sharepoint 2010 search result taking more time load for first time

We have internet facing sharepoint 2010 site. When somebody searches one word for the first time then it takes 10+ seconds to load search result after that second time it takes very less time as we did caching. But we want search to display result in less than 5 seconds.

We also do not have too much content in in the index hardly 4000. How can we check where its slowing down? How can we increase performance of search results page for first time search request?

This should be normal after an IISRESET, but if its not, first check out the search query reports to see if it is the actual queries that take time (or something else).

See this link: http:-//blogs.msdn.-com/b/enterprisesearch/archive/2010/06/09/sharepoint-2010-search-dogfood-part-2-query-health-reports.aspx

Pull some data out of that, then maybe look at your search infrastructure if queries are actually slow. It might be something else.