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.
> 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.
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".
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.
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.