When a web site or hosted application out grown the shared hosting accounts, the natural progression is usually stepping up to a VPS or a dedicated server. I have seen quite a few times on WHT where people ask whether they should go to dedicated or virtual private server — usually those with budget slightly more than a good shared hosting, and looking for places to run their busy websites. Surprisingly I have seen a lot of people putting their preference on cheap dedicated servers.

I will go for a VPS, if I have limited budget, and have a busy site to host.

For example, you happen to have $70/month to get something semi-decent. On one hand, you have a cheap dedicated server from a ServerPronto (one of the cheapest dedicated server providers), on the other hand, you have a top-level Xen setup on SliceHost.

  ServerPronto – AMD Power SliceHost – 1024slice
CPU AMD 2600+ 2x Opteron 265
Memory 512Mb 1024Mb
Storage 80Gb 40Gb
Transfer 400Gb 160Gb
Cost $69.95/mo + $69 setup $70/mo

They look “somehow” comparable, aren’t they? SliceHost has slightly better CPU power — remember their physical box has quad core but they are shared with 4-7 other 1024slices on those 8Gb Opteron boxes, plus very minimal overhead on Xen. Twice the memory will be very helpful to keep your Apache processes from swapping in and out of disks. Storage and transfer are lacking, but (1) they are soft-limit on SliceHost, and (2) they don’t oversell bandwidth.

Note that I have no experience with ServerPronto. I did have some recent experience with SliceHost. However if I do have a budget of $70/mo I would be giving ServerAxis a try, who is actually cheaper with their better-equipped VPSs.

Alright — so they are on-par on paper. But let me show you why getting a VPS is much better.

  • CPU is burstable. When all the virtual servers are fighting for CPU, you might feel like running on the same speed as a AMD 2600+. However, when there are idle cycles, you are free to grab them. So the end result can be much faster than that 3-year-old chip in that cheap dedicated, sometimes.

  • I/O is burstable. Slow disk IO is usually the most criticised short-coming of VPS, but I noticed that it usually only happen on crowded Xen or oversold Virtuozzo servers. Well in SliceHost’s case, you don’t get a dedicated 40Gb hard disk for your slice, but on a shared RAID1 storage of much bigger and faster drives. End result? Much faster disk I/O when other VPS’s are not fighting for it. Many other VPS providers use RAID5, RAID10 or 0+1 on very fast SATA, SCSI or SAN volumes.

  • Redundant storage. Most VPS have RAID on their drives, because everyone knows — hard drives will die. After quite a few incidents at home, I will not trust my data on anything that is not RAIDed. Not only do they provide redundancy, but also faster recovery if one of the drives does die, to minimise down time.

  • Server grade hardware. What do you think your AMD 2600+ box is? A well designed rack unit with redundant power supply and sufficient cooling? Server grade motherboard with ECC memory? Most likely a beige desktop box. Whereas other dual Xeon/Opteron boxes used to host VPSs are definitely better designed and equipped.

  • Extra management. Both VPS and dedicated servers are “unmanaged”, but I’ll argue that VPS are more managed than a dedicated server. The host’s administrator will look out for hardware issues. They’ll help you to make sure your VPS boots. Some of them even provide virtual console so you can diagnose issues yourself. Remote console, reboot support, etc can all cost extra on dedicated servers.

  • Better for the environment. Not sure whether you care, but you can squeeze in more VPS into the same rack than cheap dedicated servers. Thus less electricity is used. Somehow it is better for the environment, making your providers less depending on the more and more expensive energy price.

Well. I am sure there are more reasons, but all these should have concluded that there’s few reason to get “cheap dedicated” these days. Moreover, the real sweet spot of VPS is less than $50/month, which is enough to get a medium-level VPS to host multiple website or a “single purpose” web application. What kind of dedicated do you expect to get with that amount of money?

Hosts can also take advantage of virtualization. Besides “better for environment”, better CPU utilization, VPS also has advantage of faster provisioning. Most dedicated servers take a few hours to provision a new server request, and longer if hardware is not available. Most VPS provisioning can be scripted and automated, provided there’s enough room on the host node.

Yes, dedicated servers do get more consistent performance. More consistent CPU response. More consistent IO throughput. But, choosing between being consistent with a AMD 2600+ performance, or burstable to dual Opteron 265 performance — I think I know which one I’ll go.