Ensure deterministic data loading#104
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StephenOman merged 1 commit intoNetHack-LE:mainfrom Mar 18, 2026
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This commit resolves a non-determinism issue in `TtyrecDataset` where the order of loaded games could vary between runs. The previous implementation used a single data loading function with a shared lock (`threading.Lock`) for all workers. This created a race condition where multiple threads competed to fetch the next game, resulting in an unpredictable data order. The fix introduces a deterministic assignment of games to each worker: - A new `_make_load_fns` method creates a separate, dedicated data loading function for each batch dimension. - Each function is assigned a unique, non-overlapping sequence of games by striding over the global `gameids` list. This eliminates the need for a shared lock and guarantees a deterministic loading order. The corresponding tests in `test_minibatches` have also been updated to validate this new, deterministic behavior.
This was referenced Mar 9, 2026
StephenOman
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Mar 18, 2026
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This commit resolves a non-determinism issue in
TtyrecDatasetwhere the order of loaded games could vary between runs. This is probably the cause of #88.The previous implementation used a single data loading function with a shared lock (
threading.Lock) for all workers. This created a race condition where multiple threads competed to fetch the next game, resulting in an unpredictable data order.This fix introduces a deterministic assignment of games to each worker:
_make_load_fnsmethod creates a separate, dedicated data loading function for each batch dimension.gameidslist. This eliminates the need for a shared lock and guarantees a deterministic loading order.The corresponding tests in
test_minibatcheshave also been updated to validate this new, deterministic behavior.