From: Charlie Hull [char...@flax.co.uk]: > We've just found a very similar issue at a client installation. They have > around 27 million documents and are faceting on fields with high > cardinality, and are unhappy with query performance and the server hardware > necessary to make this performance acceptable.
I have done some testing on distributed non-pivot faceting and found that the fine-counting of the top-X terms can be very expensive for some queries. It seems that for fc-faceting with Strings it is markedly faster (and non-filter-cache-blowing) to do a standard faceting call and extract the relevant term counts for fine-counting instead of processing the requested terms one at a time. It seems that the same principle might apply to pivot faceting. There's a write-up with graphs at http://sbdevel.wordpress.com/2014/08/26/ten-times-faster/ - Toke Eskildsen
