Workflow Clean up job

By default, Microsoft SharePoint Server 2010 runs a daily Workflow Auto Cleanup job to permanently delete workflow instances and related task entries that still exist 60 days after a workflow is completed or canceled. Workflow history items themselves are not deleted, but the entry point to view them on the status page for a particular instance of a workflow will no longer be available. You can disable the Workflow Auto Cleanup job if you want to keep workflow data available longer. However, as with any SharePoint list, as the workflow history and task lists grow in size, site performance may be compromised. If you are concerned about the size of these lists, keep the Workflow Auto Cleanup job enabled. Whether or not you keep the Workflow Auto Cleanup job enabled, you can create a separate history and task list for each workflow association to distribute items across lists.

To disable automatic workflow cleanup

1. Verify that you have the following administrative credentials:

- To disable automatic workflow cleanup, you must be a member of the Farm Administrators SharePoint group.


2. From the Central Administration Web site, on the Quick Launch, click Monitoring.

3. On the Monitoring page, in the Timer Jobs section, click Review job definitions.

4. On the Job Definitions page, in the Title column, click the Workflow Auto Cleanup link that is associated with the Web application for which you want to disable automatic workflow cleanup.

5. On the Edit Timer Job page, click Disable to disable the Workflow Auto Cleanup feature.

for more information, see

http://technet.microsoft.com/en-us/library/ee662522.aspx