6.7

Table Of Contents
1GB page vRAM backing is opportunistic and 1GB pages are allocated on a best effort basis. This
includes cases where host CPUs do not have 1GB capabilities. To maximize the chances of having guest
vRAM backed with 1GB pages, we recommended to start VMs requiring 1GB pages on a freshly booted
host because over time the host RAM is fragmented.
A VM with 1GB pages enabled can be migrated to a different host. However, the 1GB page size might not
be allocated on the destination host in the same amount as it was on the source host. You might also see
part of vRAM backed with a 1GB page on the source host is no longer backed with a 1GB page on the
destination host.
The opportunistic nature of 1GB pages extends to vSphere services such as HA and DRS that might not
preserve 1GB page vRAM backing. These services are not aware of 1GB capabilities of destination host
and do not take 1GB memory backing into account while making placement decisions.
vSphere Resource Management
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