Real Mode

The hypervisor attempts to support real mode in a fully transparent manner. There might be situations, however, where specific processor implementations might not make this entirely possible. As a result, the hypervisor might be required to emulate or manipulate the environment to some degree to provide real-mode support. The following is a list of potential areas where real-mode support might not be transparent.

Hypervisor overhead inconsistencies

As a consequence of an increase in the frequency of instruction emulation by the hypervisor, performance of both the guest and the computer might be affected.

Visible processor state changes as a consequence of switching modes

The hypervisor might be required to make changes to the guest's run-time environment when mode switches occur, such as between real and protected mode or vice versa. Such changes might be detected by the guest.

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Build date: 11/16/2013