[Mediawiki-l] Best full-text search engine?

[River Tarnell]

Jim Hu wrote:
> As I understand it, Lucene indexes and stores the indexes into a set  
> of index files that are kept in memory or are swapped in as needed and  
> does not use the backend database that's running the wiki.  
[snip]
> But if Lucene sucks up all your free memory, you could get  
> performance problems outside mySQL.

this is not exactly true.  Lucene will cache some of the index in 
memory, but it's only a small amount.  you can index a very large wiki 
(such as the English Wikipedia) using Lucene without running into memory 
problems.

you will need a reasonable amount of disk space to store the index, of 
course, and more RAM will allow your OS to cache more of the index files 
   itself, which helps performance.

	- river.