GenDGRLExperienceReplay#
- class torchrl.data.datasets.GenDGRLExperienceReplay(*args, use_ray_service=False, service_backend=None, service_backend_options=None, **kwargs)[source]#
Gen-DGRL Experience Replay dataset.
This dataset accompanies the paper “The Generalization Gap in Offline Reinforcement Learning”.
Arxiv: https://arxiv.org/abs/2312.05742
GitHub: facebookresearch/gen_dgrl
The data format follows the TED convention.
This class gives you access to the ProcGen dataset. Each dataset_id registered in GenDGRLExperienceReplay.available_datasets consists in a particular task (“bigfish”, “bossfight”, …) separated from a category (“1M_E”, “1M_S”, …) by a comma (“bigfish-1M_E”, …).
During download and preparation, the data is downloaded as .tar files, where each trajectory is stored independently in a .npy file. Each of these files is extracted, written in a contiguous mmap tensor, and then cleared. This process can take several minutes per dataset. On a cluster, it is advisable to first run the download and preprocessing separately on different workers or processes for different datasets, and launch the training script in a second time.
- Parameters:
dataset_id (str) – the dataset to be downloaded. Must be part of
GenDGRLExperienceReplay.available_datasets.batch_size (int, optional) – Batch-size used during sampling. Can be overridden by data.sample(batch_size) if necessary.
- Keyword Arguments:
root (Path or str, optional) – The
GenDGRLExperienceReplaydataset root directory. The actual dataset memory-mapped files will be saved under <root>/<dataset_id>. If none is provided, it defaults to ~/.cache/torchrl/atari.gen_dgrl`.download (bool or str, optional) – Whether the dataset should be downloaded if not found. Defaults to
True. Download can also be passed as"force", in which case the downloaded data will be overwritten.sampler (Sampler, optional) – the sampler to be used. If none is provided a default RandomSampler() will be used.
writer (Writer, optional) – the writer to be used. If none is provided a default RoundRobinWriter() will be used.
collate_fn (callable, optional) – merges a list of samples to form a mini-batch of Tensor(s)/outputs. Used when using batched loading from a map-style dataset.
pin_memory (bool) – whether pin_memory() should be called on the rb samples.
prefetch (int, optional) – number of next batches to be prefetched using multithreading.
transform (Transform, optional) – Transform to be executed when sample() is called. To chain transforms use the
Composeclass.
- Variables:
available_datasets – a list of accepted entries to be downloaded. These names correspond to the directory path in the huggingface dataset repository. If possible, the list will be dynamically retrieved from huggingface. If no internet connection is available, it a cached version will be used.
Examples
>>> import torch >>> torch.manual_seed(0) >>> from torchrl.data.datasets import GenDGRLExperienceReplay >>> d = GenDGRLExperienceReplay("bigfish-1M_E", batch_size=32) >>> for batch in d: ... break >>> print(batch)
- add(data: TensorDictBase) int#
Add a single element to the replay buffer.
- Parameters:
data (Any) – data to be added to the replay buffer
- Returns:
index where the data lives in the replay buffer.
- append_transform(transform: Transform, *, invert: bool = False) ReplayBuffer#
Appends transform at the end.
Transforms are applied in order when sample is called.
- Parameters:
transform (Transform) – The transform to be appended
- Keyword Arguments:
invert (bool, optional) – if
True, the transform will be inverted (forward calls will be called during writing and inverse calls during reading). Defaults toFalse.
Example
>>> rb = ReplayBuffer(storage=LazyMemmapStorage(10), batch_size=4) >>> data = TensorDict({"a": torch.zeros(10)}, [10]) >>> def t(data): ... data += 1 ... return data >>> rb.append_transform(t, invert=True) >>> rb.extend(data) >>> assert (data == 1).all()
- classmethod as_remote(remote_config=None)#
Creates an instance of a remote ray class.
- Parameters:
cls (Python Class) – class to be remotely instantiated.
remote_config (dict) – the quantity of CPU cores to reserve for this class. Defaults to torchrl.collectors.distributed.ray.DEFAULT_REMOTE_CLASS_CONFIG.
- Returns:
A function that creates ray remote class instances.
- property batch_size#
The batch size of the replay buffer.
The batch size can be overridden by setting the batch_size parameter in the
sample()method.It defines both the number of samples returned by
sample()and the number of samples that are yielded by theReplayBufferiterator.
