Hi Scott, There is no definite answer - it depends on your documents and query patterns. Sharding does come with an overhead but also allows Solr to parallelise search. Query latency is usually something that tells you if you need to split collection to multiple shards or not. In caseIf you are ok with latency there is no need to split. Other scenario where shards make sense is when routing is used in majority of queries so that enables you to query only subset of documents. Also, there is indexing aspect where sharding helps - in case of high indexing throughput is needed, having multiple shards will spread indexing load to multiple servers. It seems to me that there is no high indexing throughput requirement and the main criteria should be query latency. Here is another blog post talking about this subject: http://www.od-bits.com/2018/01/solrelasticsearch-capacity-planning.html <http://www.od-bits.com/2018/01/solrelasticsearch-capacity-planning.html>
Thanks, Emir -- Monitoring - Log Management - Alerting - Anomaly Detection Solr & Elasticsearch Consulting Support Training - http://sematext.com/ > On 14 Mar 2018, at 01:01, Scott Prentice <s...@leximation.com> wrote: > > We're in the process of moving from 12 single-core collections (non-cloud > Solr) on 3 VMs to a SolrCloud setup. Our collections aren't huge, ranging in > size from 50K to 150K documents with one at 1.2M docs. Our max query > frequency is rather low .. probably no more than 10-20/min. We do update > frequently, maybe 10-100 documents every 10 mins. > > Our prototype setup is using 3 VMs (4 core, 16GB RAM each), and we've got > each collection split into 2 shards with 3 replicas (one per VM). Also, > Zookeeper is running on each VM. I understand that it's best to have each ZK > server on a separate machine, but hoping this will work for now. > > This all seemed like a good place to start, but after reading lots of > articles and posts, I'm thinking that maybe our smaller collections (under > 100K docs) should just be one shard each, and maybe the 1.2M collection > should be more like 6 shards. How do you decide how many shards is right? > > Also, our current live system is separated into dev/stage/prod tiers, not, > all of these tiers are together on each of the cloud VMs. This bothers some > people, thinking that it may make our production environment less stable. I > know that in an ideal world, we'd have them all on separate systems, but with > the replication, it seems like we're going to make the overall system more > stable. Is this a correct understanding? > > I'm just wondering anyone has opinions on whether we're going in a reasonable > direction or not. Are there any articles that discuss these initial > sizing/scoping issues? > > Thanks! > ...scott > >
