I suggest first working with a single machine to see if it responds substantially slower with the new version. Just find one of yours and issue it a query that will resolve locally (distrib=false param). Your current collection level queries are internally issuing such queries, and so with a little bit of sleuthing, looking at logs, you can find a shard level query like this. If it's quick then there's some distributed aspect to investigate. But you'll probably see the slowness here, and the problem is better scoped and easier to diagnose. At this point look at timings with debug=timing to see information on each of the components. That may give you a strong clue. If it's in the QueryComponent which actually executes the underlying search then you have some further digging to do. Use a profiler like JVisualVM.
~ David Smiley Apache Lucene/Solr Search Developer http://www.linkedin.com/in/davidwsmiley
