: Is it just that the cache size needs to be bigger then the number of : distinct values for a field?
basically yes, but the cache is going to be used for all filters -- not just those for a single facet (so your cache might be big enough that faceting on fieldA or fieldB is fine, but if you facet on both you'll get performance pains) : If so, it would be nice to add an /admin page that lists each field, : the distinct value count and a green/red box showing if the current : configuration will facet quickly. This could be a good place to : suggest a good configuration for the data in your index. that reminds me of an idea i had way back when for a Solr sanity checker tool that would inspect your schema, index, and logs of sample queries and point out things that didn't seem to make any sense, ie: String fields that don't omitNorms, sorting on a tokenized field, or a non-sortable int/float fields that werre multivalued but didnt' seem like they needed to be (because every doc only had one value) etc... -Hoss
