Microsoft Sharepoint Products and Technologies Resource Kit eBook

Chapter 21: The Architecture of the Gatherer 595
2. On the Configure Search And Indexing page, in General Content Settings
and Indexing Status, click Include File Types.
3. On the Include File Types page, click Add File Type.
4. On the Add File Type page, in the File Extension box, type the file name
extension for the file type that you want to add to the list of file types for the
content index.
5. Click OK.
The Architecture of Index Updates
Once the content of a site and the content sources are indexed, the index needs to
be updated to maintain accuracy. When you add documents to the portal site or
modify existing documents, SharePoint Portal Server modifies the index to include
the changes. When an index is updated, it follows the same process of breaking
down the information in documents that it does when the index is first created.
However, the changes are not immediately merged into the master index.
The process of merging changes into the master index is highly resource intensive.
To make this process more efficient. SharePoint Portal Server merges only a
group of changes into the master index. Until there are enough changes to merge
into the master index, they are saved in separate lists and indexes. Figure 21-2
shows the different lists and indexes involved in the update process.
Document Set
Changes to the document
set are indexed and saved
into word lists
Word lists are
combined into
shadow indexes
Word List Shadow Index
Master Index
Word lists and shadow indexes
are integrated into the master
index with a master merge
F21XR02
Figure 21-2 The creation of word lists and shadow indexes prior to doing a master merge
in the SharePoint Portal Server Search service