z13 - The New Generation of IBM z Systems

General Introduction

Today, January 14, 2015 IBM announced its new generation of the mainframe. The announcement has a really short title 'The IBM z13 (ZG15-0001)'. I know I should give you some marketing talk on CAMS and stuff but I think I'll just concentrate on the technical aspects. And I'm pretty sure that's exactly why you came here for. The new system is simply called IBM z13. Let’s have a look at the name. No more zEC, just plain ‘z’ with a number. And yes, after version 12 comes version 13. So we have our new IBM z13. Looking at the specifications below, this might just be our lucky number ;-) Furthermore we do not longer talk about IBM System z, this has now become IBM z Systems. The model is 2964 and not perhaps the expected 2837. The looks – particulary of the back - have changed in order to gain in functionality. But I’ll come back to that later on.

When we want to summarize the new z13 in a few words, I’d say : a lot, and I mean, A LOT more memory and, for the first time,  the absence of books. Everything has become drawers now. And allthough this might be new for the Enterprise customers, the Business Class customers are already familiar with the concept for some time now. On the BC level, with the drawers came also the Single Chip Modules (SCMs) instead of the Multi Chip Modules (MCMs). Well, it’s no different to the new generation that’s announced now. And of course, we’re curious why IBM dropped the ‘EC’ in the name. Will we fall back to just one model ? Perhaps, instead of a ‘BC’ model, we’ll just have a GA2 announcement later this year with a one frame, one drawer model and more subcapacity settings for that first drawer. But let’s not speculate on the future and let’s have a look at the model that’s been announced just now.

Overview

Here's an overview of the most important new functions and/or improvements divided into three categories. I don't know about you but my eyes aren't getting any better, so you know you can always click on the images for a larger version.

Let's tackle some of the highlights now.

Models and sub-capacity settings

Similar to the zEC12 the new system has four regular models and one large sized model : N30, N63, N96, NC9 and NE1 (the ‘C’ an ‘E’ being hexadecimal representations so that they have 129 and 141 engines. For the regular models, every drawer has 39 PUs and with the NE1 each drawer has 42 PUs.
There are 2 spares designated per system. We see 6 SAPs per book. So if we take e.g. the N30 with 39 PUs, we subtract the 6 SAPs and the 2 spare processors, that leaves us with 31 PUs. Each system also has 1 IFP. And so we reach our 30 processors. As usual processors can be defined as Central Processors (CPs), ICFs, IFLs, zIIPs and optionally as additional SAPs. Here’s the overview of the PU allocation on the IBM z13. You may notice the zAAPs are gone. The z13 is indeed the first system that doesn't support them any more. But as you know, since the z12 we have a 2 to 1 ratio for the zIIPs.

A full processor (the 701 or a specialty engine) has a capacity of 1.695 mips as opposed to 1.514 on the zEC 12. We have again three sub-capacity levels (4-, 5, -6) now for up to 30 CPs.

Memory memory memory

In general we have the same RAIM Memory design as introduced on the z196. But, as I mentioned already, the amount of memory in the system has hugely increased. For the zEC12 the system minimum was 32 GB and went up to 768 GB per book and up to 3 TB for the entire system. Now we see the following picture :

We start at a minimum of 64GB and go already up to an amount of 2.5TB per drawer. There is quite a simple message behind this : the more you can store in memory, the faster your system will operate. Think e.g. about In-Memory Databases where you can have a significant reduction in response time by avoiding I/O waits.
And the good news about this is that memory has become a lot cheaper on the IBM z13. Look at it as with the MSUs on the MLC pricing : the more you buy, the cheaper it becomes.

Processor Speed

There is a slight reduction to the processor speed from 5.5GHz to 5.0GHz. On the one hand this is simply due to environmental considerations like heat generation and power consumption. As we all know there's a limit to this. On the other hand IBM has tackled this with an improved cache structure, the increase of memory and some new functionalities. Eventually this leads to a more powerful processor than we had on the z12 EC.

Here’s a comparison between the zEC12 and the IBM z13 cache. Mind you, for the z13, you only see half of one CPC drawer node.

I won't go into further detail here, but just one example : if the workload was slow due to a high number of cache misses, it's surely expected to run better on the z13.

Upgrades

In short you can upgrade from any z12 EC and z196 to an IBM z13.

Under the covers

But let’s have a closer look at the changes under the covers. Here’s a picture of how an air cooled model looks like on the inside.

Drawers and SCMs

The zEC12 and previous models all used to have Multi Chip Modules (MCMs) with a number of PUs (Processor Units) and SCs (Storage Control) chips. Each PU chip had 4, 5 or 6 cores active. For the zEC12 this meant 27 active processors per MCM on the regular models.

As you can see on the picture, the z13 has four drawers. The z13 N30 has one drawer and let’s have a closer look at such a drawer.

