We are running apache solr through sunspot.
What are the best metrics to use to look at the performance of solr in regards to needs to cluster/scale?
I am looking at monitoring these with nagios or sensu and was planning on just graphing requests per second and response time, then apache bench it and see where the breaking point is.
Are there any specific values I should look at or best practice for monitoring? I've seen a few articles around monitoring with JMX but I dont think I can enable that with sunspot and most nagios plugins seem to just monitor if its up or not and response time, not performance data.