On 10/7/2015 4:03 AM, Eric Torti wrote: > I'm sorry to diverge this thread a little bit. But could please point me to > resources that explain deeply how this process of OS using the non-java > memory to cache index data? > >> Whatever RAM is left over after you give 12GB to Java for Solr will be >> used automatically by the operating system to cache index data on the >> disk. Solr is completely reliant on that caching for good performance. > > I'm puzzled as to why the physical memory of solr's host machine is always > used up and I think some resources on that would help me understand it.
Toke's reply is excellent, and describes the situation from Lucene's perspective. Solr is a Lucene program, so the same information applies. Here's more generic information on how the OS uses memory for caching for most programs: https://en.wikipedia.org/wiki/Page_cache Note that some programs, like MySQL and Microsoft Exchange, skip the OS cache and take care of caching internally. Thanks, Shawn
