CPU,RAM spec details for Elasticsearch Master & Data nodes

[purushothamkdr143 (Purushotham Reddy)]

Hi All,

I am setting up elasticsearch cluster on k8s using eck operator. From the document I understood that Heapsize should be no more than 50% of Allocated RAM so passed the details accordingly.

Details:

k8 cluster: 3 nodes(4CPU,60GB RAM) - total 16cpu 180gb ram
master nodes: 3(each - 8GB RAM, 4GB Heapsize)
data nodes: 3(each - 16GB RAM, 8GB Heapsize)

I am doing Loadtest on ES so I have below queries.

1. Do we need to provide RAM same for both master/data nodes in my case I have provided more RAM to data nodes alone? is this correct?
2. should I provide more cpu to datanodes or same for both master & data nodes?

[warkolm (Mark Walkom)]

All nodes in Elasticsearch need heap+system memory and CPU. However to your point, master and coordinating only nodes usually don't need as much as they won't store data.