- client() T#
Return
selffor the zero-overhead direct backend.
- property data_path#
Path to the dataset, including split.
- property data_path_root#
Path to the dataset root.
- delete()#
Deletes a dataset storage from disk.
- dumps(path)#
Saves the replay buffer on disk at the specified path.
- Parameters:
path (Path or str) – path where to save the replay buffer.
Examples
>>> import tempfile >>> import tqdm >>> from torchrl.data import LazyMemmapStorage, TensorDictReplayBuffer >>> from torchrl.data.replay_buffers.samplers import PrioritizedSampler, RandomSampler >>> import torch >>> from tensordict import TensorDict >>> # Build and populate the replay buffer >>> S = 1_000_000 >>> sampler = PrioritizedSampler(S, 1.1, 1.0) >>> # sampler = RandomSampler() >>> storage = LazyMemmapStorage(S) >>> rb = TensorDictReplayBuffer(storage=storage, sampler=sampler) >>> >>> for _ in tqdm.tqdm(range(100)): ... td = TensorDict({"obs": torch.randn(100, 3, 4), "next": {"obs": torch.randn(100, 3, 4)}, "td_error": torch.rand(100)}, [100]) ... rb.extend(td) ... sample = rb.sample(32) ... rb.update_tensordict_priority(sample) >>> # save and load the buffer >>> with tempfile.TemporaryDirectory() as tmpdir: ... rb.dumps(tmpdir) ... ... sampler = PrioritizedSampler(S, 1.1, 1.0) ... # sampler = RandomSampler() ... storage = LazyMemmapStorage(S) ... rb_load = TensorDictReplayBuffer(storage=storage, sampler=sampler) ... rb_load.loads(tmpdir) ... assert len(rb) == len(rb_load)
- empty(empty_write_count: bool = True)#
Empties the replay buffer and reset cursor to 0.
- Parameters:
empty_write_count (bool, optional) – Whether to empty the write_count attribute. Defaults to True.
- extend(tensordicts: TensorDictBase, *, update_priority: bool | None = None) Tensor#
Extends the replay buffer with a batch of data.
- Parameters:
tensordicts (TensorDictBase) – The data to extend the replay buffer with.
- Keyword Arguments:
update_priority (bool, optional) – Whether to update the priority of the data. Defaults to True.
- Returns:
The indices of the data that were added to the replay buffer.
- property initialized: bool#
Whether the replay buffer has been initialized.
- insert_transform(index: int, transform: Transform, *, invert: bool = False) ReplayBuffer#
Inserts transform.
Transforms are executed in order when sample is called.
- Parameters:
index (int) – Position to insert the transform.
transform (Transform) – The transform to be appended
- Keyword Arguments:
invert (bool, optional) – if
True, the transform will be inverted (forward calls will be called during writing and inverse calls during reading). Defaults toFalse.
- property is_alive: bool#
Whether this direct replay buffer remains available.
- loads(path)#
Loads a replay buffer state at the given path.
The buffer should have matching components and be saved using
dumps().- Parameters:
path (Path or str) – path where the replay buffer was saved.
See
dumps()for more info.
- next()#
Returns the next item in the replay buffer.
This method is used to iterate over the replay buffer in contexts where __iter__ is not available, such as
RayReplayBuffer.
- preprocess(fn: Callable[[TensorDictBase], TensorDictBase], dim: int = 0, num_workers: int | None = None, *, chunksize: int | None = None, num_chunks: int | None = None, pool: mp.Pool | None = None, generator: torch.Generator | None = None, max_tasks_per_child: int | None = None, worker_threads: int = 1, index_with_generator: bool = False, pbar: bool = False, mp_start_method: str | None = None, num_frames: int | None = None, dest: str | Path) TensorStorage#
Preprocesses a dataset and returns a new storage with the formatted data.
The data transform must be unitary (work on a single sample of the dataset).
The dataset can subsequently be deleted using
delete().- Parameters:
fn (Callable[[TensorDictBase], TensorDictBase]) – transform to apply to each sample.
dim (int, optional) – dimension along which the dataset is mapped. Defaults to
0.num_workers (int, optional) – number of worker processes to use. Defaults to
None.
