Be sure to test the bloom postings format on your own use case ... in my tests (heavy PK lookups) it was slower.
But to answer your question: I would expect a single segment index to have much faster PK lookups than a multi-segment one, with and without the bloom postings format, but bloom may make the many-segment case faster (just be sure to test it yourself). Mike McCandless http://blog.mikemccandless.com On Tue, Apr 30, 2013 at 1:05 AM, Otis Gospodnetic <otis.gospodne...@gmail.com> wrote: > Hi, > > I was looking at > http://lucene.apache.org/core/4_2_1/codecs/org/apache/lucene/codecs/bloom/BloomFilteringPostingsFormat.html > and this piece of text: > " > A PostingsFormat useful for low doc-frequency fields such as primary > keys. Bloom filters are maintained in a ".blm" file which offers > "fast-fail" for reads in segments known to have no record of the key. > " > > Is this implying that if you are doing PK lookups AND you have a large > index (i.e. slow queries) it may actually be better to keep the index > unoptimized, so whole index segments can be skipped? > > Thanks, > Otis > -- > SOLR Performance Monitoring - http://sematext.com/spm/index.html
