Purely from performance perspective.
Goal: Ensure VM's memory allocation is guaranteed with lowest latency. VM running critical workload.
Option 1:
Ensure cluster memory resources are not overcommitted even during N+2 outage and take into VM memory overhead capacity buffer. This will ensure memory reclamation techniques are not triggered even during outages and the VMs get their allocated memory with lowest latency
Option 2:
Configure Memory reservation equivalent of VM size. This is guaranteed to work.
Thinking out loud on option 1. Are there any other scenarios where this VM will have to wait for the ESXi scheduler to reclaim memory pages prior allocating them to the VM?