Dynamic Resource Scheduling (DRS) should be enabled for all VMware host clusters, especially those who run SQL Server. It provides for resource consumption load balancing functionality into a host cluster. Consider enabling the DRS load balance based on consumed memory rather than active memory (available as of vSphere 6.7), as the active memory counter for SQL Server-based VMs is not a true representation of memory usage by the SQL Server layer.
The CPU over-commitment metric could be used to control a vCPU overcommitment ratio, but we prefer to leverage the vCPU Ready overhead metrics to better gauge, as the CPU overcommitment by core ratio never factors in the actual consumption rates of the individual virtual machines themselves. Certain SQL Server workloads could be so busy that CPU overcommitment could be ruled out completely, and others could be so underutilized that a ratio of over six to one could exist with no significant performance penalties.
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