Today, I’ll talk about a thing that any sysadmin running Hyper-V VMs does (or still dreams about) while managing infrastructure resources: hot modifying assigned to VM memory amount. I’ll discuss not only the feature itself but also how it works on different OS and its impact on the environment stability.

All of us keep an eye on resource consumption within our environments. If a VM needs extra RAM to have the job done, we provide it with some, right? And, we usually run many VMs on our servers each with own purpose and configuration. That’s, actually, why changing the amount of assigned to a VM memory without rebooting it may come in handy. Also, many guys run some parts of their environments on Windows while having other parts run on something from Linux family. Looks pretty hectic in terms of management, doesn’t it?