Red Hat Directory Server 8.0 Administrator's Guide

in the Idle Timeout text box.
To keep from setting a limit, type zero (0) in this text box.
5. Set the maximum number of file descriptors available to the Directory Server in the Max
Number of File Descriptors text box. For more information on this parameter, see the
Directory Server Configuration, Command, and File Reference.
For a better understanding of how these parameters impact the server's search performance,
see Section 1, “About Indexes”.
2. Tuning Database Performance
This section is divided into the following parts which describe methods for tuning database
performance:
• Section 2.1, “Optimizing Search Performance”
• Section 2.2, “Tuning Transaction Logging”
• Section 2.3, “Changing the Location of the Database Transaction Log”
• Section 2.4, “Changing the Database Checkpoint Interval”
• Section 2.5, “Disabling Durable Transactions”
• Section 2.6, “Specifying Transaction Batching”
2.1. Optimizing Search Performance
Improve server performance on searches by tuning database settings. The database attributes
that affect performance mainly define the amount of memory available to the server. There are
two kinds of database caches, one for the default database cache and the other for the entry
cache. The server has one default database cache per server, and one entry cache per
database.
To improve the cache hit ratio on search operations, increase the amount of data that the
Directory Server maintains in the database cache. Do this by increasing the cache size. The
maximum values that can be set for these attributes depends on the amount of real memory on
the machine. Roughly, the amount of available memory on the machine should always be
greater than sum total of the default database cache size and sum of each entry cache size.
Use caution when changing these two attributes. The ability to improve server performance with
these attributes depends on the size of the database, the amount of physical memory available
on the machine, and whether directory searches are random (that is, if the directory clients are
searching for random and widely scattered directory data).
If the database does not fit into memory and if searches are random, attempting to increase the
Chapter 15. Tuning Directory Server Performance
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