Dedicated server or virtual private server hosting?

Drupal informs me that my blog account is now 2 years and 22 weeks old. When I initially setup this website, I had the choice of going either with a dedicated server again or to try out a virtual private server. I opted with the later and I guess now would be a good time to take stock of hosting plans.

Cost

VPS is the hands down winner here. The only thing that could possibly be cheaper than a VPS would be shared hosting, but as I wrote in an earlier blogpost, shared hosting is just not an option if you want to use any content management system.

Reliability

Again, hands down winner is the VPS. No hardware means no hardware failure and given the average MTBF of fans and harddisks, I should have experienced at least one catastrophe by now. In fact, I am quite sure, that the underlying hardware of the onyxbits.de server has already broken down at least once, without me noticing a thing.
I still woefully remember the trouble, I once had with a broken fan in a cluster of identical machines. By the time that thing decided to go bust, the manufacturer was no longer selling that exact product line, making it difficult to acquire spare parts. Virtual hardware can really be a bliss.

Another neat thing about virtual private servers is that their hosting plan usually includes an automatic and hassle free backup service. From your hosting company's point of view, your entire harddisk is just a file, sitting on their file server, so mirroring your entire filesystem to the backup server is pretty trivial.

Security

Here, dedicated servers trump. If anything about your site screams HTTPS, than dedicated hosting is the way to go. When you cannot trust your telecommunication carrier with your data, than you also cannot trust your hosting provider with your servers. When privacy is a concern, your machines just need intrusion detection and you must most certainly not allow an external backup service to simply mirror your filesystem.

Besides no control over the hardware, virtual private servers also have two additional disadvantages:

• You have to rely on your hosting provider to take system security serious. That is, you have to trust the hypervisor to properly protect your compartment from attacks of other customers on the same physical machine.
• Your choice of operation systems is limited, since the hypervisor usually demands custom kernels in order not pay the performance penalty for full hardware emulation.

The second point is especially alarming as it does not allow you to patch operation system bugs yourself.

Performance

Here, I'd call a tie between dedicated servers and VPS. Real hardware is, of course, always more powerful than emulated hardware. However, this does not matter at all unless you intend to go to the limits of what silicone has to offer. In reality, you should know how much computing power you need and be able to order an appropriately sized server with enough reserve.
Virtual servers do have the advantage of being easier to upgrade when more performance is need. They have the disadvantage of load spikes of other customers negatively affecting you.