A tff.program.FileProgramStateManager is a utility for saving and loading
program state to a file system in a federated program and is used to implement
fault tolerance. In particular, it is intended to only restart the same
simulation and run with the same version of TensorFlow Federated.
A path on the file system to save program state. If this path
does not exist it will be created.
A string to use as the prefix for filenames.
An integer representing the total number of program states to
keep. If the value is zero or smaller, all program states will be kept.
A boolean indicating if the first program state should be
kept, irrespective of whether it is the oldest program state or not.
This is desirable in settings where you would like to ensure full
reproducibility of the simulation, especially in settings where model
weights or optimizer states are initialized randomly. By loading from
the initial program state, one can avoid re-initializing and obtaining