What do Virtual Private Server vs Dedicated Cloud run on?
Solution 1:
If we are talking about hosting companies selling only Linux VPS, then in most cases they use OpenVZ/Virtuozzo for virtualization, which is not providing virtual machines but virtual containers, inside your VPS you won't have access to kernel options, as it shares kernel with host, and is more vulnerable to disruptions from other containers.
VPS can also be a standalone Xen/VMware/Hyper-V/KVM host if they are also selling Windows and not just Linux VPS, and depending on host company they can be using just one virtualization software, and they could be using multiple different ones.
Cloud VPS, or Dedicated Cloud, will usually be VMware or Xen hypervisors joined in a cluster, and connected to a shared storage, sharing connections to same SAN.
Difference between VPS, and Cloud machine is usually that VPS is a container/VM running on a single host, where host is both a hypervisor, and storage. Cloud machine will run on several hypervisors, which are all connected to a same storage, and VM can be moved between hypervisors for better load balancing, and less downtime in case or hardware issue, and maintenance.
Both VPS, and Cloud machines can have issues with running on hypervisors that are overselled, and where total number of resources assigned to all VMs is bigger then the actual resource pool.
Each hosting company can have its own definition of what they call VPS, and what they call Cloud machine.
If your current VPS is linux machine, you can check if it is OpenVZ/Virtuozzo or some other virtualization software by installing virt-what package, which is in most stanard repos, and running virt-what command in shell.
https://linux.die.net/man/1/virt-what
Solution 2:
The statement that VMware gives you perfect isolation is not true at all. KVM does a better job, however isolation is about resources not about the hypervisor they use.
If you share the same physical disk between two VMs that hosts disk intensive applications you will have performance problems. If you share the same memory bank between two VMs you will have contention. If you share the same network adapter you will have contention.
The difference between good and bad providers is more like that. Not which virtualization software they use.
It is like then difference from a hostel to an apartment building. The first several rooms share the bathroom and the kitchen. The second every room has their own.
Solution 3:
What do Virtual Private Server vs Dedicated Cloud run on?
How long is a piece of string?
:)
Honestly, though, both of those terms are marketing terms that are not easily definable. To get a true understanding of what a provider means when they use either of those terms, one needs to dig into the technical details. The view you're getting from your hosting provider is their own view into things, which does not in any meaningful way translate to other providers.
In a very broad swath, here's how I'd define them, based off of my experience with many different providers:
VPS: a virtual machine, (usually) running on shared hardware, that you have full administrative access to.
Dedicated Cloud: a set of physical hosts, dedicated for a single customer's use, installed and configured with some type of virtualization platform, be it Hyper-V, ESXi, KVM, Xen, Openstack, etc.
Beyond the above (admittedly broad) definitions, do not make any assumptions about what functionality any solution provides or does not provided based on the marketing name of the product alone. You must dig into the actual technical details in order to gain an understanding, and for some things even that isn't enough - you may need to actually gain real hands-on experience with a product to be able to truly evaluate it.
I must emphasize this - do not place any weight on what your hosting provider recommends. They have their own agenda, which doesn't necessarily align with your best interests. If you are not confident digging into this on your own, I'd very much suggest that you hire someone for a short contract. This person can help you identify your requirements and then in a truly vendor-agnostic way, converge on a vendor and solution that best satisfies your requirements.