
the operation is completed.
If the server experiences a failure, such as a power outage, and shuts down
abnormally, the information about recent directory changes that were stored in the
cache is lost. However, when the server restarts, the directory automatically detects
the error condition and uses the database transaction log to recover the database.
Although database transaction logging and database recovery are automatic
processes that require no intervention, you may want to tune some of the database
transaction logging attributes to optimize performance.
CAUTION The transaction logging attributes are provided only for system
modifications and diagnostics. These settings should be changed
only with the guidance of Red Hat Professional Services or Red Hat
Technical Support.
Setting these attributes and other configuration attributes
inconsistently may cause the directory to be unstable.