- Keyword Arguments:
chunksize (int, optional) – chunk size forwarded to
map().num_chunks (int, optional) – number of chunks forwarded to
map().pool (multiprocessing.Pool, optional) – worker pool forwarded to
map().generator (torch.Generator, optional) – random generator forwarded to
map().max_tasks_per_child (int, optional) – maximum number of tasks per child process forwarded to
map().worker_threads (int, optional) – number of threads per worker forwarded to
map(). Defaults to1.index_with_generator (bool, optional) – whether to index with the generator when mapping. Defaults to
False.pbar (bool, optional) – whether to display a progress bar. Defaults to
False.mp_start_method (str, optional) – multiprocessing start method forwarded to
map().dest (path or equivalent) – a path to the location of the new dataset.
num_frames (int, optional) – if provided, only the first num_frames will be transformed. This is useful to debug the transform at first.
Returns: A new storage to be used within a
ReplayBufferinstance.Examples
>>> from torchrl.data.datasets import MinariExperienceReplay >>> >>> data = MinariExperienceReplay( ... list(MinariExperienceReplay.available_datasets)[0], ... batch_size=32 ... ) >>> print(data) MinariExperienceReplay( storages=TensorStorage(TensorDict( fields={ action: MemoryMappedTensor(shape=torch.Size([1000000, 8]), device=cpu, dtype=torch.float32, is_shared=True), episode: MemoryMappedTensor(shape=torch.Size([1000000]), device=cpu, dtype=torch.int64, is_shared=True), info: TensorDict( fields={ distance_from_origin: MemoryMappedTensor(shape=torch.Size([1000000]), device=cpu, dtype=torch.float64, is_shared=True), forward_reward: MemoryMappedTensor(shape=torch.Size([1000000]), device=cpu, dtype=torch.float64, is_shared=True), goal: MemoryMappedTensor(shape=torch.Size([1000000, 2]), device=cpu, dtype=torch.float64, is_shared=True), qpos: MemoryMappedTensor(shape=torch.Size([1000000, 15]), device=cpu, dtype=torch.float64, is_shared=True), qvel: MemoryMappedTensor(shape=torch.Size([1000000, 14]), device=cpu, dtype=torch.float64, is_shared=True), reward_ctrl: MemoryMappedTensor(shape=torch.Size([1000000]), device=cpu, dtype=torch.float64, is_shared=True), reward_forward: MemoryMappedTensor(shape=torch.Size([1000000]), device=cpu, dtype=torch.float64, is_shared=True), reward_survive: MemoryMappedTensor(shape=torch.Size([1000000]), device=cpu, dtype=torch.float64, is_shared=True), success: MemoryMappedTensor(shape=torch.Size([1000000]), device=cpu, dtype=torch.bool, is_shared=True), x_position: MemoryMappedTensor(shape=torch.Size([1000000]), device=cpu, dtype=torch.float64, is_shared=True), x_velocity: MemoryMappedTensor(shape=torch.Size([1000000]), device=cpu, dtype=torch.float64, is_shared=True), y_position: MemoryMappedTensor(shape=torch.Size([1000000]), device=cpu, dtype=torch.float64, is_shared=True), y_velocity: MemoryMappedTensor(shape=torch.Size([1000000]), device=cpu, dtype=torch.float64, is_shared=True)}, batch_size=torch.Size([1000000]), device=cpu, is_shared=False), next: TensorDict( fields={ done: MemoryMappedTensor(shape=torch.Size([1000000, 1]), device=cpu, dtype=torch.bool, is_shared=True), info: TensorDict( fields={ distance_from_origin: MemoryMappedTensor(shape=torch.Size([1000000]), device=cpu, dtype=torch.float64, is_shared=True), forward_reward: MemoryMappedTensor(shape=torch.Size([1000000]), device=cpu, dtype=torch.float64, is_shared=True), goal: MemoryMappedTensor(shape=torch.Size([1000000, 2]), device=cpu, dtype=torch.float64, is_shared=True), qpos: MemoryMappedTensor(shape=torch.Size([1000000, 15]), device=cpu, dtype=torch.float64, is_shared=True), qvel: MemoryMappedTensor(shape=torch.Size([1000000, 14]), device=cpu, dtype=torch.float64, is_shared=True), reward_ctrl: MemoryMappedTensor(shape=torch.Size([1000000]), device=cpu, dtype=torch.float64, is_shared=True), reward_forward: