I had this question after viewing VMWare Resource Limiting
Disclaimer: I am a senior DBA, new to VMware (and several other SA responsibilities). What I've studied so far isn't focused enough on my immediate need.
I've inherited a single server, ESXi 5.10, with several guest VMs. Each guest runs Oracle systems on RHEL. All but one of the VMs are production. I'm tasked with converting the one non-production VM into a scratch/ lab platform. This repurposed VM, which I'll call LAB1, will be staged with current versions of RHEL and Oracle,
To illustrate, say that I have three prod VMs plus LAB1. The resource distribution seen in vClient is 30-30-30-10. My target is 25-25-25-25. As far as I can tell, prod CPU usage is very low, and memory use is mostly low to moderate. I'm not aware of any resource pools, reserves, etc. It stands to reason that my alterations will come in gradual steps.
So, please help me keep from crashing production while I learn from my mistakes :) TIA.