Why KVM is the Future of Virtualization: Escaping the OpenVZ Trap
Let’s be honest. If you are running a production database or a high-traffic e-commerce site on a budget VPS today, you have likely hit the "wall." Your load average spikes, but your traffic hasn't changed. Your disk I/O crawls, but your logs are quiet.
The culprit? You are probably stuck in an oversold OpenVZ container.
It is 2010. The days of sharing a single kernel with three hundred other users should be over. While OpenVZ has served the budget market well, serious systems administrators are migrating to Kernel-based Virtual Machine (KVM). At CoolVDS, we have bet the farm on KVM for our Norway node, and the benchmarks back us up. Here is why true hardware virtualization is the only path forward for professional hosting.
The Myth of "Dedicated" Resources
In container-based virtualization (like OpenVZ or Virtuozzo), you aren't running your own Operating System. You are running a userspace instance on top of the host's kernel. This is efficient for the host, but dangerous for you.
If another customer on the same physical server decides to run a fork bomb or a poorly optimized MySQL query, the shared kernel scheduler has to work overtime. You feel that lag. In the hosting industry, we call this the "Noisy Neighbor" effect.
KVM is different.
KVM leverages the Intel VT-x and AMD-V hardware extensions built into modern CPUs. When you provision a server with us, you get your own kernel. If your neighbor crashes their kernel, your uptime remains 100%. It is true isolation.
Technical Deep Dive: Tuning I/O for KVM
One of the biggest advantages of KVM in RHEL 5.4 or Ubuntu 9.10 is the ability to tune your I/O scheduler independent of the host node. In an OpenVZ container, you are stuck with whatever the host uses (usually CFQ).
With KVM, you can optimize for throughput. For a database server running on our high-speed SAS RAID arrays, we recommend switching to the `deadline` or `noop` scheduler inside your VM to reduce latency.
Here is how you do it in your grub configuration (`/boot/grub/menu.lst`):
kernel /vmlinuz-2.6.31-19-server root=/dev/mapper/root ro quiet splash elevator=noop
After a reboot, verify it:
$ cat /sys/block/vda/queue/scheduler
[noop] anticipatory deadline cfq
Pro Tip: If you are using VirtIO drivers (which you should be on CoolVDS), the `noop` scheduler often outperforms others because the hypervisor handles the disk sorting logic. This can drop I/O wait times by up to 20%.
Data Sovereignty in Norway
Beyond the raw specs, we need to talk about compliance. The Norwegian Personal Data Act (Personopplysningsloven) of 2000 is strict. With the growing concern over data privacy in the US and the complexities of the Safe Harbor framework, knowing exactly where your data sits is critical.
Latency matters too. If your primary customer base is in Oslo, Bergen, or Trondheim, hosting in Germany or the US adds unnecessary milliseconds to every handshake.
| Feature | OpenVZ / Containers | CoolVDS KVM |
|---|---|---|
| Kernel | Shared (Host Kernel) | Dedicated (Customizable) |
| Swap Space | Fake (Burst RAM) | Real Partition |
| Isolation | Software Level | Hardware Level (Intel VT) |
| IPTables/Tun | Requires Host Activation | Full Control |
The CoolVDS Approach
We do not believe in overselling. When you buy 1GB of RAM on our platform, that memory is reserved for your KVM instance. We utilize RAID-10 15k RPM SAS drives (and are currently testing early enterprise SSDs) to ensure that disk I/O is never the bottleneck.
For systems administrators who need to run custom modules, compile their own kernels, or set up complex VPN tunnels, KVM is the only logical choice. You get the power of a dedicated server with the flexibility of virtualization.
Stop fighting for resources you already paid for. Experience the stability of hardware-backed virtualization connected directly to the NIX (Norwegian Internet Exchange).
Ready to upgrade your infrastructure? Deploy a pure KVM instance on CoolVDS today and feel the difference low latency and true isolation make.