What Happens When You Mix Java with a 1960 IBM Mainframe • Hacker News Board

Re: What Happens When You Mix Java with a 1960 IBM Mainframe

#11

Post by geodel » Mon, Jan 23, 2017, 8:24 PM UTC

I have heard from many of my friends about massive projects of 'modernizing' mainframe applications with Java stack. Java did not deliver improvement that management was expecting. Once the project consumed all the budget for ~25% completion, they were scrapped.

I think, though without any proof, that overreliance of 100s of mixed quality libraries, combined with 'best practices' of enterprise development and heavy application of design patterns creates a very large surface area for change. This makes reasonable translation of functionality to Java almost impossible.

Re: What Happens When You Mix Java with a 1960 IBM Mainframe

#12

Post by cle » Mon, Jan 23, 2017, 8:30 PM UTC

skissane wrote: post #4

Is someone in the US government really still using an IBM 7074? Really? I'm shocked. How could that possibly be cost-effective? Actually, this blog post makes the story clearer: http://nikhilism.com/post/2016/systems-we-love/ It isn't a physical IBM 7074. When it came time to migrate from 7074 to S/360, rather than rewriting their 7074 software, they just wrote a 7074 emulator for S/360. And, it sounds like, they are…

It's "cost effective" because "cost effectiveness" is not as objective as we think, once we start considering things like risk tolerance.

Re: What Happens When You Mix Java with a 1960 IBM Mainframe

#13

Post by walrus01 » Mon, Jan 23, 2017, 8:33 PM UTC

When I first saw the Chromebook, my thought was that Larry Ellison's 1998 dream of a network computer thin terminal had come true. It's smarter than a true thin terminal, but everything lives in the cloud (err, butt).

Re: What Happens When You Mix Java with a 1960 IBM Mainframe

#14

Post by YeGoblynQueenne » Mon, Jan 23, 2017, 8:37 PM UTC

>> It was at this point that the seasoned data architects in the department began expressing their exasperation. “15 years ago, everybody was telling us ‘Get off the mainframe, get on AT&T applications, build these thick clients. Mainframes are out.’ And now thick clients are out, and everybody’s moving to APIs and microservices, which basically are very similar to the thin client that a terminal uses to interact with a mainframe.”

A.k.a. "Them as not knows their history are doomed to repeat it". But I suppose it's more the case of business imperatives than real ignorance that drive this mad race to make new stuff that works worse than the old stuff only so we can then go back to the old stuff with a different name.

Btw, that lady is my new tech hero:

“The systems that I love are really the systems that other engineers hate,” Bellotti told the audience — “the messy, archaic, half chewing gum and duct tape systems that are sort of patched together.

<3 <3 <3

Re: What Happens When You Mix Java with a 1960 IBM Mainframe

#15

Post by mbellotti » Mon, Jan 23, 2017, 8:42 PM UTC

skissane wrote: post #4

Is someone in the US government really still using an IBM 7074? Really? I'm shocked. How could that possibly be cost-effective? Actually, this blog post makes the story clearer: http://nikhilism.com/post/2016/systems-we-love/ It isn't a physical IBM 7074. When it came time to migrate from 7074 to S/360, rather than rewriting their 7074 software, they just wrote a 7074 emulator for S/360. And, it sounds like, they are…

> A lot of legacy, sure, but I think this article makes it sound even more legacy than it really is.

Indeed. The point of the talk was that 1) legacy is often assumed to be bad not for any real technical reasons but just because it is legacy and 2) a lot of what was being presented as legacy wasn't even legacy. Their OS 2200 version was actually newer than the Oracle DB they were using on the "modern" side of the stack.

Re: What Happens When You Mix Java with a 1960 IBM Mainframe

#16

Post by neeleshs » Mon, Jan 23, 2017, 8:51 PM UTC

geodel wrote: post #11

I have heard from many of my friends about massive projects of 'modernizing' mainframe applications with Java stack. Java did not deliver improvement that management was expecting. Once the project consumed all the budget for ~25% completion, they were scrapped. I think, though without any proof, that overreliance of 100s of mixed quality libraries, combined with 'best practices' of enterprise development and heavy a…

Was it Java that did not deliver improvement, or was it the team? :)

Re: What Happens When You Mix Java with a 1960 IBM Mainframe

#17

Post by YeGoblynQueenne » Mon, Jan 23, 2017, 8:55 PM UTC

skissane wrote: post #4

Is someone in the US government really still using an IBM 7074? Really? I'm shocked. How could that possibly be cost-effective? Actually, this blog post makes the story clearer: http://nikhilism.com/post/2016/systems-we-love/ It isn't a physical IBM 7074. When it came time to migrate from 7074 to S/360, rather than rewriting their 7074 software, they just wrote a 7074 emulator for S/360. And, it sounds like, they are…

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.

Re: What Happens When You Mix Java with a 1960 IBM Mainframe

#18

Post by mbellotti » Mon, Jan 23, 2017, 8:58 PM UTC

This article was such a pleasant surprise! I loved talking at Systems We Love and I love talking about legacy architecture in general. Bryan and the Joyent team were very accommodating and understanding. The White House is an amazing place to work (even now), but it's not a system that understands conference talks very well. Wish we could have a video, but it was a heavy lift just getting the bureaucracy okay with the idea that I was going to talk about information that was already public, without naming agencies or projects and without going into detail beyond what was in a user manual and that this was not a security risk.

Re: What Happens When You Mix Java with a 1960 IBM Mainframe

#19

Post by eternalban » Mon, Jan 23, 2017, 9:16 PM UTC

YeGoblynQueenne wrote: post #14

>> It was at this point that the seasoned data architects in the department began expressing their exasperation. “15 years ago, everybody was telling us ‘Get off the mainframe, get on AT&T applications, build these thick clients. Mainframes are out.’ And now thick clients are out, and everybody’s moving to APIs and microservices, which basically are very similar to the thin client that a terminal uses to interact wit…

"15 years ago" doesn't sound right.

Thick clients were being pushed in mid 90s. But then Clipper Chip plans went south ...

Re: What Happens When You Mix Java with a 1960 IBM Mainframe

#20

Post by krylon » Mon, Jan 23, 2017, 9:17 PM UTC

YeGoblynQueenne wrote: post #14

>> It was at this point that the seasoned data architects in the department began expressing their exasperation. “15 years ago, everybody was telling us ‘Get off the mainframe, get on AT&T applications, build these thick clients. Mainframes are out.’ And now thick clients are out, and everybody’s moving to APIs and microservices, which basically are very similar to the thin client that a terminal uses to interact wit…

Wish I could upvote this twice.