Browse Prior Art Database

Storage Hierarchy Control System

IP.com Disclosure Number: IPCOM000077668D
Original Publication Date: 1972-Sep-01
Included in the Prior Art Database: 2005-Feb-25
Document File: 2 page(s) / 40K

Publishing Venue

IBM

Related People

Sakalay, FE: AUTHOR

Abstract

The present system provides improved computer speed where a Storage Hierarchy System is in effect. An instruction look-ahead scheme is involved, wherein blocks of data are brought up from slower storage levels to high-speed storage levels before the CPU acquires the data.

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Storage Hierarchy Control System

The present system provides improved computer speed where a Storage Hierarchy System is in effect. An instruction look-ahead scheme is involved, wherein blocks of data are brought up from slower storage levels to high-speed storage levels before the CPU acquires the data.

In the system, the storage demands of the CPU are anticipated. Thus, blocks of storage data are moved from slower levels of storage to the higher speed level before the E-box (See Figure) requests the data operands. As a result, the data requests of the CPU are always serviced by the high-speed buffer.

The CPU is composed of three elements, the S-box, the I-box and the SAP (Storage Address Processor). Instructions are directed from storage to the SAP. The SAP calculates the effective storage address and initiates the movement of pages in the hierarchy. This instruction is then transferred to the I-box where it is further decoded and then placed in the I-stack. The SAP moves on to the next instruction. As the program is executed, a queue of instructions is formed in the I-stack while the corresponding data is stacked in the hierarchy. The SAP executes branch instructions and makes decisions as to which branch to follow. The SAP can easily process instructions faster than the E-box, because the SAP performs one execution per storage reference and need not operate on every instruction in the stream to insure that the corresponding page is moved to the highest level....