- ElasticSearch is not sending too much data over the network
- But ElasticSearch is leveraging http(s) protocol, http2 seems to be still work-in-process
- Number of sockets opened on the server, on the client, and on the network appliance could be a problem
- Server was alright since it listens on one port, the client running heavy batch job was not, it was getting saturated with the response sockets