Wrong Remaining RAM Value [EE 6.0.1 build 2037]?

I built a cluster in AWS with 4 data nodes, 8GB each (c5.xlarge instances) and 2 index/query nodes 32GB each (c5.4xlarge instances).  No buckets are defined.  The "remaining RAM" value is shown correctly for index/query nodes (80% of 32GB is ~25.7), but not for the data nodes (it shows 3.16GB) – see below.

The maximum data quota can be specified correctly at ~6.4GB (80% of 8GB):

I can assign the maximum quota (6445MB) to a single bucket, and the stats will then show correctly the amount of RAM available per node:

So, it's only the "remaining RAM" value on the charts in the node list that doesn't have the number.