No, it's. VirtIO's balooning device can "inflate" to pseudo-allocate memory on a VM to free physical memory for other hosts.
Moreover, even if your files in memory, you cannot reserve "memory controller bandwidth". A VM using tons of memory bandwidth or a couple of cores in the same NUMA node with your VM will inevitably cause some traffic and slow you down.
Moreover, even if your files in memory, you cannot reserve "memory controller bandwidth". A VM using tons of memory bandwidth or a couple of cores in the same NUMA node with your VM will inevitably cause some traffic and slow you down.