Tri, During replication: * extra disk IO on slaves during replication - worst if you are replicating an optimized index, which can hurt if your index is not RAM resident * the above will consume some of your OS buffer cache, which can hurt * increased network usage - never seen this becoming a real problem, but if you are replicating a large and always optimized index, it might cause problems
After replication: * potentially high CPU usage during the warmup of the new IndexSearcher, depending on warmup queries used, cache warmup settings, etc. Otis ---- Sematext :: http://sematext.com/ :: Solr - Lucene - Nutch Lucene ecosystem search :: http://search-lucene.com/ ----- Original Message ---- > From: Tri Nguyen <tringuye...@yahoo.com> > To: solr-user@lucene.apache.org > Sent: Wed, January 19, 2011 2:56:58 PM > Subject: Re: performance during index switch > > Yes, during a commit. > > I'm planning to do as you suggested, having a master do the indexing and >replicating the index to a slave which leads to my next questions. > > During the slave replicates the index files from the master, how does it >impact performance on the slave? > > Tri > > > --- On Wed, 1/19/11, Jonathan Rochkind <rochk...@jhu.edu> wrote: > > > From: Jonathan Rochkind <rochk...@jhu.edu> > Subject: Re: performance during index switch > To: "solr-user@lucene.apache.org" <solr-user@lucene.apache.org> > Date: Wednesday, January 19, 2011, 11:30 AM > > > During commit? > > A commit (and especially an optimize) can be expensive in terms of both CPU >and RAM as your index grows larger, leaving less CPU for querying, and >possibly >less RAM which can cause Java GC slowdowns in some cases. > > A common suggestion is to use Solr replication to seperate out a Solr index >that you index to, and then replicate to a slave index that actually serves >your queries. This should minimize any performance problems on your 'live' >Solr >while indexing, although there's still something that has to be done for the >actual replication of course. Haven't tried it yet myself. Plan to -- my >plan >is actually to put them both on the same server (I've only got one), but in >seperate JVMs, and on a server with enough CPU cores that hopefully the >indexing won't steal CPU the querying needs. > > On 1/19/2011 2:23 PM, Tri Nguyen wrote: > > Hi, > > Are there performance issues during the index switch? > > As the size of index gets bigger, response time slows down? Are there > > any >studies on this? > > Thanks, > > Tri >