Single or multi-core Solr

We are planning to deploy Solr for searching multiple sites published from common CMS platform.

Th开发者_运维问答ere will be separate sites per language where other languages will mostly have content translated from English.

The search requirements include – keyword highlighting, suggestions (“did you mean?”), stopwords, faceting.

We are evaluating using single core vs per-language multi-core Solr option. What is the recommended approach here?

You need multicore because you cannot do stemming and stopwords on a multilingual database.

Common stopwords in English are "by" and "is" but these words mean "town" and "ice" in many Nordic languages.

If you do multicore, each language can be on its own core with a customized schema.xml that selects the right stemmer, stopwords and protected words. But the same JVM is running it all on the same server, so you are not spending any extra money for servers for one specific language. Then, if the load is too great for one server, you replicate your multicore setup and all of the indexes benefit from the replicas.

You should use the multicore approach. When you want to query multiple cores at once you can use the shards parameter http://wiki.apache.org/solr/DistributedSearch