Finger print search time taking around 3 seconds

[nikhil....@ignite.world]

We are facing high fingerprint match solr query time. Following is our setup Info:

• echonest/echoprint-server running on single node (solr 1.0) running on amazon ec2 instance m3.2x large box with 30G RAM & 8 cores
  
• 2.5 million tracks(segment count 19933333) ingested with solr 1.0 index size around 91G.
  
• Applied optimization HashQueryComponent.java https://github.com/playax/echoprint-server/commit/706d26362bbe9141203b2b6e7846684e7a417616#diff-f9e19e870c128c0d64915f304cf43677
  
• Also tried to capture stats of eval method, some of the loop iterations of sequential subreader of index reader took more than 1 second to iterate over all the terms.
  
• Tried with more RAM (120 GB) and loaded entire index into RAM via cat indexpath/* >> /dev/null but no improvement in query time. Also tried testing after integrating Lucene’s MMapDirectory into solr 1.0, still query time between 2 and 3 seconds

Any suggestions or pointers in the right directions will be very helpful.