bdm@ciprico.mn.org (Bill D. Moren) (09/18/87)
RIMFIRE 3200 VMEbus HIGH PERFORMANCE SMD-E DISK CONTROLLER Ciprico Inc.'s Rimfire 3200 SMD-E controller was developed to provide UNIX based systems with the highest levels of disk performance. Advanced data management techniques, a hardware architecture designed for speed, and extensive UNIX software support are combined to make the Rimfire 3200 the highest performance board available. * 512 Kbyte Lookahead * 30 Mbyte/sec. VMEbus Cache Buffer Transfer Rates * Cross-track Lookahead * 24 MHz Disk Serial Rates Caching * Extensive Command * Circular Command Queue Optimization Software Interface * Software Support Including * 48-bit ECC UNIX Drivers A 512-Kbyte cache memory and high performance micro processor, coupled with high speed disk and bus interfaces, are the foundation for improving disk throughput. A large segmented cache allows multiple tracks of disk data to reside in controller resident memory, where access times are measured in microseconds, not milliseconds. The microprocessor's computing power is ap plied to cache management functions. Additionally, the micro processor also processes disk requests from the system, using advanced algorithms that optimize controller and disk operations. To increase throughput, lookahead caching takes advantage of the tendency for data files to be stored sequentially on disks. Disk data subsequent to a specific request are pre-read into the controller's cache memory. Because files may span track boundaries, cross-track lookahead pre-reads multiple tracks with out losing revolutions. Future sequential requests are then satisfied directly from the cache. This technique, developed with an understanding of file systems, eliminates costly seek and rotational delays. Multiple circular command queues, designed with system soft ware in mind, link the operating system and the Rimfire 3200 controller. Each queue, with a command capacity exceeding prac tical limits, receives requests from the operating system driver asynchronously and without handshake timing restrictions. With access to all pending disk requests, the Rimfire 3200 controller will reduce physical latency times by optimizing disk head motion and minimizing the disk accesses. With a transfer rate capability of 30 Megabytes/second, the combination of Ciprico's proprietary Short Burst FIFO gate array and VMEbus interface maximize system bus utilization. By moving data across the bus at a rate only limited by the capability of most memory boards, the Rimfire 3200 controller uses a small fraction of the available bus bandwidth for data transfers. Disk drive serial data rates of up to 24 MHz provide VMEbus system architects with the tools to build a system that has ample storage capacity at the highest possible data rates. Even if initial implementations use SMD, HSMD, or ESMD drives, upgrading to SMD-E drives won't require a controller change. Regardless of the drives selected, intelligent management techniques, such as automatic overlapped seeks on multiple drives, insure maximum performance. Extensive software support, vital to easy integration, shortens the lengthy start-up process most system integrators are used to. Support starts with a operating system driver (for either the System V or BSD 4.2 versions of the UNIX operating system) developed to take advantage of all the functionality designed into the Rimfire 3200 controller. Customer support engineers, experienced with system integration, will provide any needed assistance during your integration and evaluation. Soft ware compatibility with the Rimfire 3400 ESDI disk controller allows expanding your system's capability by only adding new hardware to your existing software. The Rimfire 3200 controller is available today with a list price of $2695. For more information on the Rimfire 3200 controller, or any of Ciprico's VMEbus, Multibus I, or Multibus II compatible mass storage controllers, contact Bill Moren at Ciprico: Ciprico Inc. 2955 Xenium Lane Plymouth, MN 55441 (612) 559-2034 or at: bdm@ciprico.mn.org