When a site is provisioned SharePoint doesn’t really copy the pages for that site (i.e. default.aspx) into a new database table or directory. These files exist only once on each of the front end web servers. Instead SharePoint creates a reference to those files in the database tables that define the new site. This is called “ghosting”.
When a site is provisioned SharePoint doesn’t really copy the pages for that site (i.e. default.aspx) into a new database table or directory. These files exist only once on each of the front end web servers. Instead SharePoint creates a reference to those files in the database tables that define the new site. This is called “ghosting”. The end result is that each site appears to have it’s own pages but in reality they are shared across all sites that use that site definition. This technique improves performance as SharePoint can retrieve this file from the file system (which is faster than performing a database operation). In addition caching a single file is more efficient than caching files for each site that exists in the farm. The process of ghosting is a huge benefit to SharePoint and performance.