Red Hat Directory Server 8.0 Administrator's Guide

values set on these attributes does not help directory performance. In fact, changing these
attributes may harm overall performance.
The following attributes can be tuned:
• The attributes of the database that manages all other database instances. The Directory
Server Console only shows the databases that contain the directory data and the
NetscapeRoot database. However, the server uses another database to manage these. On
this database, the following attributes can be changed to improve performance:
• The amount of memory to make available for all databases (maximum cache size).
• The maximum number of entries for the server to verify in response to a search request
(look-through limit).
• The amount of memory to make available for import (import cache size).
• The attributes of each database used to store directory data, including the server
configuration data in the NetscapeRoot database. On these databases, to improve
performance, configure the amount of memory to make available for cached entries (memory
available for cache).
To configure the default database attributes that apply to all other database instances:
1. In the Directory Server Console, select the Configuration tab; then, in the navigation tree,
expand the Data Icon, and highlight the Database Settings node.
This displays the Database tabs in the right pane.
1. Select the LDBM Plug-in Settings tab in the right pane.
This tab contains the database attributes for all databases stored on this server.
2. In the Maximum Cache Size field, enter a value corresponding to the amount of memory to
make available for all databases.
3. In the Look-Through Limit field, enter the maximum number of entries for the server to
check in response to a search request.
4. In the Import Cache Size field, enter a value corresponding to the amount of memory in
bytes to make available for import. By default, the value is auto, and 50% of the free memory
is allocated for the import cache. For creating a very large database from LDIF, set this
attribute as large as possible, depending on the memory available on the machine. The
larger this parameter, the faster the database is created.
To keep from setting a limit, type -1 in this text box. If a user binds to the directory as the
Directory Manager, by default the look-through limit is unlimited and overrides any settings
Optimizing Search Performance
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