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Comment by otis_inf | Hacker News Reader

In an article which states "..IBM's z13 mainframe computer, which had been designed for high-volume mobile transactions.", all bets are off with respect to reality. I mean, what does 'designed for high-volume mobile transactions' even mean in the context of having Linux running on the hardware?

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Not sure if this is still correct for the z13 but in general: "System z servers offload such functions as I/O processing, cryptography, memory control, and various service functions (such as hardware configuration management and error logging) to dedicated processors."

(from Wikipedia)

It's called a zIIP engine (http://www-03.ibm.com/systems/z/hardware/features/ziip/) and it utilizes the IFL also (http://www-03.ibm.com/systems/z/os/linux/solutions/ifl.html). We use the zIIP on our z13 basically to offload any work that takes a ton of I/O (DB2 data serves, dataset scans for performance monitoring, RMF and CICS reporting). It ends up saving a lot of money monthly because we are charged by maximum number of MSU's during any four-hour window of the month. The zIIP reduces the number of MSU's needed at any given time. In our case, 5-10.

Back in 2005, I installed SuSe on an s/390 box. If you could throw a lot of memory at it or MIPs, then it would run pretty well, and could be used as a file or email server. But anything that crunched data was horribly slow. Can't say that it's any better now, but if it's utilizing the zIIP, I'm sure it's miles above where it was 10 years ago.

Still, pretty high cost of ownership on the mainframe to get this. I can't imagine many people buying a million dollar mainframe just to run Linux. Seems like those who have a mainframe already would have been like us: let's partition out a Linux instance and try it out.

what does any of that have to do with mobile vs non-mobile? It's like they just added a word for no reason.

To clarify, zIIP processing is only relevant under z/OS. Linux processing runs under IFLs. But that's not to say you can't get some offloading in Linux. By design, mainframes can hardware accelerate some processing. The crytpocards [0] are an example of this.

But you are right. A lot of shops go through a lot of effort to maintain their zIIP window in their z/OS processing. And a big selling point for many mainframe software vendors is that their product's processing is "zIIP-enabled".

[0]: https://share.confex.com/share/120/webprogram/Handout/Sessio... (slide 30)

Yes, you are right there, and thank you for clarifying that. I should have been more clear that the zIIP is useful to Linux through accessing data via z/VM. You can't offload all of the I/O, but you can offload some of it if accessing the mainframe for data. Or so I remember at this point. It's been a few years since leaving my mainframe systems programmer position.

Interesting! Thanks for the info. :)

> I can't imagine many people buying a million dollar mainframe just to run Linux.

The Techcrunch version of this story [1] has an interesting bit on the pricing model, suggesting that the up-front cost will be much lower than usual (but no specific numbers).

By offering an elastic, cloud-like pricing model, [IBM] is hoping to land more customers who might have been scared away previously by the up-front cost of investing in a mainframe. The metered mainframe will still sit inside the customer’s on-premises data center, but billing will be based on how much the customer uses the system, much like a cloud model, Mauri explained.

Of course it depends a lot on the specifics, since IBM does already bill in part based on usage. So this could be either a significant departure in pricing approach, or just marketing a tweak on it.

[1] http://techcrunch.com/2015/08/16/ibm-teams-with-canonical-on...

All of that is standard for a mainframe. Nothing on that list distinguishes this machine for handling mobile transactions as opposed to non mobile ones. IBM hasn't innovated here, they've merely iterated and added a buzzword.

It shows how outmoded mainframes are that they're now selling one that only supports being a fleet of Linux machines. Mainframe customers are no longer scaling their legacy zOS systems, meaning the big mainframe users must be processing their transactions in the Linux cloud now.

In fact mainframes are a growth market for IBM. They are selling quite well.

http://www-03.ibm.com/press/us/en/pressrelease/47029.wss

I am complete naive in this subject area. What would you say to a clueless peer who said, "my laptop has those same features, except built into the CPU (like the AES instructions found in i7 cores) so they have less latency than a mainframe would"?

I cut my teeth on an Amiga and understand the appeal of external processors, but it seems like bringing those features on-die would be better yet. Mainframes seem to be going the other way, though. What am I missing out on?

Probably a realtime(i.e. happens within a guaranteed amount of time) system but the statement is still too vague.

I mean, what does 'designed for high-volume mobile transactions' even mean in the context of having Linux running on the hardware?

Excellent question. Statements like this, grandiose but nonspecific, are intended for managers and those who are looking for a justification to spend money.

Do you have a source on if the LinuxONE Emprorer is actually a z13 underneath? It wouldn't be surprised if the Emperor and Rockhopper are just re-branded z13s and z114s.

If true, here's your specs for the z13:

http://www-01.ibm.com/common/ssi/cgi-bin/ssialias?subtype=SP...

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