About Optimized Verity Databases; Performance Tuning Options - MACROMEDIA COLDFUSION MX 61 - CONFIGURING AND ADMINISTERING COLDFUSION MX Manual

You can safely squeeze deleted documents for a collection at anytime, because the mkvdk utility
ensures that the collection is available for searching and servicing through its self-administration
features. The application does not need to temporarily disable a collection to squeeze deleted
documents, because when a squeeze request is made, the mkvdk utility assigns a new revision
code to the collection. After a squeeze has occurred, the next time the application accesses the
collection, the Verity engine notifies the application that dramatic changes have been made, and
points the application to the new collection data.
Squeezing deleted documents out of a collection is a significant update to the collection. If users
are reviewing search results at the time when squeezing occurs, the search results might be
invalidated after the squeeze operation.

About optimized Verity databases

The Verity database (VDB) is the fundamental storage mechanism responsible for supporting
dynamic access to documents in collections. A VDB consists of simple tables with rows and
columns that relate to each other by row position. VDB tables are not relational, and their
architecture supports quick and efficient searching over textual data. A VDB consists of segments
that are packed into a single file. One of the advantages of having one packed VDB file is
optimized search performance. The fewer files that need to be opened during search processing,
the faster the search performance.
The VDB optimization option optimizes the packing of a collection's VDBs. When VDBs are
built during normal indexing operations, the segments are not stored sequentially in the one-file
VDB file system. As a result of VDB optimization, performance can be improved by reserializing
the packed segments in the VDBs so that all segments are contiguous, and VDBs can grow in size.
Optimized VDBs can grow up to 2 gigabytes in size, as opposed to the maximum 64 megabytes
for an unoptimized one.
Using this option might degrade your indexing performance when certain indexing modes are set
for the collection.

Performance tuning options

The mkvdk utility provides performance tuning options, as the following table describes:
Option
-maxfiles num
-diskcache num
100 Chapter 8: Managing Collections with the mkvdk Utility
Description
Sets the maximum number of files that the mkvdk utility can have open at once.
The default is 50.
Sets the size of the mkvdk disk cache in kilobytes. The default is 128.