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Pepijn
41166b39fb
* fix(datasets): expose a generator on EpisodeAwareSampler for distributed shuffle sync In distributed training, accelerate can only synchronize the shuffle permutation across ranks when the sampler exposes a generator attribute. EpisodeAwareSampler shuffled via the global torch RNG, so disjoint batch shards relied on every rank's global CPU RNG staying in lockstep forever; any rank-asymmetric RNG consumption (e.g. eval rollouts on the main process only) silently desynced the permutations and ranks trained on overlapping/missing samples. * fix(train): seed sampler generator and gate dataset download per node - Pass a generator seeded with cfg.seed to EpisodeAwareSampler so accelerator.prepare registers it as the synchronized RNG and the shuffle order is reproducible. - Gate the initial make_dataset call on is_local_main_process instead of is_main_process: the global main process only exists on node 0, so on every other node all local ranks were downloading the dataset and building the Arrow cache concurrently.