In a short time, the IBM eServer zSeries 890 has become the mainframe of choice for many VSE customers. Of course, the z890 is the mainframe of choice for many z/OS, z/VM, Linux on zSeries, and z/TPF customers as well. Some z890 features, such as coupling links and zSeries Application Assist Processor (zAAP), apply to z/OS, but not to z/VSE. However, this is a VSE supplement, so this article will focus only on the features and functions that are relevant to a z/VSE environment.  

IBM mainframes such as the S/370-138, IBM 4361, ES/9221, and S/390 Multi-prise 2000 set a high standard. Does the z890 measure up?  

To answer this bold question, this article will go back to the beginning and compare the latest VSE mainframe, the z890 and the very first VSE mainframe, the legendary S/360 Model 30. The winner will be declared the best VSE mainframe of all time!  

Any comparison requires metrics. This exercise uses two criteria: the first is technical excellence and the second is entertainment value.    

Technical Excellence    

Which system has better feeds and speeds?   

CAPACITY  

The zSeries 890 was announced on April 7, 2004. It brings z990 technology within the reach of more VSE customers. The z890 is a single machine, the 2086, with a single hardware model, A04, that has 28 capacity settings. Each z890 is constructed from a basic building block (a “book”) with a Multi-Chip Module (MCM) containing five Processor Units (PUs). Four PUs are available for characterization—as a Central Processor (CP), or as an Integrated Facility for Linux (IFL). A full capacity z890 PU delivers approximately 366 MIPS. A fifth PU is always reserved as a System Assist (SAP). Any PU not characterized exists as a spare.  

The z890 comes standard with 8GB memory. Upgrades are available in 8GB increments, up to a maximum of 32GB.  The S/360-30 was announced April 7, 1964. It brought the innovative capabilities of S/360 within the reach of small and mid-size customers. The S/360-30 had an 8-bit data path and a 1-microsecond machine cycle. The S/360-30 offered approximately 0.03 MIPS and users could pick 16, 32, or 64K bytes of main memory.    

SCALABILITY  

Customers can select the size and number of PUs that make sense for them. Capacity settings range from 4 to 208 MSUs. That means many VSE customers can find a z890 capacity setting that matches their needs. For example, the entry 110 capacity setting is appropriate for some. It has most of the features of other z890 settings, but with smaller I/O configuration and expansion capabilities. A customer can begin with the 110 setting and grow to the 470 setting (four full capacity CPs). The z890 also lets customers add temporary capacity to meet unexpected needs.  

The entry S/360-30 was the same as the largest S/360-30. There was just one engine and one capacity setting. The only variable was the size of main memory. Customers that outgrew the capacity of their S/360-30 could pack up the system, move it to the loading dock, and replace it with a new S/360-40.    

AVAILABILITY  

The z890 is designed for high availability. It incorporates 40 years of mainframe experience and refinement. It also includes transparent PU sparing, dynamic memory sparing, concurrent maintenance, and fault tolerant interconnect design. The result is a very reliable, highly available server.  

The concept of 24x7 availability came later. Most S/360s were leased in 1965. In those days, the IBM monthly lease covered only “prime shift.” In fact, many customers simply shut down the system each night to minimize extra shift charges (and operator expenses).    

CONNECTIVITY  

Expanded connectivity is achieved using z990 innovations such as Logical Channel Subsystem (LCSS). The z890 comes with two LCSSes for up to 512 CHPIDs. The z890 can have up to 420   ESCON (up to 17MBps) channels. Alternatively, it can have up to 80 FICON Express2 (up to 270MBps) or FCP channels. Network connectivity is provided by a two-port OSA Express2 card and up to 40 ports. z890 customers can select 10Gigabit Ethernet, Gigabit Ethernet, 1000BASE-T Ethernet, or Token Ring.  

The S/360-30 offered up to two selector channels (0.25MBps) plus one multiplexor channel. Network connectivity was a new concept and required external TP controllers.    

