IBM Introduces PC-DOS for System z

We've continued to see an increase in the number and scope of operating systems running on the IBM mainframe. Mainframes now run z/OS, Linux on System z, z/VM, z/VSE, z/TPF, OpenSolaris for System z, and UTS. Mantissa is even working on bringing Microsoft Windows to System z. Yet while these operating systems (except Windows) are modern enough for many customers, other customers told me that they wanted even more cutting edge technology, and they wanted additional options for consolidating their most important workloads.

Fortunately IBM listened carefully to customer requirements, including requirements from SHARE (MR0401200900, MR2009040100, and MR0020090401). Today IBM introduces an innovative, new mainframe operating system: PC-DOS for System z.

PC-DOS for System z is compatible with the broad range of PC-DOS and MS-DOS applications available in the marketplace today. However, the System z version of PC-DOS offers unprecedented scalability, performance, availability, and security. In testing conducted together with Marist College using a prerelease version of PC-DOS for System z running under z/VM, each incoming student received a new virtual instance of PC-DOS for each day of the academic year. All PC-DOS instances ran flawlessly, offering every student an average of 0.5 seconds response time per task with no task taking more than 2 seconds. (The students ran a mix of Castle Wolfenstein, Where in the World is Carmen San Diego?, and original Doom workloads, with some batch-oriented XCOPYs and PC-DOS REXX programs.) Marist's installation demonstrated an impressive 99.999% service availability to their students, with only a brief few seconds of interruption when a (now expelled) freshman tripped over a set of FICON cables, triggering an automatic and transparent recovery at Marist's PC-DOS for System z alternate site.

PC-DOS for System z inherits most of the features found in PC-DOS for PCs, but there are a few differences. The PC-DOS kernel has been recompiled to exploit System z hardware decimal floating point, if available, and there is a special high performance zBIOS that supports the new kernel. EMS and XMS memory regions can reside above the bar, in 64-bit storage, and they are now key-protected. (PC-DOS for System z requires a z/Architecture machine.) The "C:\" prompt and about 80% of the COMMAND.COM shell can execute on zIIP engines, although most PC-DOS applications execute on CPs unless individual vendors have zIIP-enabled them. While floppy disk support has been deprecated, IBM extended PC-DOS to support ECKD storage devices, although they appear to PC-DOS users as ordinary hard disks compatible with FDISK. IBM has added a special version of Lotus 1-2-3 to PC-DOS for System z, called "Lotus 1-2-3 for PC-DOS for System z Enterprise Edition with Tivoli OMEGAMON XE Enablement." This version is provided with PC-DOS for System z at no additional charge. IBM issued a Statement of Direction indicating that the company plans to enhance Lotus 1-2-3 to exploit hardware decimal floating point in the future.

This new operating system will be generally available on April 26, 2009. IBM has not yet set exact pricing, but IBM says that PC-DOS for System z will have a new pricing metric known as "Hiper Capacity Quarterly License Charge" (HCQLC) which offers customers increased flexibility and better alignment with quarterly corporate financial reporting. Like z/OS, PC-DOS for System z will be available as a base product plus several optional elements. DFSMSdos, DFMSMSdos,hsm, Security Server (including RACF), RMF, HLASM Toolkit, and even GDDM features are among the optional elements.

Borland's Vice President of Marketing, Sarah Smythe, said, "We at Borland enthusiastically applaud IBM for introducing PC-DOS for System z to an eager market. PC-DOS for System z helps our customers scale their mission critical applications to the Web and beyond. Borland plans to release many of its development tools for this new operating system, including Turbo Pascal for System z which will be available within 30 days."

Gartner's lead platform analyst, Trevor Tanner, noted that "IBM has at least a 5 year lead (0.8 percent probability) in the fast growing enterprise PC-DOS/MS-DOS virtualization market with their announcement (0.82 percent probability). In the midst of a severe global recession (0.99 percent probability), PC-DOS for System z should elicit considerable interest, especially among clients who do not currently do much business with IBM. Gartner advises our clients to subscribe to our latest report (0.2 percent probability) for details on the value of PC-DOS for System z in their enterprises."

by Timothy Sipples April 1, 2009


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Highly amusing! Had me going for a few lines there :)

Posted by: Peter Joseph | Apr 1, 2009 5:39:16 AM


Posted by: Bob | Apr 1, 2009 9:53:33 AM

April 1st uh? DOS on system z...

Posted by: billrain | Apr 1, 2009 10:37:15 AM

I like the idea of DOS better than Windows!

Oh well April 1 is about over.

Posted by: DKM | Apr 1, 2009 5:38:02 PM

I got client asking when will come the day when they can play xbox games on mainframe.

Posted by: otto | Apr 14, 2009 10:56:49 PM

Wow! it is an amazing idea. It can bring large group of desktop business/users consolidated centrally, cost effectively. All most all the application development enviroment available in zSeries can be easily make available to PC-DOS too.
Emirates Airlines, Dubai

Posted by: Suresh Chacko | Jun 21, 2009 6:29:59 AM

Good !!!

Posted by: Niki | Jun 29, 2009 8:53:04 AM

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