While I do not know the specifications of your Elasticsearch cluster, I am really surprised by your experience. We (at skroutz.gr) use a moderately small clust

While I do not know the specifications of your Elasticsearch cluster, I am really surprised by your experience. We (at skroutz.gr) use a moderately small cluster (four nodes) and easily process > 4 million rows a day and view them on Kibana dashboards in real-time. We also have success running aggregations on data going back as far as 3 months.