Stratus Computer Inc has launched its fault-tolerant Continuum line of symmetric multiprocessing servers, based on Hewlett-Packard Co’s Precision Architecture 7100 RISC and running FTX 3 Unix and the proprietary VOS 13. The one-to-four-way Series 600 and 1200 systems are configured with six and 12 expansion slots respectively and are built around 72MHz and 96MHz PA-7100 implementations. Stratus, which duplexes all components to achieve fault tolerance, says the machines will continue processing for 45 seconds in the event of a total power failure, up from six seconds now. There are nine models, stretching from the 610 – six slots with one processor running at 72MHz, to the 1245 – 12 slots, and four processors running at 96MHz. All ship next month. Stratus has followed in the footsteps of Convex Computer Corp, Concurrent Computer Corp and others by using a new 350Mbps local memory bus in Continuum. It enables daughter boards with from 16Mb to 512Mb to plug directly into each processor board. It says that passing traffic over a local memory bus is one third of the cost of using the system bus, reduces system bus traffic by as much as 75%, and insulates the processor from system bus changes, and enable it to plug in other Precision Architecture RISCs as they emerge. As well as doubling existing system bus throughput to a sustained 128Mbps, Stratus promises that standard Peripheral Component Interconnect devices will plug into Continuums within a year, as part of a project it calls Open I/O. It is devising an Adaptor Module for Open I/O, shielding PCI devices from the fault-tolerant guts of the system, meaning, it says, that PCI devices will not have to be re-invented to support fault tolerance. Applications written to Stratus’s existing p roprietary input-output can be recompiled for PCI under Open I/O. Stratus will move pieces of the proprietary technology to Open I/O in stages, beginning with communications. FTX 3 is based on Unix System V.4.2MP – Stratus is one of the few companies solidly behind the efforts of Novell Inc’s Unix Systems Group, saying it will move to UnixWare 2.0 over time.
