110667     RDDRV: Virtual RAM Disk Driver  Version: V1.1, January 1984
 
Submitted by: Walter J. Spanuth, University of Paderborn, Paderborn,
West Germany
 
Operating System: RSX-11M V3.2, V4.0, V4.1  Source Language: MACRO-11
Memory Required: 512KB  Keywords: Device Handlers, Virtual Disk Driver
 
Abstract: This package provides support for the virtual RAM disk
driver RDDRV under the operating system RSX-11M. It
allows the user to dedicate an unused system controlled
partition as a virtual memory disk device. The RAM disk
can be initialized and mounted like any other FILES-11
disk. To speed up I/O operations a dedicated F11ACP is
recommended. The measured performance is better than
twice that of an RL02 disk drive in a PDP-11/23-PLUS
environment. The theoretical transfer rate of the
PDP-11/23-PLUS can be calculated as 512 byte/1.5 msec,
provided that a disk block move operation is
accomplished without any context switch. The driver can
be used as a fast RX01/RX02 floppy device to speed up
disk resident overlayed tasks. Another application might
be a fast work disk for data sampling applications. The
contents of the RAM disk might be saved or restored by
using the standard utilities for FILES-11 disk devices.
 
Media (Service Charge Code): One RX01 Diskette (KA)  Format: FILES-11,
600' Magnetic Tape (MA)  Format: FILES-11