ESXi 6.5 vNUMA Changes

If customers have VM’s configured with non-default Cores per Socket settings or have the advanced parameter “numa.autosize.once = False”, they should enabled the following:

“Numa.FollowCoresPerSocket = 1”

Reason:  Changes were made in ESXi 6.5’s vNUMA topology configuration to improve performance.

“With this new optimization, the virtual NUMA topology corresponds more to the actual physical NUMA topology, allowing the operating system to correctly optimize its processes for correct local and remote memory access.”

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