MemoryMappedTensor(shape=torch.Size([1000000]), device=cpu, dtype=torch.float64, is_shared=True), reward_survive: MemoryMappedTensor(shape=torch.Size([1000000]), device=cpu, dtype=torch.float64, is_shared=True), success: MemoryMappedTensor(shape=torch.Size([1000000]), device=cpu, dtype=torch.bool, is_shared=True), x_position: MemoryMappedTensor(shape=torch.Size([1000000]), device=cpu, dtype=torch.float64, is_shared=True), x_velocity: MemoryMappedTensor(shape=torch.Size([1000000]), device=cpu, dtype=torch.float64, is_shared=True), y_position: MemoryMappedTensor(shape=torch.Size([1000000]), device=cpu, dtype=torch.float64, is_shared=True), y_velocity: MemoryMappedTensor(shape=torch.Size([1000000]), device=cpu, dtype=torch.float64, is_shared=True)}, batch_size=torch.Size([1000000]), device=cpu, is_shared=False), observation: TensorDict( fields={ achieved_goal: MemoryMappedTensor(shape=torch.Size([1000000, 2]), device=cpu, dtype=torch.float64, is_shared=True), desired_goal: MemoryMappedTensor(shape=torch.Size([1000000, 2]), device=cpu, dtype=torch.float64, is_shared=True), observation: MemoryMappedTensor(shape=torch.Size([1000000, 27]), device=cpu, dtype=torch.float64, is_shared=True)}, batch_size=torch.Size([1000000]), device=cpu, is_shared=False), reward: MemoryMappedTensor(shape=torch.Size([1000000, 1]), device=cpu, dtype=torch.float64, is_shared=True), terminated: MemoryMappedTensor(shape=torch.Size([1000000, 1]), device=cpu, dtype=torch.bool, is_shared=True), truncated: MemoryMappedTensor(shape=torch.Size([1000000, 1]), device=cpu, dtype=torch.bool, is_shared=True)}, batch_size=torch.Size([1000000]), device=cpu, is_shared=False), observation: TensorDict( fields={ achieved_goal: MemoryMappedTensor(shape=torch.Size([1000000, 2]), device=cpu, dtype=torch.float64, is_shared=True), desired_goal: MemoryMappedTensor(shape=torch.Size([1000000, 2]), device=cpu, dtype=torch.float64, is_shared=True), observation: MemoryMappedTensor(shape=torch.Size([1000000, 27]), device=cpu, dtype=torch.float64, is_shared=True)}, batch_size=torch.Size([1000000]), device=cpu, is_shared=False)}, batch_size=torch.Size([1000000]), device=cpu, is_shared=False)), samplers=RandomSampler, writers=ImmutableDatasetWriter(), batch_size=32, transform=Compose( ), collate_fn=<function _collate_id at 0x120e21dc0>) >>> from torchrl.envs import CatTensors, Compose >>> from tempfile import TemporaryDirectory >>> >>> cat_tensors = CatTensors( ... in_keys=[("observation", "observation"), ("observation", "achieved_goal"), ... ("observation", "desired_goal")], ... out_key="obs" ... ) >>> cat_next_tensors = CatTensors( ... in_keys=[("next", "observation", "observation"), ... ("next", "observation", "achieved_goal"), ... ("next", "observation", "desired_goal")], ... out_key=("next", "obs") ... ) >>> t = Compose(cat_tensors, cat_next_tensors) >>> >>> def func(td): ... td = td.select( ... "action", ... "episode", ... ("next", "done"), ... ("next", "observation"), ... ("next", "reward"), ... ("next", "terminated"), ... ("next", "truncated"), ... "observation" ... ) ... td = t(td) ... return td >>> with TemporaryDirectory() as tmpdir: ... new_storage = data.preprocess(func, num_workers=4, pbar=True, mp_start_method="fork", dest=tmpdir) ... rb = ReplayBuffer(storage=new_storage) ... print(rb) ReplayBuffer( storage=TensorStorage( data=TensorDict( fields={ action: MemoryMappedTensor(shape=torch.Size([1000000, 8]), device=cpu, dtype=torch.float32, is_shared=True), episode: MemoryMappedTensor(shape=torch.Size([1000000]), device=cpu, dtype=torch.int64, is_shared=True), next: TensorDict( fields={ done: MemoryMappedTensor(shape=torch.Size([1000000, 1]), device=cpu, dtype=torch.bool, is_shared=True), obs: MemoryMappedTensor(shape=torch.Size([1000000, 31]), device=cpu, dtype=torch.float64, is_shared=True), observation: TensorDict( fields={ }, batch_size=torch.Size([1000000]), device=cpu, is_shared=False), reward: MemoryMappedTensor(shape=torch.Size([1000000, 