KVM and OpenVZ are two virtualization technologies used by VPS providers. KVM provides full virtualization: each VPS gets its own kernel and a fixed amount of RAM. OpenVZ uses container-based virtualization on a shared host kernel, with RAM that is often burstable.
Quick Comparison
| Feature | KVM | OpenVZ |
|---|---|---|
| Virtualization type | Full (hardware-level) | Container (OS-level) |
| Reserved RAM | Yes | Shared/burstable |
| Custom kernel | Yes | No (shared host kernel) |
| Docker support | Yes | Limited/none |
| OS options | Any (Linux, Windows, BSD) | Linux only |
| Performance ceiling | Higher | Lower |
| Price | Slightly higher | Usually cheaper |
| Isolation | Full | Partial |
| Swap | Configurable | Usually disabled |
Why KVM Is Better for Game Servers
Reserved RAM
KVM gives your VPS its own block of RAM, so other users on the host cannot take your memory. On most KVM plans, Space-Node's included, the vCores are still shared with the other VPSes on the host, so ask a provider how it shares CPU before you put a busy Minecraft or FiveM server on it.
OpenVZ shares resources between containers. During peak hours, you may experience performance drops because other users consume shared CPU or RAM.
Docker Support
KVM supports Docker natively. You can run Pterodactyl, containers, and any Linux software. OpenVZ has limited or no Docker support.
Custom Kernel
KVM lets you use your own kernel. This matters for:
- Running specific Java versions optimized for Minecraft
- Using custom TCP settings for game traffic
- Loading kernel modules for WireGuard or other VPN software
When OpenVZ Is Acceptable
- Simple websites and blogs
- Small Discord bots
- Development and testing
- Budget-limited projects where consistent performance is not critical
FAQ
Is KVM or OpenVZ better? KVM is better for virtually all use cases. It provides reserved RAM, Docker support, and full OS access.
Why is OpenVZ cheaper? Providers can pack more OpenVZ containers on one host because resources are shared.
Does Space-Node use KVM? Yes. All Space-Node VPS plans use KVM virtualization. The RAM is dedicated to your VPS and the vCores are shared with the other VPSes on the node. Premium VPS plans (Ryzen 9 9950X) can be ordered from €4.20 a month and Standard VPS plans (AMD EPYC 7452) from €4.99 a month.
Can I run Docker on OpenVZ? Usually not. OpenVZ does not support the kernel features Docker requires.
Related: Best VPS Netherlands, Pterodactyl VPS setup, VPS vs Dedicated