Here we have a top view of the drawer : as a matter of fact we have 8 Single Chip Modules (SCMs) in one drawer. There are two SC SCMs and there are six PU SCMs. These are 8 core chips with 6. 7 or 8 cores active. That way, we get the 39 active processor units per drawer for the regular models. The reason for this evolution : cooling is definitely one of them. The possibility perhaps to consolidate to one single model instead of an EC and a BC model ?

While we have the under the covers picture still in sight : the Support Elements are no longer notepads but have become 1U System x Servers. And we just have display and keyboard where the support elements used to be. And while I’m at it : the HMC comes in two flavours : it’s a mini tower (FC0092) or else there’s also a 1U rack mounted option (FC0094). As a matter of fact, it then is the same x3550 M4 server as the support elements.

More new features

Simultaneous Multi Threading (SMT)

Simultaneous multithreading allows instructions from more than one thread to execute in any given pipeline stage at a time, helping to improve overall throughput. This will be enabled on IFLs and zIIPs only. The goal is to boost performance for Linux, Java, and zIIP workloads.

Up to two active execution threads per core can dynamically share the caches, TLBs and execution resources of each IFL and zIIP core. SMT is designed to improve both core capacity and single thread performance significantly. 

• Simultaneous multithreading allows instructions from more than one thread to execute in any given pipeline stage at a time
• When the SMT is not enabled, a core executes  a single Hardware Thread
• When the SMT facility is enabled, the Hardware Threads within a core share certain hardware resources such as execution units and caches
• When one Hardware Thread in a core is waiting for other hardware resources (typically, while waiting for a storage access), second Hardware Thread in the core can utilize the shared resources in the core rather than remain idle
• SMT helps address memory latency, resulting in overall throughput gains

Single Instruction Multiple Data (SIMD)

SIMD (Single Instruction Multiple Data) provides instruction level parallelism to aid in the performance of complex database operations and provides the ability for a single instruction stream to processmultiple data streams simultaneously rather than one at a time. I gather the illustration below clearly shows the benefit of SIMD.

Another way to demonstrate what is happening is shown in the next illustration

SIMD (Single Instruction Multiple Data)  represents a vector  processing model providing instruction level parallelism.  It provides much needed extensions to aid in the performance of complex database operations and provides the ability for a single instruction stream to process multiple data streams simultaneously rather than one at a time  SIMD can enable applications to scan billions of rows of data per second  This helps accelerate  response times significantly

Workloads that may benefit from Data Parallelism (SIMD)

• High Data Intensity (i.e. data volume)
• High Compute Intensity (i.e. operations on a given byte of data)
• Predictive IT analytics, Advanced Security/Crypto, BI reporting, Prescriptive Analytics, Next-Gen Data Warehousing

Here’s a couple of compilers that will be able to exploit SIMD from the beginning : IBM Java, Enterprise COBOL and Enterprise PL/I.

IBM zAware
IBM zAware improves quite a bit with several new functions like heat maps, improved sorting filtering and tree tables.  This allows you to see more information at once with less scrolling. The most important feature however that is added to IBM zAware is the support for Linux on System z.

Connectivity

The IBM z13 offers a new generation of PCIe Gen3 I/O drawers. This also means the internal bus interconnect speed goes up from 8GBps for PCIe Gen2 to 16GBps for PCIe Gen3. A newly configured system can only contain these new drawers.

Older InfiniBand and PCIe Gen2 drawers can be carried forward, allthough there are specific rules how many of them can be carried forward.

I guess the colours give a pretty good impression of what’s going on here.

Mind that the FICON Express16S card only auto-ngotiates downwards to 4Gb. That’s why FICON Express8S is still available in the new build, but there's an SOD that mentions : IBM plans not to support FICON Express8 on the nex high-end System z server !

The new part for the RoCE card is that the 2 ports are supported now and that it can now support up to 31 logical partitions.

Physical planning

For the physical planning, nothing much has changed. The replacement of the books by drawers does not have any significant impact on the weight of the z13. However there have been made quite some efforts to get better control of energy usage.  IBM has upgraded cooling systems compared to zEC12 with N+2 pumps and blowers. And you know, I mentioned at the beginning that the look and design of the machine had somewhat changed. This was done for the same reason. The zEC12was always blowing its hot air in the same direction. The rear cover has now been redesigned so that you can now control the front to rear airflow. The rear door is designed to allow air flow upwards or rather downwards.

Oh, and by the way, the doors of the z13 can now be locked as well. All 4 doors (front/rear) will arrive with the lock installed. It comes as a standard feature on every z13.It's your choice to use it or not. If locks are used, customer is responsible to open doors for service.

