# Efficient asynchronous consensus with the value-oblivious adversary scheduler

## Abstract

We consider the power given to adversary scheduler of an asynchronous system and define the *value-oblivious scheduler*. At each step this scheduler determines the next processor to operate based on the full history of the *dynamics* of the execution; the scheduler is oblivious to the intermediate *values* the processors manipulate. We argue that the value-oblivious scheduler captures the possible sources of asynchrony in real systems.

Assuming the value oblivious adversary, we study the asynchronous consensus problem in the shared-memory setting with atomic reads and writes. We present a probabilistic algorithm that obtains consensus in *O*(*n* log^{2}*n*) *total work*. Here, total work is defined as the total number of steps performed by *all* processors collectively. Thus, the amortized work per processor is *O*(log^{2}*n*).

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