  Under an applied external load the global load-sharing fiber bundle model,
with individual fiber strength thresholds sampled randomly from a probability
distribution, will relax to an equilibrium state, or to complete bundle
breakdown. The relaxation can be viewed as taking place in a sequence of steps.
In the first step all fibers weaker than the applied stress fail. As the total
load is redistributed on the surviving fibers, a group of secondary fiber
failures occur, etc. For a bundle with a finite number of fibers the process
stops after a finite number of steps, $t$. By simulation and theoretical
estimates, it is determined how $t$ depends upon the stress, the initial load
per fiber, both for subcritical and supercritical stress. The two-sided
critical divergence is characterized by an exponent -1/2, independent of the
probability distribution of the fiber thresholds.
