Is there something wrong with the latest version?
I have about 3 hours coding and the amount or RAM that it is using is simple ridiculous almost 4GB and is a small to medium size project, just one.
Previously I was running the 2019.X version of RubyMine with 3-5 projects open at the same time and it had a similar resource consumption.
Build #RM-211.7442.41, built on June 1, 2021
Licensed to RubyMine Evaluator
Expiration date: July 11, 2021
Runtime version: 11.0.11+9-b1341.57 x86_64
VM: Dynamic Code Evolution 64-Bit Server VM by JetBrains s.r.o.
GC: G1 Young Generation, G1 Old Generation