I don't think there is one answer to this problem but at the same time I don't get what Microsofts expectations are.
- Workflows log to the history lists.
- This list shouldn't be assumed or used as an audit list.
- Workflow instances are cleared via a cleanup job (60 day default) but the workflow history list items are not cleared.
This is all good but I've just recently moved a site from SP2007 to SP2010. Due to the workflow history list having 5000+ items in it the UI when viewing details of a workflow shows an exceeded error. This is daft! Even changing the views to limit the items don't help this UI. Only fix is to change the throttling setting in Central Admin for that particular web application.
I want someones take, specifically MS's on this. Is it your intention we should purge this list or something? If so we need to make sure we only do it for lost workflow instances. Why this part of the UI cares for the total items in the list seems daft, surely its a "select * from where instance = guid" (few items returned).
What options do I have. Write some wacky timerjob to purge cleared items or changes a global setting. Eventually ALL workflow history lists will exceed the limit if they are not maintained.
Please give your thoughts. I realise there isn't just one answer.