Hi Shushuai, Just a few thoughts.
I would guess that most people would argue for implementing multi-tenancy within your core (via some unique filter ID) or collection (via document routing) because of the headache of managing individual cores at the scale you are talking about.
There are disadvantages the other way too: having a core/collection support multiple tenants does affect scoring, since TF-IDF is calculated across the index, and can open up security implications that you have to address (i.e. making sure a malicious query cannot get another tenants documents).
The most important thing you have to lock down is whether there is a need to customize the schema/solrconfig for each tenant. If there is, then having individual cores per tenant is going to be a stronger argument. If I was to guess, and based on my own multi-tenant experience, you'll have some high-end tenants who need their own cores/collections, and a larger number that can all share a configuration. Its like any kind of hosted solution: the cheapest version is one-size-fits-all and involves the minimum of management overhead, while the higher end are more expensive and require more management.
My own preference is for a blended environment. While the management of individual cores/collections is not to be taken lightly, I've done it in a variety of hosting situations and it all comes down to smart management and the intelligent use of administrative scripts. I've developed my own set of tools over the years and they work quite well.
Finally, I would (in general) argue for cloud-based implementations to give you data redundancy, but that decision would require more information.
HTH, Lajos Moczar theconsultantcto.com Enterprise Lucene/Solr On 14/03/2014 23:10, shushuai zhu wrote:
Hi, I am looking into Solr 4.7 for best practice of multi-tenancy support. Our use cases require support of thousands of tenants (say 10,000) and the incoming data rate could be more than 10k documents per second. I did some research and found people talked about scaling tenants at all four levels: Solr Cloud Collection Shard Core I am listing them plus some quoted comments from the links. 1) Solr Cloud and Collection http://find.searchhub.org/document/c7caa34d807a8a1b#c7caa34d807a8a1b ----------- Are you trying to do "multi-tenant"? If so, you should be talking "multi-cluster" where you externally manage your "tenants", assigning them to clusters, but keeping tenants per cluster down in the dozens/hundreds, and "archiving" inactive tenants and spinning up (and down) clusters as inactive tenants become active or fall into inactivity. But keeping 1,000 or more tenants active in a single cluster as separate collections is... a no-go. ----------- 2) Shard http://searchhub.org/2013/06/13/solr-cloud-document-routing/ ----------- Document routing can be used to achieve a more efficient multi-tenant environment. This can be done by making the tenant id the shard key, which would group all documents from the same tenant on the same shard. ----------- 3) Core http://find.searchhub.org/document/4312991db2dd90e9#4312991db2dd90e9 ----------- Every multitenant situation is going to be different, but at the extreme a single core per tenant is the cleanest and provides the best separation, optimal performance, and supports full tf-idf relevancy of document fields for each tenant. ----------- http://find.searchhub.org/document/fc5b734fba135e83#fc5b734fba135e83 ----------- Well, we try to use Solr to run a multi-tenant index/search service. We assigns each client a different core with their own config and schema. It would be good for us if we can just let the customer to be able to create cores with their own schema and config. ----------- I also saw slides talking about scaling time along Collection: timed collections (slides 50 ~ 58) http://www.slideshare.net/sematext/solr-for-indexing-and-searching-logs According to these, I am thinking about the following approach: In a single Solr Cloud, the multi-tenant support is at Core level (one or more cores per tenant), and for better performance, will create a collection every day. When a tenant grows too big, will migrate it from this Solr cloud to a new Solr Cloud. Any potential issue with this approach? Is there better approach based on your experience? A few questions related to proposed approach: 1) When a core is replicated to multiple nodes via multiple shards, the query submitted against a particular core (tenant) should be executed distributed, right? 2) What is the best way to move a core from one Solr Cloud to another? 3) If we create one collection per day and want to keep data for three years for example, is it OK to have so many collections? If yes, is it cheap to maintain the collection alias for easy querying? Thanks. Shushuai