1]), device=cpu, dtype=torch.float64, is_shared=True), terminated: MemoryMappedTensor(shape=torch.Size([1000000, 1]), device=cpu, dtype=torch.bool, is_shared=True), truncated: MemoryMappedTensor(shape=torch.Size([1000000, 1]), device=cpu, dtype=torch.bool, is_shared=True)}, batch_size=torch.Size([1000000]), device=cpu, is_shared=False), obs: MemoryMappedTensor(shape=torch.Size([1000000, 31]), device=cpu, dtype=torch.float64, is_shared=True), observation: TensorDict( fields={ }, batch_size=torch.Size([1000000]), device=cpu, is_shared=False)}, batch_size=torch.Size([1000000]), device=cpu, is_shared=False), shape=torch.Size([1000000]), len=1000000, max_size=1000000), sampler=RandomSampler(), writer=RoundRobinWriter(cursor=0, full_storage=True), batch_size=None, collate_fn=<function _collate_id at 0x168406fc0>)
- query(predicate: Callable[[Trajectory], bool] | None = None, *, trajectory_key: NestedKey | None = None) list[Trajectory]#
Filters the stored trajectories with a query predicate.
Splits the buffer content into trajectories (see
iter_trajectories()) and returns those matching the predicate asTrajectoryviews.- Parameters:
predicate (Callable[[Trajectory], bool], optional) – a
TrajectoryPredicatebuilt fromtraj, or any callable mapping a trajectory to a boolean. Defaults to None (return all trajectories).- Keyword Arguments:
trajectory_key (NestedKey, optional) – entry holding per-transition trajectory ids. Defaults to None (auto-detection from
("collector", "traj_ids"),"traj_ids","episode"or the done/terminated/truncated flags).- Returns:
A list of matching trajectory views, ordered chronologically (oldest trajectory first; for multi-dimensional storages, grouped by batch coordinate).
The trajectory boundaries are computed from the stored (untransformed) data with the same machinery
SliceSampleruses, so samplers and queries always agree on where trajectories start and stop. This includes storages withndim > 1(e.g.LazyTensorStorage(..., ndim=2)holding[B, T]batches), whose trajectories are recovered per batch coordinate.Predicates built from
trajreport the keys they read viarequired_keys(); evaluation then only fetches those entries from the storage and only runs the transforms that can affect them. Matching trajectories are extracted in full with the complete transform chain applied, so predicates and results see the same values a sampler would produce. Opaque callables are evaluated against the fully transformed content.Note
Once the buffer has wrapped around (it is at capacity and older entries have been overwritten), the oldest trajectory may have lost its first transitions to overwriting and will appear truncated at the front. A trajectory written across the wrap point is followed through it and returned whole, in time order.
Examples
>>> from torchrl.data import traj >>> good_trajs = rb.query((traj.reward.sum() > 100) & (traj.length >= 50)) >>> observations = good_trajs[0].observation
- read_all_in_order(end: int | None = None) Any#
Read storage contents in physical order.
This is equivalent to
rb[:]whenendisNone.- Parameters:
end (int, optional) – Number of leading storage entries to read. Defaults to the entire storage slice.
- Returns:
A storage slice containing entries
[:end].
- register_load_hook(hook: Callable[[Any], Any])#
Registers a load hook for the storage.
Note
Hooks are currently not serialized when saving a replay buffer: they must be manually re-initialized every time the buffer is created.
- register_save_hook(hook: Callable[[Any], Any])#
Registers a save hook for the storage.
Note
Hooks are currently not serialized when saving a replay buffer: they must be manually re-initialized every time the buffer is created.
- sample(batch_size: int | None = None, return_info: bool = False, include_info: bool | None = None) TensorDictBase#
Samples a batch of data from the replay buffer.
Uses Sampler to sample indices, and retrieves them from Storage.
