IBM System/370 Guide

SECTION 01: SYSTEM HIGHLIGHTS
The System/310 Model 165 is designed to enhance, extend, and broaden
the successful concepts of System/360 architecture. It is a high-
speed, large-scale growth system for System/360 Model 65 and 15 users
that provides significant price performance improvement without the
necessity of major reprogrammdng. The Model 165 is a general purpose
system and offers high performance for both commercial and scientific
applications. It is compatible with the System/310 Model 155.
Transition from System/360 models to the System/310 Model 165 can
be accomplished with a minimum of effort because most current System/360
user programs, I/O devices, and programming systems are upward compatible
with the new system. Upward transition from a Model 165 to a Model 195
can also be accomplished. Additional capabilities will be added to OS
to support new features of the Model 165, thereby providing proven
operating system performance as well as continuity,.
Transition with little or no reprogramming is also provided for
1051/11/111/1080, 1010/1014, and 109/1090/1094/109411 users who are
presently emulating on System/360. Emulators that operate under OS
control on the Model 165 are provided for these systems.
Highlights of the Model 165 are as follows.
• Upward compatibility with most System/360 architecture and
programming has been maintained.
• Internal performance is approximately two to five times that of
the Model 65.
• CPU features of the System/310 Model 165 are as follows:
The Model 165 standard instruction set includes new general purpose
instructions in addition to the powerful System/360 instruction
set. These instructions enhance decimal arithmetic performance,
eliminate the need for multiple move or compare instructions or
move subroutines, and facilitate record blocking and deblocking,
field padding, and storage clearing.
Extended precision floating point is a standard feature to provide
precision of up to 28 hexadecimal digits, equal to approximately
34 decimal digits.
A high-speed multiply feature is available to provide faster
execution of binary and floating-point arithmetic operations.
Execution speed increases by a factor of 2 to 3.
An interval timer of 3.33 ms resolution to improve job accounting
accuracy is standard. A 16.6 ms resolution timer is standard on
the Model 65.
A time of day clock is included to provide more accurate time of
day values than the interval timer. It has a 1 microsecond
resolution.
Separate instruction and execution units are implemented that
provide overlap of instruction fetching, instruction decoding,
operand fetching" and instruction execution to increase internal
performance.
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IBM System/370 Specifications

General

Brand	IBM
Model	System/370
Category	Server
Language	English