Word Automation Services Architecture
Last modified: April 01, 2010
Applies to: SharePoint Server 2010
Word Automation Services is a SharePoint Server 2010 service application that has three distinct architectural components:
The Object Model.
The Document Queue.
The Word Automation Services engine.
The document queue manager resides on a back-end application server; it moves incoming requests into the document queue database and sends requests to the Word Automation Services engine for processing. A timer job controls the frequency of conversions and the number of files that are actively being converted. Both the frequency of conversions and the number of files being converted at a given time are configurable by the SharePoint administrator. For example, an administrator might pace Word Automation Services to convert only a small number of files once an hour to avoid interfering with higher-priority tasks.
On a database server, the Word Automation Services engine stores a persistent queue of requested, current, and completed conversions. Storing the queue of conversions on a central database server gives the queue improved scalability, reliability, and availability for tracking large sets of conversions for long periods of time.
The Word Automation Services engine provides an optimized, server-based rendering engine that can use server features, such as the availability of multiple processors. In multiple-server configurations, the Word Automation Services engine balances the load to ensure that no single application server is overloaded by conversion requests.