Impact of Redgate SQL Search on Server
Answer received from Redgate support:


  Following are answers to your questions:
  
  
  When you load a database in SQL Search, it indexes and stores the
  info on cache for giving search results. To not index specific
  servers, just do not select 'All database' nor pick the database you
  do not want to index in the database filter.
  Whenever you have mode modifications or want the index to be
  refreshed, manually refresh the index from the menu in SQL Search.
  
  
  Hope that helps.
  
  Thanks,   Anuradha Deshpande