Thanks for your respone Erick! Currently we are trying to keep things simple so we don't use SolrCloud.
I'll give it a look, configuration seems easy, however testing with many clients in parallel seems not so much. Thanks again, Sebastian -----Ursprüngliche Nachricht----- Von: Erick Erickson [mailto:erickerick...@gmail.com] Gesendet: Dienstag, 21. Juni 2016 01:52 An: solr-user <solr-user@lucene.apache.org> Betreff: Re: How many cores is too many cores? Sebastian: It Depends (tm). Solr can handle this, but there are caveats. Is this SolrCloud or not? Each core will consume some resources and there are some JIRAs out there about specifically that many cores in SolrCloud. If your problem space works with the LotsOfCores, start here: https://cwiki.apache.org/confluence/display/solr/Format+of+solr.xml and https://cwiki.apache.org/confluence/display/solr/Defining+core.properties The idea is that if your access pattern is > sign on > ask some questions > go away you can configure that only N cores are loaded at any one time. Theoretically you can have a huge number of cores (I've tested with 15,000) defined, but only say 100 active at a time. There are also options you can specify that cause a core to not be loaded until requested, but not aged out. The 1,500 core case will keep Solr from coming up until all of the cores have been opened, which can be lengthy. But you can define the number of threads that are running in parallel to open the cores.... but the default is unlimited so you can run out of threads (really memory)..... So the real answer is "it's not insane, but you really need to test it operationally and tweak a bunch of settings before making your decision".... Best, Erick On Mon, Jun 20, 2016 at 12:49 PM, Sebastian Riemer <s.rie...@littera.eu> wrote: > Hi, > > Currently I have a single solr server handling 5 cores which differ in the > content they provide. > > However, each of them might hold data for many different clients/customers. > Let's say for example one day there might be 300 different clients each > storing their data in those 5 cores. > > Every client can make backups of his data and import that data back into our > system. That however, makes re-indexing all of his documents in the cores > necessary, which A) is very slow at the moment since fetching the data from > MySQL-DB is slow and B) would slow down searches for all other clients while > the reindexing is taking place, right? > > Now my idea would be: > > What if each client gets his own 5 cores? Then instead of re-indexing I could > simply copy back the solr-index files (which I copied while making the > backup) into his core-directories, right? > > That would lead to about 5 x 300 cores, equals 1500 cores. > > Am I insane by thinking that way? > > Best regards, > Sebastian >
