LUCENE-3841 (and several threads on the list)
Currently each SnowballStemmer is pretty heavy since each instance also contains a bunch of Among objects (part of the stemming rules).
This normally shouldnt be a problem, except it seems challenging
for tomcat users to tune their threadpools (basically they are creating
lots of tokenstreams, so lots of SnowballStemmers)
Newer snowball just makes these static, and its easy enough to just
regenerate so these aren't so heavy, it doesnt fix the real problem but it also doesn't hurt.