Unisys Corp received the odd quizzical look when it claimed that its dual processor A17H – a direct descendent of the Burroughs B7900 – walked all over a four processor IBM 3090-400 in transaction processing benchmarks (CI No 1,029), so what is the basis of the Unisys claim? The performance comparisons are based on the […]
Unisys Corp received the odd quizzical look when it claimed that its dual processor A17H – a direct descendent of the Burroughs B7900 – walked all over a four processor IBM 3090-400 in transaction processing benchmarks (CI No 1,029), so what is the basis of the Unisys claim? The performance comparisons are based on the IMS/VS Fast Path Version 2 Release 2 Benchmark, OneKay, specifically designed to demonstrate the ability of an IBM mainframe to process 1,000 transactions a second in a point-of sale environment, with 13m accounts and 2,000 stores. Unisys says it ran the benchmark tests, consisting of three high volume, on-line applications: credit authorisation, credit limit and debit and claims that for each application, the A17H performed 8% to 20% more transactions per second than the 3090 400, and at a much lower cost per transaction. The A17H machine had 192Mb memory – it’s a 48-bit word machine, eight disk units for database audition, and standard Unisys operating system software and data base management software – MCP and DMS II, presumably, although the company does not spell that out. The IBM machine was a 3090-400 – no mention of whether it was a straight 400 or an E but presumably the former, since otherwise Unisys would have stressed the E. It had 128Mb of main memory, 256Mb of extended memory and 86 disk units for the database. The operating software was MVS/XA SP 2.1.1. The database manager was IMS/VS Fast Path 2.2. In the debit application, the A17 did 1,009 transactions per second, the 3090 did 933 – an 8% edge for the A17H. In the credit authorisation, the A17 scored 1,179 transactions per second, says Unisys, whereas the 3090 could manage only 1,062, an 11% margin for the A17. And in the credit limit application, the A17 really came into its own, recording 1,246 transactions per second, where the 3090 was stuck down at 1,033, a 20% margin for the A17. Unisys reckons that the A17 scored its victory by virtue of architectural features that enable efficient execution of multiple tasks and implement efficient communication between user programs and operating system software. The A17 also contains two specialised processors that implement key operating system functions in hardware for additional speed. The input-output processor is also claimed to reduce the central processor time required to manage input and output by a factor of three to four. A task control processor performs many operating system functions associated with managing programs, thereby reducing the task switching overhead by a factor of 10. All of which should make the UK Alliance & Leicester Building Society happy that it is firmly in the A-series camp for all its major on-line banking and financial applications.