Cray J90
| Company type | Product line |
|---|---|
| Industry | Supercomputing |
| Predecessor | Cray Y-MP EL |
| Founded | 1994 |
| Founder | Cray Research |
| Products | Vector processor supercomputers |
| Parent | Cray Research |
The Cray J90 family, internally designated as Jedi, was an air-cooled vector processor supercomputer launched by Cray Research in 1994. This series was a development of the Cray Y-MP EL minisupercomputer, preserving full compatibility with Y-MP software by operating on the same UNICOS operating system. Subsequent versions accommodated up to 32 CMOS processors running at 100 MHz, supported a maximum of 4 GB memory, and delivered a bandwidth of 48 GB/s. Although it did not match the raw power of the contemporary Cray T90, the J90 provided robust computational capabilities at a more affordable cost.
Initial J90 systems incorporated an Input/Output Subsystem (IOS) known as IOS Model V, which utilized the VME64 architecture alongside SPARC I/O processors running the VxWorks RTOS. This IOS-V emulated the IOS Model E found in larger Cray Y-MP machines to minimize modifications to UNICOS. Employing standard VME modules enabled compatibility with a broad array of common peripheral devices.
Models
The J90 series was available in three variants: the J98, supporting up to eight processors; the J916, capable of handling up to 16 processors; and the J932, which could accommodate as many as 32 processors. Each processor was composed of two separate chips—a scalar chip and a vector chip—with the scalar component featuring a modest (128 word) data cache designed to enhance scalar processing efficiency, complementing Cray’s established instruction caching methods.
In 1997, Cray introduced the J90se (Scalar Enhanced) lineup, which doubled scalar clock speeds to 200 MHz while keeping the vector chip frequency steady at 100 MHz. This upgrade also incorporated support for the GigaRing I/O architecture used in the Cray T3E and Cray SV1, supplanting the earlier IOS-V. Additionally, processors from the SV1 series could be installed in J90 or J90se chassis, enabling further performance improvements without changing hardware enclosures.