10:15 Storage - IBM System/370 Manual

A microfiche document viewer is included in the console unit for
display of customer engineer reference materials. It is expected that
more than half of all Model 165 CE reference materials will be supplied
in microfiche form.
The processor storage configuration plugboard permits automatic
generation of the required processor storage configuration (units
available to the operating system, their addressing, interleaving,
etc.) when power is brought up or upon depression of an Wenter
configuration W push-button.
(See Section 10:15 for further
information.) The exact processor storage configuration in effect
at any given time can be verified by displaying the appropriate image
on the indicator viewer.
The system activity monitor is capable of displaying the average
activity of the CPU and the channels via the system activity meter
located in the main control panel in the system console. The activity
to be displayed is selected via a set of switches. The following can
be displayed" one measurement at a time.
1. Percentage of compute time relative to the:
a. Total time CPU is active
b. Time CPU is active in supervisor state
c. Time CPU is active in problem state
2. Percentage of time the CPU and one or more of the selected
channels are concurrently active (to determine CPU and channel
activity overlap)
3. Percentage of time when all of the selected channels are busy
concurrently (to determine channel activity overlap)
4. Percentage of time when a single selected channel or one or
more of the selected channels are busy (to determine channel
activity)
5. Percentage of time any of the selected channels and the CPU
are busy accessing the selected storage protect key area of
processor storage
A device that provides read-only storage for WCS microcode and
system diagnostics is contained in the system console unit between
the indicator viewer and the document viewer. This device reads
interchangeable magnetic disk cartridges. As already indicated, this
device is used for WCS loading. It is also a debugging tool for the
customer engineer who will load diagnostics from it.
10:15 STORAGE
The Model 165 has a two-level memory system - a very high-speed
buffer storage backed
by
a large processor (main) storage. Prior to
this time, such a concept was implemented only in very large-scale,
high-internal-performance systems, such as System/360 Models 85 and
195. The Model 165 has four-way doubleword interleaved processor
storage with a two-microsecond cycle time, buffered
by
8K or 16K of
high-speed monolithic buffer storage with an 80-nanosecond cycle time.
The use of interleaving and a two-level memory system drastically
reduces the effective storage cycle of the Model 165 and greatly
contributes to the fact that the internal performance of the Model
165 is approximately two to five times that of the Model 65.
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