[YeGoblynQueenne]

It's possible Ms Belotti and her team didn't realise they were working with an emulator. Mainframes being what they are, the programmers were probably never in the same room as the machines they were progamming, and it does take a bit of digging to figure out that the architecture you see before your eyes is emulated on another machine (like in "The Story of Mel").

Still, even the blog post you link to doesn't make it absolutely clear that java was running on an emulated s/370. It says that the decision was made to emulate the older architecutre rather than rewrite the old programs, but then it goes on to say "These are still operational". Does it mean the old programs? Or the old machines? It's hard to say.

As to how unlikely it is to see a very old machine still in use, instead of one made in more recent times, last year I talked to an engineer who claimed he had seen a PDP still in operation in some transport company if memory serves.

[abakker]

I believe (a coworker of mine worked on S/360) that all the old software can be effectively run through emulators on the current system z. The feeling was that once you had done the development and testing of an older system, IBM was never going to force you to rewrite your code. As a result, the upgrades were pretty seamless over the years. Many of those customers never had to upgrade and never had a reason to.

[vidarh]

PDP-10 was discontinued in 1983, but PDP-11 wasn't discontinued until 1997, with third-parties continuing to sell parts, so it's really not that unlikely to come across PDPs, depending on which line.