INTEGRATED FACILITY FOR LINUX (IFL)  

Up to four PUs can be characterized as IFLs. The sum of CPs and IFLs can’t exceed four. IFLs offer a cost-effective server environment for new on demand Linux workloads and infrastructure simplification. Every IFL is a full-capacity PU. The z890 incorporates advanced, superscalar instructions to boost Linux workloads and integration opportunities. In addition, z/VM V5.1 offers unique operational flexibility and systems management benefits that can enhance Linux for zSeries.  

The S/360-30 had no IFL. In 1965, Linux hadn’t yet been invented.    

VIRTUALIZATION  

The z890 offers up to 30 LPARs. In addition, z/VM V5.1 offers operational flexibility and systems management advantages that complement z/VSE. T

he S/360-30 had no LPAR capability. In 1965, VM hadn’t yet been invented. With an S/360-30, it was one mainframe, one operating system.    

OTHER ADVANCED FEATURES  

HiperSockets provides 16 connections and “network in a box” functionality that allows high-speed, any-to-any connectivity among operating system images within a single zSeries server.  

Encryption is necessary to help secure information over the Internet. The z890 includes a CP Assist Cryptographic Feature (CPACF) and five new instructions designed to accelerate symmetric cryptographic operations. An optional Crypto Express2 card is available as well. z/VSE supports both CPACF and Crypto Express2 (as a PCICA card). The PCICA function provides an RSL assist for SSL “handshake” operations.  

The OSA-Integrated Console Controller (OSA-ICC) feature can eliminate the need for external console controllers by using a port on the 1000BASE-T Ethernet card.

The S/360-30 had none of the above.    

VALUE  

Surprisingly, the absolute price of the z890 isn’t much different from the S/360-30 price. If we assume a $1 (U.S.) in 1965 is worth more than $6 (U.S.) in 2005, the z890 is a bargain in comparison with the S/360-30 (using constant U.S. dollars).    

STORAGE  

Disk options for the z890 include IBM TotalStorage DS8000, ESS, and DS6000 series disk. All are high-availability, high-performance designs featuring a large cache, RAID options, and advanced copy functions. For example, the DS8300 is a dual four-way system based on IBM’s POWER5 technology. It offers 32 to 256GB of high-speed cache and 1.1 to 34.8TB of RAID 5 or RAID 10 disk in a single frame.

One tape option for the z890 is the IBM TotalStorage 3494 Virtual Tape Server (VTS). The 3494 VTS stores virtual tape volumes on high-speed disk cache. It later stacks selected volumes on a physical tape cartridge. A robotic arm then stores the cartridge in a 3494 automated tape library.  

Disk options for the S/360-30 included IBM 2311 and 2314 disk subsystems. For example, the 2311 offered 7.25MB per removable pack. Customers could extend the total effective capacity by exchanging packs. For example, Pack A might contain data needed for Application A, while Pack B contained data for Application B. The operator removed Pack A when Application A finished and replaced it with Pack B so Application B could run.  

Tape media in 2005 is largely used for backup, archive, and data exchange. However, in 1965, applications often used tape for processing (i.e., merging, sorting, etc.). The tape used by most S/360-30 systems was the IBM 2401 magnetic tape system. Advanced tape technology at the time featured nine tracks and 1,600 bits per inch. Time to rewind and unload a tape was measured in minutes.    

Entertainment Value  

Man does not live by feeds and speeds alone. Like all aspects of life, your mainframe should be interesting.    

FLASHING LIGHTS  

The S/360-30 panel had rows of lights that were constantly flashing. A “wait light” flickered on and off as processing progressed. The net effect was mesmerizing.

By contrast, there is nothing going on with the z890—no flashing lights.    

COLOR  

The S/360-30 was available in a choice of red, blue, or yellow. We can speculate that, if yellow had been the most popular option, IBM might be known unofficially today as “Big Yellow” rather than “Big Blue.”  

