Tuners
A tuner (or adapter) is a module that can be plugged into a torch.nn.Module
. BaseTuner
base class for other tuners and provides shared methods and attributes for preparing an adapter configuration and replacing a target module with the adapter module. BaseTunerLayer
is a base class for adapter layers. It offers methods and attributes for managing adapters such as activating and disabling adapters.
BaseTuner
class peft.tuners.tuners_utils.BaseTuner
< source >( model peft_config: Union[PeftConfig, dict[str, PeftConfig]] adapter_name: str )
Parameters
- model (
torch.nn.Module
) — The model to which the adapter tuner layers will be attached. - forward (
Callable
) — The forward method of the model. - peft_config (
Union[
PeftConfig, dict[str, PeftConfig]]
) — The adapter configuration object, it should be a dictionary ofstr
toPeftConfig
objects. One can also pass a PeftConfig object and a new adapter will be created with the default nameadapter
or create a new dictionary with a keyadapter_name
and a value of that peft config. - config (
dict[str, Any]
) — The model configuration object, it should be a dictionary ofstr
toAny
objects. - targeted_module_names (
list[str]
) — The list of module names that were actually adapted. Can be useful to inspect if you want to quickly double-check that theconfig.target_modules
where specified correctly.
A base tuner model that provides the common methods and attributes for all tuners that are injectable into a torch.nn.Module
For adding a new Tuner class, one needs to overwrite the following methods:
- _prepare_adapter_config:
A private method to eventually prepare the adapter config, for example in case the field
target_modules
is missing. - _create_and_replace: A private method to create and replace the target module with the adapter module.
- _check_target_module_exists: A private helper method to check if the passed module’s key name matches any of the target modules in the adapter_config.
The easiest is to check what is done in the peft.tuners.lora.LoraModel
class.
Disable all adapters in-place.
Enable all adapters in-place
inject_adapter
< source >( model: nn.Module adapter_name: str )
Creates adapter layers and replaces the target modules with the adapter layers. This method is called under the
hood by peft.mapping.get_peft_model
if a non-prompt tuning adapter class is passed.
The corresponding PEFT config is directly retrieved from the peft_config
attribute of the BaseTuner class.
merge_adapter
< source >( adapter_names: Optional[list[str]] = None )
Parameters
- safe_merge (
bool
, optional) — IfTrue
, the merge operation will be performed in a copy of the original weights and check for NaNs before merging the weights. This is useful if you want to check if the merge operation will produce NaNs. Defaults toFalse
. - adapter_names (
list[str]
, optional) — The list of adapter names that should be merged. IfNone
, all active adapters will be merged. Defaults toNone
.
This method merges the adapter layers into the base model.
Merging adapters can lead to a speed up of the forward pass. A copy of the adapter weights is still kept in
memory, which is required to unmerge the adapters. In order to merge the adapter weights without keeping them
in memory, please call merge_and_unload
.
This method unmerges all merged adapter layers from the base model.
BaseTunerLayer
class peft.tuners.tuners_utils.BaseTunerLayer
< source >( )
A tuner layer mixin that provides the common methods and attributes for all tuners.
delete_adapter
< source >( adapter_name: str )
Delete an adapter from the layer
This should be called on all adapter layers, or else we will get an inconsistent state.
This method will also set a new active adapter if the deleted adapter was an active adapter. It is important that the new adapter is chosen in a deterministic way, so that the same adapter is chosen on all layers.
enable_adapters
< source >( enabled: bool )
Toggle the enabling and disabling of adapters
Takes care of setting the requires_grad flag for the adapter weights.
(Recursively) get the base_layer.
This is necessary for the case that the tuner layer wraps another tuner layer.
set_adapter
< source >( adapter_names: str | list[str] )
Set the active adapter(s).
Additionally, this function will set the specified adapters to trainable (i.e., requires_grad=True). If this is not desired, use the following code.