You can now hibernate your VMs to save compute costs. When you hibernate a VM, Azure persists the VM’s in-memory state in the OS disk and deallocates the VM. As a result, you don’t have to pay for the VM when its hibernated and you only pay for any storage and networking resources associated with the VM. When you later start the VM, the applications and processes that were previously running resume from their previous state, allowing you to quickly pick up from where you left off.
Learn more about VM hibernation in the documentation and the blog.