I wrote a query that replaced roughly 470153 text nodes with an element that had two namespaces declared on it. It ran for several hours.

I didn't need or want these namespaces, they were in the original source. I rewrote the query to remove the namespaces from these nodes before replacing the text node. I don't know how quickly it ran, but I think not more than 15 minutes, the first time I checked on it, it had already finished. I made no other changes to the query.

Is this surprising? Or is this a general lesson about performance and updates that add namespaces low down in the hierarchy? Or ...

Jonathan