When you provision Enterprise search on SharePoint Server 2013 (via powershell!). It will install all the major components onto that first server.

To scale it out a bit, we decided to push out some of these components to the WFE. In particular the Query Processing and ine the partiition index.

This should help your users get a better response from the search feature and utilises your WFE in a better way. I f you have bigger search requirements then it maybe an idea to put the partition on its own server.

There are many ways of skinning this particular cat, but I hope this at least makes it easier for you to not overload your app server with mundane requests. This is what your WFE is for! to server the users!

Query Processing

Move Index Partition