The traditional and typical search use case is the one large search collection distributed among many nodes and shared by all users. However, there is a class of applications which need a large number of small or medium collections which can be used, managed and scaled separately. This talk will cover our effort in helping a client set up a large scale SolrCloud setup with thousands of collections running on hundreds of nodes. I will describe the bottlenecks that we found in SolrCloud when running a large number of collections. I will also take you through the multiple features and optimizations that we contributed to Apache Solr to reduce or remove the choke points in the system. Finally, I will talk about the benchmarking process and the lessons learned from supporting such an installation in production.