Previously we saw tutorial about Dynamic Memory in Hyper-V. Today, we will see Smart Paging in Hyper-V. We strongly advise you to consult this tutorial before coming to it in order to better understand it.
We will now see what exactly Smart Paging is and its contribution in this explanatory tutorial.
For information Smart Paging is also called as “intelligent pagination”. It is a mechanism to counteract the difficulties that may be encountered during the restart of a machine, if the Hyper-V is not able to assign VM to its minimum RAM which required for starting a machine (Startup RAM).
This is due to the fact that due to the dynamic memory allocation, VMs have their memory threshold which varies from each other. Therefore, when you try to restart a VM and if there is not enough memory available and the Hyper-V host is also not able to recover minimum required RAM from the other VM, the VM cannot start. Fortunately, now we have Smart Paging feature.
Indeed, in this case a Smart paging file will be created and used to virtual machine time that Hyper-V host can allocate the minimum RAM which is necessary. Once the RAM allocation carried out, the Smart Paging file will be automatically deleted. Moreover, it will be stored at the location indicated in the VM’s properties.
To unload the VM memory allocated through Smart Paging, technology “Memory Ballooning” is used as in the case of DRAM via Windows Memory Manager. Note that Smart Paging is a temporary mechanism. This allows the virtual machine to start but this memory cannot be used indefinitely to the virtual machine.
Besides, Microsoft recommends not using this feature more than 10 minutes on a machine while specifying RAM – as we said – that this in only temporary.
The Smart Paging can be used for restarting a VM or while resetting the VM. And if there are no VMs or physical RAM available, then it is not possible to recover the RAM on the other VMs.