#
Model Utilities

##
get_act_offloading_ctx_manager

####
trl.models.get_act_offloading_ctx_manager

< source >

( model: Module use_pin_memory: bool = True use_streams: bool = True min_offload_size: int = 1024 max_fwd_stash_size: int = 5 warn_if_no_head: bool = True ) →
`contextlib.ContextDecorator`

Parameters

- model (`nn.Module`) — Model to wrap with the activation offloading context manager.
- use_pin_memory (`bool`, optional, defaults to `True`) — Whether to offloaded Tensor will be placed in pinned memory on the CPU. Pinned memory allows the Tensor to be moved back onto GPU more quickly but is a limited resource.
- use_streams (`bool`, optional, defaults to `True`) — Whether to use streams for performance optimization where the communications get overlapped with the computation. Requires a torch build after torch-2.5.0.
- min_offload_size (`int`, optional, defaults to `1024`) — Minimum number of bytes a Tensor must be in order to qualify for offloading. If the tensor is too small, we do not want to waste bandwidth and resources moving it to CPU and back.
- max_fwd_stash_size (`int`, optional, defaults to `5`) — Maximum size of the forward stash, or the maximum number of consecutive activations to keep alive during the forward pass. This number must be at least 1. Keeping alive more activations will potentially allow more overlap between the communication and compute streams at the cost of increasing memory usage. Keeping alive fewer activations will conserve memory, but may cause poor overlap between the streams, increasing runtime.
- warn_if_no_head (`bool`, optional, defaults to `True`) — Whether to warn if no output head is detected. If set to `False`, no warning will be raised if no output head is detected.

Returns

`contextlib.ContextDecorator`

Activation offloading context manager for the model.

Returns the activation offloading context manager for the model. All but the last output Linear in every step will be offloaded.

If activation offloading is enabled, we return the OffloadActivations context manager. If activation offloading is disabled, we return a NoOpManager context manager.

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