Sheaved memory: architectural support for state saving and restoration in pages systems

Abstract

The concept of read-one/write-many paged memory is introduced and given the name sheaved memory. It is shown that sheaved memory is useful for efficiently maintaining checkpoints in main memory and for providing state saving and state restoration for software that includes recovery blocks or similar control structures. The organization of sheaved memory is described in detail, and a design is presented for a prototype sheaved-memory module that can be built easily from inexpensive, off-the-shelf components. The module can be incorporated within many available computers without altering the computers' hardware design. The concept of sheaved memory is simple and appealing, and its potential for use in a number of software contexts is foreseen.