- Parameters:
batch_size (int, optional) – size of data to be collected. If none is provided, this method will sample a batch-size as indicated by the sampler.
return_info (bool) – whether to return info. If True, the result is a tuple (data, info). If False, the result is the data.
include_info (bool, optional) – deprecated alias for
return_info.
- Returns:
A tensordict containing a batch of data selected in the replay buffer. A tuple containing this tensordict and info if return_info flag is set to True.
- property sampler: Sampler#
The sampler of the replay buffer.
The sampler must be an instance of
Sampler.
- property service_backend: str#
The canonical deployment backend for this replay buffer.
- set_(key, value)#
Sets the value of a key across the entire replay buffer in-place.
- Parameters:
key (NestedKey) – the key to set.
value (torch.Tensor) – the value to write.
- Returns:
self
- set_at_(key, value, index)#
Sets the value of a key at specified indices in the replay buffer.
- Parameters:
key (NestedKey) – the key to set.
value (torch.Tensor) – the value to write.
index – the indices where to write the value.
- Returns:
self
- set_sampler(sampler: Sampler)#
Sets a new sampler in the replay buffer and returns the previous sampler.
- set_storage(storage: Storage, collate_fn: Callable | None = None)#
Sets a new storage in the replay buffer and returns the previous storage.
- Parameters:
storage (Storage) – the new storage for the buffer.
collate_fn (callable, optional) – if provided, the collate_fn is set to this value. Otherwise it is reset to a default value.
- shutdown(timeout: float | None = None) None#
Mark this direct replay-buffer owner as shut down.
- start() T#
Return this already-started direct replay buffer.
- stats() dict[str, int | float | bool]#
Returns a cheap, serializable snapshot of the buffer’s operational state.
The snapshot only contains scalar counters and gauges. It never includes the storage content, does not modify the buffer state and is safe to call concurrently with writes and samples. Cumulative counters such as
write_countare meant to be converted into rates by an external monitor such asLoggerMonitor.Calling this method on an uninitialized buffer does not trigger its initialization; an empty snapshot with
initialized=Falseis returned instead (capacityis still reported when the storage already advertises it).- Returns:
"size": current number of elements in the buffer (mirrorslen(buffer));"write_count": total number of items written throughaddandextend(0for writers that do not track writes, such asImmutableDatasetWriter);"prefetch_queue_size": number of pending prefetched batches;"initialized": whether the buffer components are initialized;"capacity": maximum number of elements the storage can hold (only present when the storage advertises amax_size);"utilization":size / capacity(only present alongsidecapacity).
Remote clients backed by the distributed transport report a subset of these entries (
sizeandwrite_count).- Return type:
A dictionary with the following entries
Examples
>>> import torch >>> from torchrl.data import LazyTensorStorage, ReplayBuffer >>> rb = ReplayBuffer(storage=LazyTensorStorage(10)) >>> rb.extend(torch.arange(5)) >>> snapshot = rb.stats() >>> print(snapshot["size"], snapshot["write_count"], snapshot["capacity"]) 5 5 10
- property storage: Storage#
The storage of the replay buffer.
The storage must be an instance of
Storage.
- property transform: Transform#
The transform of the replay buffer.
The transform must be an instance of
Transform.
- update_(input_dict_or_td, clone=False, *, keys_to_update=None)#
Updates the replay buffer in-place with the given dict or TensorDict.
- Parameters:
input_dict_or_td (dict or TensorDictBase) – the data to update with.
clone (bool, optional) – whether to clone the values before writing. Defaults to
False.keys_to_update (sequence of NestedKey, optional) – if provided, only these keys will be updated.
- Returns:
self
- update_if_present(*, index: Tensor, generation: Tensor, patch: Mapping[NestedKey, Tensor] | TensorDictBase, version_key: NestedKey | None = None, version: int | Tensor | None = None, require_newer: bool = False) ConditionalUpdateResult#
Conditionally updates stored records that are still live.
Replay slots are recycled by round-robin writers, so a physical index captured at sampling time can point to a different record by the time an asynchronous computation writes back. This method applies
patchonly to records whose(index, generation)pair still matches the writer’s current slot generation, skipping records whose slot was reused or emptied since the handle was captured. Skipped records are never modified.The whole patch is validated (key existence, shape and dtype) before any write happens; a validation failure leaves the storage untouched. Updating a record refreshes its content, not its identity: the same handle keeps working until the slot is rewritten by
add,extendorempty.Generation tracking is opt-in: the buffer must be constructed with a writer that tracks slot generations, e.g.
