Using Solr 3.4.0. That changelog actually says it should reduce memory usage for that version. We were on a much older version previously, 1.something. Norms are off on all fields that it can be turned off on. I'm just hoping this new version doesn't have any leaks. Does FastLRUCache vs LRUCache make any memory difference?
You can add JVM parameters to better trace the heap usage with -XX:+PrintGCDetails -verbose:gc -Xloggc:/your/gc/logfile
Graphing that over time may help you see if you are constantly near the limit, or only at particular times, and try to correlate that to other operations (insertions, commit, optimize, ...)
-- André Bois-Crettez Search technology, Kelkoo http://www.kelkoo.com/
