This might come in handy for admins using vCenter 6.
vCenter 6 now has dynamically adjusting heap size. It essentially looks at how much RAM you have allocated to your vCenter system and then allocates RAM accordingly to pretty much use up all available RAM for the java processes. Great for large environments as when you increase the RAM in your vCenter OS, it will sense that on reboot and assign more RAM to processes. What I don't like about it is in an environment where there's only 2 or 3 hosts (lab or small company) it uses all of the 8 GB of RAM allocated to vCenter regardless as to whether or not it's needed. This can be wasteful in a small environment with limited resources on the host.
After some poking around I found out there is a command to set custom sizes for the dynamic tool. Let me preface this by saying I highly doubt it's supported and would suggest it's a bad idea to do this in a production environment without VMware telling you to but, for lab purposes, it could come in handy.
Change to the following directory in order to run the command: c:\Program Files\VMware\vCenter Server\visl-integration\usr\sbin (or whatever the path is on your system)
cloudvm-ram-size -l
will list memory size to be allocated to processes
cloudvm-ram-size -S
will list current memory allocated to processes
What it doesn't tell you is how to customize the setting (likely because VMware doesn't want you screwing with it)
cloudvm-ram-size -C ### {processname}
will set a customMB size for the particular service.
This is reflected in the following file: c:\ProgramData\VMware\vCenterServer\cfg\service-layout.mfx. The customMB column will be populated with the custom settings and used on boot. I've noticed that I had to use the ciswin_name for the process on my Windows system when running the cloudvm-ram-size -C command.
