Update Attachment Views Immediately ve Duplicate Search Index Information on Thread Copy?

Option to update thread views immediately, or once an hour. If you have a large forum, you will probably want to disable immediate updates, since they are quite server intensive

Setting this option to yes will cause search index information to be copied with each post in the thread. This allows the copied version of the thread to be searchable.

However, on larger boards, this may cause significant delays in copying a thread. If this is a problem for you, we recommend disabling this option.