We’re currently facing some performance issues with our application and Couchbase is the culprit. One area we are looking at is the shear number of connections our application servers have with the couchbase cluster. My understanding is that each PHP-FPM process will create n+1 connections to the couchbase cluster where n is the number of nodes in the cluster. Since our application servers are configured to create 600 PHP-FPM processes that amounts to approximately 8000 connections for our 13 node cluster. Thankfully, in production, we only see it reach around 6000 connections.
How are others addressing this issue? We do have persistent connections turned on.