A choice of colors complicated life. For example, IBM paint had to meet very high specifications. A new tape drive added to a string of three-year-old boxes had to match exactly. In addition, if a customer wanted a red tape drive, there might be a delay while a red drive was shipped across the country, even if a blue one was immediately available locally.  

The z890 is available in just one color—black. Not very entertaining, but it makes life simple.    

SOUNDS  

The S/360-30 console used IBM Selectric technology. The type ball chattered as it typed out each message to the operator. Impact printers could be quite loud. A card reader/punch could be noisy as cards were fed into the reader and blank cards were punched. Even spinning disks and tapes made a low-level background noise.  

The z890 console is a CRT that makes no sound. Laser printers are quieter than impact printers. Besides, much of today’s printing is directed to network printers and doesn’t happen in the machine room. Overall, machine rooms in 2005 can be relatively tranquil spots.    

ACTIVITY AND MOVEMENT  

A typical S/360-30 machine room was a beehive of activity. Operators fed cards into the reader, then removed them and put them in their proper place. They fed blank cards into the punch. Operators added and removed paper from the line printer. They exchanged disk packs, often with considerable flair. Operators moved around the tape drives, mounting and dismounting reels and making sure to position tape properly in the vacuum columns.

Even without operators, there was motion in an S/360-30 machine room. One could look down on rotating disk drives and watch the actuators move. Tapes spun on the tape drives, cards moved through the reader/punch, and paper surged through the line printer.  

There isn’t much movement today in a typical z890 machine room. No cards are used. There’s often less printing and paper handling than before. Many executives are comfortable looking at information online and require fewer hard copy reports. Other reports are often distributed electronically, directly to desktop printers. Electronic funds transfer may replace check printing.  

Unlike the IBM 2311, a DS8000 presents nothing much to look at. There’s no disk pack handling, no spinning disks, or moving actuators to view because the disks are enclosed inside modular units. There is little tape handling and no spinning tapes are visible. Smaller, easily handled, fully enclosed cartridges have largely replaced large, hard to handle, open reels.    

PRIDE  

In the early days, many customers proudly displayed their S/360-30 systems for all to see. Some actually placed their machine rooms on the way from the lobby to the executive suite. The wall that most people passed was made of glass (hence the term “Glass House”) so everyone could see the system. It was hoped that visitors would view the system and be impressed. Clearly, any company that used an IBM mainframe was progressive, innovative, and worthy of admiration.  

In 2005, the z890 is seldom so openly displayed. With inexpensive, high- bandwidth communications, the actual machine room can be located almost anywhere. It doesn’t even need to be in the same city. The location of the z890 machine room in 2005 is determined by economic and security considerations.    

And the Winner Is … That Depends   

A full z890 uniprocessor (170 capacity setting) is 12,000 times more powerful than the S/360-30. In addition, even the smallest z890 has 125,000 times the main memory capacity of the largest S/360-30. The z890 is designed for high availability applications and offers advanced storage options. Finally, a z890 is a bargain compared with the S/360-30 on a constant dollar basis (U.S). It is clear the z890 wins on technical excellence.  

We have also shown that a typical S/360-30 machine room was alive with activity and movement. By contrast, modern systems can be relatively sterile and uninteresting. It’s clear the S/360-30 wins on pure entertainment value.  

Picking the overall winner depends on how we weigh the measurement criterion. The S/360-30 was a truly great VSE mainframe in its day. However, nostalgia aside, I suspect most VSE customers would prefer the z890. In 2005, we need all the technical excellence we can get on the job. Boring can be good. We can find entertainment on our own time.  

While the results were somewhat ambiguous, the preponderance of evidence presented here shows that the zSeries 890 is truly the greatest VSE mainframe of all time (so far).

For more information on the z890, visit http://www-1.ibm.com/servers/eserver/zseries/z890/.