Like you, I was seeing occasional problems of slow startup of the jvm, which is why I added that alternative source of randomness some years ago. It cured the problem. To be honest I have not followed up how relevant it still is today, but it doesnt seem tio do any harm :-). What has been your experience?
Sorry I had mised that earlier post regarding the memory problems. It sound like his postgres was probably over allocating memory.
To be honest I have not reviewed JAVA_OPTs as used in dhis2 server tools for some time, but rather left well alone. We will review this week.