110634     SLDRV: A Memory Resident Disk Driver for RSX-11  Version:
V01.02, June 1983
 
Submitted by: Bruce R. Mitchell, 3M Engineering Systems and Tech Labs,
St. Paul, MN
 
Operating System: RSX-11M V4.0 or later, RSX-11M-PLUS V1.0 or later
Source Language: MACRO-11  Memory Required: 2KB  Keywords: Emulators,
Virtual Disk Driver
 
Abstract: Compilers, assemblers and the Taskbuilders are often slowed
by seek latency of the system disk(s) when accessing system
libraries.  The necessity of many disk seeks has a tendency
to degrade performance from that which would be obained if
disk operations were performed at memory-to-memory speeds.
This problem is noticeable on multi-user development
systems, and is particularly critical on machines with a
single disk.
 
With the increasing popularity of 22-bit PDP-11's
(11/23-PLUS, 11/44, 11/70 and Microll) and decreasing cost
of semiconductor main memory, it is feasible to store
libraries and workfiles in main memory on a "memory resident
disk", where each K word of memory equals 4 disk blocks.
 
This package includes source files, build command files and
runtime control command files to build and use a 512 block
memory resident disk on RSX-11M-PLUS.
 
Restrictions: Operates only on a 22-bit CPU due to large data area
memory requirements.
 
Media (Service Charge Code): One RX01 Diskette (KA)  Format: FILES-11,
600' Magnetic Tape (MA)  Format: FILES-11