Comment by rbanffy

Not to be nasty, but we used to call them mainframes. A mainframe is still a perfectly good solution if you need five nines of uptime, with transparent failover of pretty much every part of the machine, the absolute fastest single-thread performance and the most transaction throughput per million dollars in the market.

I would not advise anyone to run them as a single machine, however, but to have it partitioned into smaller slices (they call them LPARs) and host lots of VMs in there (you can oversubscribe like crazy on those machines).

Managing a single box is cheaper, even if you have a thousand little goldfish servers in there (remember: cattle, not pets) and this is something the article only touches lightly.