sharepoint 2010 lockManager: Error during locking Web. The Web is locked.

If you try to delete parent item of a child item, from child item's ItemDeleting Event receiver  you start hitting the performance and get the following error:

sharepoint 2010 lockManager: Error during locking Web. The Web is locked.

This scenario occurs if you have Enforce relationship behavior enabled in lookup column of the item getting deleted.

Solution

• Either turn off the Enforce relationship behavior
• Or remove your code from ItemDeleting  to ItemDeleted.