Ibis Systems Inc, the Westlake Village, California company that hoped to become a major force in the IBM-compatible mainframe disk business and has had to settle for rather less, has fulfilled its promise to diversify with disk products for the VMEbus market (CI No 1,235). The new Triad parallel transfer disk storage subsystem comprises a high-speed 32-bit VMEbus controller that resides in the host; the Ibis 1012 12Mbyte-per-second transfer rate – using two 6Mbps recording channels – 1Gb unformatted disk drive , and a proprietary software device driver for Unix and other VMEbus machines. Using disk striping techniques where parts of each byte are recorded on different disks, four Triads can be run in parallel to achieve a 48Mbyte-per-second transfer rate to 4Gb of on-line storage. The Ibis-1 VME controller consists of two standard VME double-height circuit boards that need two adjacent backplane slots, and the controller circuitry supports burst rates of up to 28Mbytes-per-second across the VMEbus, and an on-boartd first in-first out buffer enables data to be transferred aaR^s> secondary high-speed port where the VMEbus needs to be freed up for processing in data intensive tasks. There is also a standard 256Kb intelligent cache for speed matching, and further cache can be added in 256Kb blocks. The device driver is written to be supported by SunOS, AT&T Unix System V and Berkeley 4.2 BSD, and can be adapted for other Unix implementations, full source code is supplied, and all control functions can be programmed in C. The speed of the Triad leads Ibis to hope that it will find favour with users of Sun Microsystems’ workstations and of minisupercomputers, and in high speed array and real-time image processing applications such as medical diagnostics. The drives have a three platter head-disk assembly and uses a thin film medium that the company manufactures itself. Single quantity pricing is $34,420, which includes the 1012 drive, VMEbus controller and Unix/VME device driver. A cabinet that can house two drives cosst $2,900. Cresta Marketing Ltd of London SW is handling the Triad in the UK.
