Fast non-blocking atomic commit: an inherent trade-off

This paper investigates the time-complexity of the non-blocking atomic commit (NBAC) problem in a synchronous distributed model where t out of n processes may fail by crashing. We exhibit for t ≥ 3 an inherent trade-off between the fast abort property of NBAC, i.e., aborting a transaction as soon as possible if some process votes “no,” and the fast commit property, i.e., committing a transaction as soon as possible when all processes vote “yes” and no process crashes. We also give two algorithms: the first satisfies fast commit and a weak variant of fast abort, whereas the second satisfies fast abort and a weak variant of fast commit. For t ≤ 2, we show an algorithm that satisfies fast abort as well as fast commit.