Effects Of Virtual Views On Performance; Compatibility With Existing Applications - Netscape DIRECTORY SERVER 7.0 - DEPLOYMENT Deployment Manual

Virtual Directory Information Tree Views
To clarify any doubts that you have about the effects of views on searching,
understand that if the base of the search is a view and the scope of the search is
not a base, then it is a views-based search. Otherwise, it is a conventional search.
For example, if you perform a search with a base of
entries from the virtual search space will be returned — in fact, no
virtual-search-space search is performed. Views processing occurs only if the
search base is
search does not result in entries from both places (you would would get entries
back from both places if it were a conventional DIT).

Effects of Virtual Views on Performance

The performance of views-based hierarchies is dependent on the make up of the
hierarchy itself and the number of entries in the DIT. In general, you may see a
marginal change in performance (within a few percentage points of equivalent
searches on a conventional DIT) if virtual DIT views are enabled in your
directory. If a search does not invoke a view, then there is no performance impact.
As always, we recommend that before deployment, you must test your virtual
DIT views against expected search patterns and loads.
We also recommend that the attributes used in view filters be indexed if the views
are to be used as general-purpose navigation tools in the organization. Further,
when a sub-filter used by views matches a configured virtual list view index, that
index will be used in views evaluation.
There is no need to tune any other part of the directory specifically for views.

Compatibility with Existing Applications

Virtual DIT views are designed to mimic conventional DITs to a high degree.
Most applications should continue to work without any knowledge that they are
working with views. Except for a few specialized cases, there is no need for
directory users to know that views are being used in a Directory Server
instance—views look and act like conventional DITs.
Certain types of applications may have problems working with a views-enabled
directory. For example:
• Applications that use the DN of a target entry to navigate up the DIT. Such a
type of an application would find that it is navigating up the hiearchy in
which the entry physically exists instead of the view hiearchy in which the
entry was found. The reason for this is that views make no attempt to
84 Netscape Directory Server Deployment Guide • October 2004
ou=Location Views
dc=example,dc=com
(or below). This way, views ensure that your
, then no