Elastic Cloud Enterprise scales to whatever capacity you need, pure and simple. If you need more processing capacity because your allocators are close to being to maxed out, install Elastic Cloud Enterprise on additional hosts and assign the allocator role. The constructor immediately recognizes and provisions these additional resources so that they can start processing user requests.
ECE version 1.0.x takes a fill first approach to using up all available space on previously used allocators before starting to use new ones. A future version of ECE will offer a distribute first approach that ensures the distribution of Elasticsearch clusters across available allocators, including any new ones that you might have added recently.
Proxies redirecting user requests need to scale based on the ingest and search demands on Elasticsearch or Kibana instances. The load on proxies also depends on the algorithm specified by your load balancer. If you find that CPU and memory on your existing proxies are being maxed out regularly, it is time to add another proxy.
Coordinators and directors scale based on the overall load on the infrastructure of the Elastic Cloud Enterprise installation. In production environments, we recommend that you always use at least three directors and coordinators, preferably separating these roles by placing them on separate runners. Even a large-scale deployment will most likely not need to scale to a number that exceeds five.
To learn more, see adding capacity.