Red Hat Directory Server 8.0 Administrator's Guide

Before creating new indexes, balance the benefits of maintaining indexes against the costs.
• Approximate indexes are not efficient for attributes commonly containing numbers, such as
telephone numbers.
• Substring indexes do not work for binary attributes.
• Equality indexes should be avoided if the value is big (such as attributes intended to contain
photographs or passwords containing encrypted data).
• Maintaining indexes for attributes not commonly used in a search increases overhead without
improving global searching performance.
• Attributes that are not indexed can still be specified in search requests, although the search
performance may be degraded significantly, depending on the type of search.
• The more indexes you maintain, the more disk space you require.
Indexes can become very time-consuming. For example:
1. The Directory Server receives an add or modify operation.
2. The Directory Server examines the indexing attributes to determine whether an index is
maintained for the attribute values.
3. If the created attribute values are indexed, then the Directory Server generates the new index
entries.
4. Once the server completes the indexing, the actual attribute values are created according to
the client request.
For example, the Directory Server adds the entry:
dn: cn=John Doe, ou=People,dc=example,dc=com
objectclass: top
objectClass: person
objectClass: orgperson
objectClass: inetorgperson
cn: John Doe
cn: John
sn: Doe
ou: Manufacturing
ou: people
telephonenumber: 408 555 8834
description: Manufacturing lead for the Z238 line of widgets.
The Directory Server is maintaining the following indexes:
Chapter 10. Managing Indexes
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