Unisys cranks out kicker CMOS and Xeon mainframes

Server maker Unisys is today announcing its second generation of dual-core ClearPath mainframes. These use the company's own CMOS-based mainframe engines and new midrange mainframes based on Intel's Tigerton quad-core Xeon 7300 processors, sporting the same OS 2200 and MCP operating systems that run on the CMOS iron.

A lot of talk in the server market is about processors, but for the kinds of online transaction processing workloads that mainframes and other kinds of big iron boxes run, memory and I/O bandwidth is in many ways more important. And that is why COBOL applications persist on mainframes made by IBM, Unisys, Bull, Siemens, NEC, and Fujitsu, aside from the whole technical and economical issue of porting applications. But single-threaded performance on processors is important for batch processing, which is why mainframe shops always welcome faster engines.

Unisys is the result of the merger of the Sperry and Burroughs mainframe companies. The ClearPath Dorado line runs Sperry's OS 2200 operating system, while the ClearPath Libra products run Burroughs' MCP operating system. For many years, a variant of MCP has been available for Xeon-based machines running Windows, which is used as a kernel and file system for MCP. Last year Unisys ported its OS 2200 operating system to a Linux kernel so it can run on X64 processors.

The engineers at Unisys have created their own instruction set translation layer on these X64 platforms - similar to QuickTransit from Transitive - that translates mainframe instructions to X64 instructions and therefore allows COBOL applications compiled on CMOS engines to run unchanged on the X64 iron.

The net result today is that Unisys mainframe shops which need the most bandwidth and which want real CMOS mainframe engines can buy Dorado 700 or Libra 600 machines. Those that can get by with less MIPS and bandwidth can use midrange and entry Dorado and Libra gear built atop Xeon boxes.

Today, Unisys is rolling out a new ClearPath mainframe, the Dorado 700. It's based on a Unisys-designed, dual-core CMOS mainframe engine rated at 525 MIPS and fabbed by IBM. The chips used in the Dorado 700 line have about 17 per cent more oomph than the engines used in its predecessor, the Dorado 300s. Up to 32 engines can be added to a single box, and OS 2200 supports single images as large as 5,700 MIPS. Customers who need more processing capacity can gang up to four systems whole using Extended Processing Complex-L (XPC-L) clustering software, to deliver over 20,000 aggregate MIPS. The Dorado 700 supports from 8 GB to 16 GB of main memory per cell board (there are eight in the fully configured box), which just shows you how skinny CISC boxes running COBOL can be in terms of main memory.

According to Bill Maclean, vice president of ClearPath programs at Unisys, the target customers for the new Dorado mainframes are those using two- or three-year-old OS 2200 mainframes and who are more I/O- than CPU-bound. Compared to the Dorado 180 line (three generations ago), the Dorado 700 has twice the I/O and network bandwidth. It also has about 2.3 times the CPU performance. While CPU performance has increased over the past few years, I/O bandwidth has hovered around 200,000 I/Os per second (IOPS). The Dorado 700 machines are now at 500,000 IOPS, thanks to a new subsystem. (Customers who bought Dorado 280 and 380 machines probably wish they could just upgrade their I/O and leave their CPUs alone.)