Since upgrading to Elasticsearch 7.4.1 from 2.4. (I know ) we are seeing our AWS availability zone transfer charges skyrocket. Both the old and new clusters used the
cluster.cloud.allocation.awareness.attributes: aws_availability_zone setting and are deployed across 3 AZ's within an AWS region.
What I'm wondering is, did we miss some "compress internal communication" setting or similar for shard shuffling?
Does ES7 move more shards than 2.4? We have
cluster.routing.allocation.node_concurrent_recoveries: set to 2 for both, but didn't notice much difference if we went to 8.
Found this https://www.theguardian.com/info/2020/feb/04/taming-data-transfer-costs-with-elasticsearch but they seemed to be having problems with queries costing more.
Our costs are directly linked to the data nodes and appears to be them talking to each other.