Problem:
We have a XenServer 7.2 environment running Windows Server 2019 terminal servers. Although seemingly random, we see the VM climb to a whopping 32GB of used memory and the users slow to a crawl until we reboot the guest OS.
When running RAMmap I can see that nearly all the memory is stuck in "Driver Locked" and is never being released. It just climbs and climbs until users complain of slowness and then we have to reboot the guest OS.
What causes Driver Locked Memory to not be released and continue to "leak"? Again, we are running XenServer 7.2 with Windows Server 2019. All Windows updates have been applied to the guest OS.
We have plenty of resources across 8 XenServer host servers and 2 grouped SANs for storage.
The startup and maximum memory on the VM is set to the same value of 32GB and "Automatically allocate memory within this range" is not checked.