Specifications

Best Practices for Virtualizing and Managing Exchange 2013
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Figure 28: Hyper-V Smart Paging
Hyper-V Smart Paging can lead to some performance degradation due to slower disk access speeds.
Therefore, to ensure that the performance impact of Smart Paging is minimized, this feature is used only
when all of the following are true:
 The virtual machine is being restarted.
 No physical memory is available.
 No memory can be reclaimed from other virtual machines that are running on the host.
Memory ballooning: Memory ballooning is a technique used to further reduce the performance impact
of Hyper-V Smart Paging. Once the virtual machine is restarted and the need for memory is less than the
startup memory, Hyper-V can stop using Smart Paging. Therefore, Hyper-V removes the temporary
memory from the virtual machine by coordinating with Dynamic Memory components inside the guest (a
process sometimes referred to as ballooning). With this technique, use of Hyper-V Smart Paging is
temporary and is not expected to be longer than 10 minutes. Figure 29 shows Hyper-V removing memory
from the virtual machine after it completes the startup process.
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Figure 29: Removing paged memory after virtual machine restart