RoundRobinWriter(track_generations=True)(see ref_buffers_generations). Calling this method on a buffer whose writer does not track generations raises aRuntimeError.- Keyword Arguments:
index (torch.Tensor) – storage indices, as returned by
extend()or found in the sample under"index".generation (torch.Tensor) – slot generations captured with the indices, as found in the sample under
"index_generation".patch (mapping of NestedKey to torch.Tensor, or TensorDictBase) – the fields to overwrite for live records. Leading dimension must match the number of records addressed by
index.version_key (NestedKey, optional) – a stored per-record scalar field holding each record’s current version. When passed (together with
version), a generation-live record is only patched if the incoming version compares favorably against the stored one, and the accepted version is written intoversion_keyatomically with the patch.version_keymay not appear inpatch. Nested keys must be passed in tuple form (("nested", "version")); dotted strings are rejected. Defaults toNone(no version comparison).version (int or torch.Tensor, optional) – the incoming version, either a scalar (broadcast to every record) or a tensor with one entry per record. Must be passed together with
version_key.require_newer (bool, optional) – if
True, a record is only patched whenversion > stored; ifFalse, ties are accepted (version >= stored). When the same slot is addressed several times in one call, only the row carrying the highest incoming version is applied (the last such row on ties); the losing rows are reported inversion_rejected. Defaults toFalse.
- Returns:
A
ConditionalUpdateResultwhoseupdatedmask is aligned with the input index order, withupdated_countandstale_countconveniences. Whenversion_keyis passed, itsversion_rejectedmask marks generation-live records that were rejected by the version comparison (Noneotherwise).- Raises:
RuntimeError – if the storage does not support conditional updates (for example
ListStorage) or the writer does not track slot generations.KeyError – if a patch key (or
version_key) does not exist in the storage.ValueError – if a patch entry has an incompatible shape or dtype, if only one of
version_key/versionis passed, ifversion_keyappears inpatchor names a non-scalar field, or if it is a dotted string.
Examples
>>> import torch >>> from tensordict import TensorDict >>> from torchrl.data import ( ... LazyTensorStorage, ... TensorDictReplayBuffer, ... TensorDictRoundRobinWriter, ... ) >>> rb = TensorDictReplayBuffer( ... storage=LazyTensorStorage(10), ... writer=TensorDictRoundRobinWriter(track_generations=True), ... batch_size=4, ... ) >>> rb.extend(TensorDict({"obs": torch.zeros(10, 3)}, batch_size=[10])) >>> sample = rb.sample() >>> result = rb.update_if_present( ... index=sample["index"], ... generation=sample["index_generation"], ... patch={"obs": torch.ones(4, 3)}, ... ) >>> print(result.updated_count, result.stale_count) 4 0
With a version comparison, outdated asynchronous writers lose deterministically:
>>> rb = TensorDictReplayBuffer( ... storage=LazyTensorStorage(10), ... writer=TensorDictRoundRobinWriter(track_generations=True), ... batch_size=4, ... ) >>> rb.extend( ... TensorDict( ... { ... "obs": torch.zeros(10, 3), ... "v": torch.full((10,), 5, dtype=torch.int64), ... }, ... batch_size=[10], ... ) ... ) >>> sample = rb.sample() >>> result = rb.update_if_present( ... index=sample["index"], ... generation=sample["index_generation"], ... patch={"obs": torch.ones(4, 3)}, ... version_key="v", ... version=4, ... require_newer=True, ... ) >>> print(result.updated_count, result.version_rejected_count) 0 4
- write_all(data: Any, end: int | None = None) None#
Write data back to storage in physical order.
This is equivalent to
rb[:end] = data. IfendisNone,enddefaults todata.shape[0]for tensor collections andlen(data)otherwise. Ifdataspans the full storage, this is equivalent torb[:] = data.- Parameters:
data – Data to write to storage.
end (int, optional) – Number of leading storage entries to update. Defaults to
data.shape[0]for tensor collections andlen(data)otherwise.
- property write_count: int#
The total number of items written so far in the buffer through add and extend.