Question: KVM vs. OpenVZ? Which should I choose?
Answer: This isn’t a technical breakdown of which one to choose but the basic breakdown. When it comes to OpenVZ versus KVM the decision can depend upon what you plan to do.
Choose OpenVZ if you are on a low budget. When comparing VPS plans by different web hosts you will notice that OpenVZ plans are a lot cheaper than KVM plans. Most web hosts that offer OpenVZ can oversell the resources on the host machine with OpenVZ. If your planned usage of the VPS doesn’t call for a custom kernel (OpenVZ does not support) or a lot of intensive resource usage than you can choose OpenVZ.
If you are not on a really tight budge than OpenVZ may not be what you want. KVM is typically a little most pricier compared to OpenVZ VPS plans. KVM enables you to install non-Linux OSes and have a custom kernel. while OpenVZ uses the host machine’s kernel. KVM is also better at isolating the different VPSes meaning your usage of the memory and CPU won’t knock your neighbor offline.
Bottomline: Choose KVM if you can. OpenVZ maybe cheaper but there are limitations to what the virtualization software can support (uses a shared kernel).