No, Solr doesn't load the entire index in memory. I think you'll find Uwe's blog most helpful on this matter:
http://blog.thetaphi.de/2012/07/use-lucenes-mmapdirectory-on-64bit.html On Thu, Feb 13, 2014 at 12:27 AM, Joshi, Shital <shital.jo...@gs.com> wrote: > Does Solr4 load entire index in Memory mapped file? What is the eviction > policy of this memory mapped file? Can we control it? > > _____________________________________________ > From: Joshi, Shital [Tech] > Sent: Wednesday, February 05, 2014 12:00 PM > To: 'solr-user@lucene.apache.org' > Subject: Solr4 performance > > > Hi, > > We have SolrCloud cluster (5 shards and 2 replicas) on 10 dynamic compute > boxes (cloud). We're using local disk (/local/data) to store solr index > files. All hosts have 60GB ram and Solr4 JVM are running with max 30GB heap > size. So far we have 470 million documents. We are using custom sharding and > all shards have ~9-10 million documents. We have a GUI sending queries to > this cloud and GUI has 30 seconds of timeout. > > Lately we're getting many timeouts on GUI and upon checking we found that all > timeouts are happening on 2 hosts. The admin GUI for one of the hosts show > 96% of physical memory but the other host looks perfectly good. Both hosts > are for different shards. Would increasing ram of these two hosts make these > timeouts go away? What else we can check? > > Many Thanks! > > -- Regards, Shalin Shekhar Mangar.
