AWS Elasticache high performance setup

For one of our PImcore installations we have identified the performance of the datacache backend Redis as the bottleneck. We use autoscaling and are using AWS Elasticache as a common cachebackend for all nodes.

If we try to set the cluster size to one (1) node and use a local Redis server we see higher performance in our application.

How could we setup Elasticache with high performance to atleast achieve the same performance as for a local installed Redis?

Here is a comparsion between a local Redis server and the Elasticache Redis 4.0.10 node

ubuntu@ip-172-31-42-238:~$ redis-benchmark -r 1000000 -n 2000000 -t get,set -q -h localhost

SET: 99304.87 requests per second

GET: 99835.27 requests per second

ubuntu@ip-172-31-42-238:~$ redis-benchmark -r 1000000 -n 2000000 -t get,set -q -h test10.zbwdbu.0001.euw1.cache.amazonaws.com

SET: 66321.80 requests per second

GET: 67012.90 requests per second

The Elasticache instance type is cache.r5.xlarge