Simple Optimal Wait-free Multireader Registers

TL;DR

This paper introduces simple, optimal wait-free multireader register constructions from atomic registers, improving correctness proofs and efficiency in asynchronous concurrent systems.

Contribution

It presents the first symmetric pure timestamp construction and an optimal global control bit construction for wait-free multireader registers.

Findings

First symmetric pure timestamp construction is optimal in local control bits.

Another construction is optimal in global control bits.

Both constructions are optimal in time.

Abstract

Multireader shared registers are basic objects used as communication medium in asynchronous concurrent computation. We propose a surprisingly simple and natural scheme to obtain several wait-free constructions of bounded 1-writer multireader registers from atomic 1-writer 1-reader registers, that is easier to prove correct than any previous construction. Our main construction is the first symmetric pure timestamp one that is optimal with respect to the worst-case local use of control bits; the other one is optimal with respect to global use of control bits; both are optimal in time.