Virtual memory address translation mechanism with controlled data persistence
US4638426A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 19, 1983 |
| Grant date | Jan 20, 1987 |
| Priority date | — |
| Expiry date | Sep 19, 2003 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F2212/683
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A memory address translation and related control system for performing the dual functions of converting virtual memory addresses generated by the CPU into real memory addresses in a highly efficient and versatile manner and for controlling certain memory functions such as journalling. The address translation function comprises two steps, the first comprising converting the virtual address into a second virtual address or an effective address and finally the step of converting the effective address into a real memory address. The first step utilizes a set of special registers addressable by a small field to the CPU generated virtual address which converts the virtual address into an expanded form. The second or effective address is then used as the subject of the second or address translation step. To greatly enhance the translation of frequently used virtual addresses, a special set of translation tables referred to herein as a Translation Look-Aside, Buffer (TLB) contain current effective to real address translations for use where frequently referenced addresses are requested. The TLBs are addressed using a subset of the effective address whereupon the contents of the addressed TL…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.