Operating systems support

z/OS Support Plan :

• z/OS V2.1 with PTFs (Exploitation)
• z/OS V1.13 with PTFs (Limited Exploitation)
• z/OS V1.12 with PTFs (End of service support 9/30/2014.)

z/VM Support Plan :

• z/VM V6.3 with PTFs – Exploitation support
• z/VM V6.2 with PTFs – Compatibility plus Crypto Express5S support
• Note: z/VM 5.4 – NOT Compatible even though still in service

z/VSE Support Plan:

• z/VSE V5.2 with PTFs -  Compatibility plus Crypto Express5S (up to 85 LPARs)
• z/VSE V5.1 with PTFs – Compatibility

Linux for System z Support Plan : 

• SUSE SLES 11 (Later releases:  GA support TBD by SUSE.
• Red Hat RHEL 6 (Later releases: GA support TBD by Red Hat.)

zBX and hybrid computing

I think I can be quite short about the zBX. It can now be placed a bit further from the zSystem itself and it has its own HMC. So, far the good news. The 'other' news : you can still upgrade a Model 002 or a Model 003 to a Model 004 but you are not able to buy a new Model 004. Thsi is what IBM so elegantly calls 'investment protection'. If you have invested in a zBX you can keep it and you can upgrade it. But that's it. Sounds to me like IBM is phasing out its zBX project . . .

Software and maintenance pricing

The software pricing is again pretty straightforward this time. It remains the same for MLC : AWLC. Still, there’s a benefit of on average 5%. How is it realized ? Quite simple, there’s a reduction on some softwares depending on the MSUs of the machine, as also happened with the zEC12.

It’s also clear that mobile workload pricing is becoming a very interesting pricing model. I'm not going to elaborate on this again as I treated this already in some previous posts.

Next to the software pricing, there’s also the usual reduction of 2% on the hardware maintenance.

Statements of Direction

Removal of support for auto-negotiation to 2Gbps (FICON Express8S):  IBM z13 EC will be the last high-end server to support FICON Express8S and will be the last high end server to offer ordering of FICON Express8S. FICON Express 8S will not be supported on future high end z Systems servers as carry forward on an upgrade.

Stabilization of z/VM V6.2 support:  The IBM z13 server family is planned to be the last z Systems server supported by z/VM V6.2 and the last z systems server that will be supported where z/VM V6.2 is running as a guest (second level). This is in conjunction with the statement of direction that the IBM z13 server family will be the last to support ESA/390 architecture mode, which z/VM V6.2 requires. z/VM V6.2 will continue to be supported until December 31, 2016.

Product Delivery of z/VM on DVD/Electronic only:   z/VM 6.3 will be the last release of z/VM that will be available on tape.   Subsequent releases will be available on DVD or electronically.

z/VM support for Single Instruction Multiple Data (SIMD): In a future deliverable IBM intends to deliver support to enable z/VM guests to exploit the Vector Facility for z/Architecture (SIMD).

IBM intends to deliver a GDPS/Peer to Peer Remote Copy (GDPS/PPRC) multiplatform resiliency capability for customers who do not run the z/OS operating system in their environment. This solution is intended to provide IBM z Systems customers who run z/VM and their associated guests, for instance, Linux on z Systems, with similar high availability and disaster recovery benefits to those who run on z/OS.

And here’s a really, should I say, surprising one. Or perhaps not.
KVM offering for IBM z Systems: In addition to the continued investment in z/VM, IBM intends to support a Kernel-based Virtual Machine (KVM) offering for z Systems that will host Linux on z Systems guest virtual machines.

So, this means that KVM will be on the same level as z/VM but will only support Linux images. This is perhaps a smart move from IBM : it will reduce cost as well as learning curve to port Intel workloads to the z Systems platform. This is definitely one to keep an eye on.

Documentation

Redbooks
There are some new and updated Redbooks available. They should all be grouped on a special page dedicated to z13 which is normally over here. Here's a short overview of a couple of them..

• New – IBM zNext Technical Introduction, SG24-8250
• New – IBM zNext Technical Guide, SG24-8251
• New – zNext Configuration Setup, SG24-8260
• Updated - IBM System z Connectivity Handbook, SG24-5444
• Updated – IBM System z Functional Matrix, REDP-5157-00

Of course you can also find manuals and stuff in the Library section of Resource Link.
I'll surely come back to the documentation and reference materials in a future post.

Key Dates

Here's just a small selection of items and key dates.

January 14, 2015 :

• Announcement day
• First Day Orders for GA Systems
• Resource Link support (e.g. Manuals available in Library section)

March 9, 2015 :

• Features and functions for the IBM z13
• GA for IBM z13 Models N30, N63, N96, NC9, and NE1
• Upgrades from z196 and zEC12 models

March 13, 2015

• z/VM V6.3 exploitation support for Simultaneous multithreading (SMT)

June 26, 2015 :

• MES features for IBM z13 Models N30, N63, N96, NC9, and NE1
• z/VM V6.3 support for Multi-VSwitch Link Aggregation
• Support for 256 Coupling CHPIDs
• IBM zAware support for Linux on z systems

Let me just finish this with two videos. The people of Redbooks give us a short summary on Youtube of 7 highlights of the new z13.



And if you got through all this, here's a last one, delivering the message to you on a somewhat lighter tone.



Or, hang on, this wasn't the only announcement today, so come back to check for more . . .