User`s guide

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Device Drivers for OpenVMS™
IntraServer’s OpenVMS™ driver enables the use of Ultra SCSI Differential
disks, tapes and RAID enclosures, such as Compaq’s StorageWorks line of
disk enclosures, to maximize the VAX™ system’s I/O throughput and
storage capacity. IntraServer’s OpenVMS™ drivers are optimized for
minimum load on the system processor(s) by use of a loadable SCRIPT to
handle low level SCSI operations and minimize the number of interrupt
requests to the system. For the case of small I/Os, IntraServer’s OpenVMS™
driver will only interrupt the host once for each I/O, compared with several
interrupts per I/O for other SCSI adapters. IntraServer’s Ultra SCSI
OpenVMS™ drivers also feature:
IntraServer’s Digital OpenVMS™-VAX™
driver features:
•
Supports Ultra SCSI at speeds up to 40MBytes/Sec per channel (Ultra-
SCSI peak synchronous rate. Your system will be limited to the
system’s bus bandwidth, which can be below this peak rate)
•
Supports over 5000 single block I/Os per second per channel
•
Supports synchronous negotiation (including Fast/Ultra SCSI)
•
Minimum interrupt per I/O script technology for maximum I/O
throughput with minimum CPU overhead
•
Supports up to 7 disks per channel
•
vmsinstal.com support for simple installation
•
Supports wide negotiation
•
Supports tagged command queuing
•
Supports multiple Logical Unit Numbers (LUNs)
•
Supports Disconnect/Reselect
• Supports differential SCSI
• Supports Host Based Shadowing