Solr/Lucene fieldCache OutOfMemory error sorting on dynamic field

Question

We have a Solr core that has about 250 TrieIntFields (declared as dynamicField). There are about 14M docs in our Solr index and many documents have

Answer 1

I think you have two options:

1) Add more memory.
2) Force Solr not to use the field cache by specifying facet.method=enum, as per documentation.

There's also a solr-user mailing list thread discussing the same problem.

Unless your index is huge, I'd go with option 1). RAM is cheap these days.