i am looking for open source libraries which provide high performance faceted search / guided navigation for ecommerce sites
our ecommerce platform is entirely built on .net and so i would prefer libraries which do provide .net apis
performance is of utmost importance here... i checked out sphinx as well as solr but looking for better options as far as performance goes
as per blogs sphinx takes an average of 5 - 6 seconds to perform the first level of faceted search which is unacceptable in a real ecommerce environment
Apache Solr is exactly what you are looking for.
Is a full-fledged search server built using Lucene libs and easily integrable into your .NET application because it has a RESTful API. Comes out-of-the-box with several features such as faceting, caching, scaling, spell-checking, etc.
You can make life easier for your app-to-Solr interaction using the excellent SolrNet library.
Have a look at lucene.net it is a very powerful search engine that can be customised for most search related requirements:
来源：https://stackoverflow.com/questions/4525892/open-source-faceted-search-guided-navigation-for-ecommerce-sites-with-net-api