Your question - "if the VM with the reservation increases its demand, will the resources be "given back" to the VM instant, or will there be a tiny delay in access to the resources?"
Answer - "As long as the VM is "right-sized", it will get all the resources it demands."
Your question - "If I compare the 2 scenarios, will the response time for access to CPU resources be the same, or will Scenario 1 perform better?"
Answer - "It depends. If you are happy to manage the resources of the Stand-Alone Host yourself, then that is the safest option. The whole point of DRS is to make use of all the resources of the Hosts so that there is no wastage and reduces the TCO and increases ROI. At the end of the day, capacity management procedures must be in place to make sure you are not reaching saturation and resource contention.VCP6-DCV, VCP5, CCNA, MCTS 2008R2, MCSA 2008R2, CCA, ITIL.
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