Flux.jl/docs/src/saving.md

Saving and Loading Models

You may wish to save models so that they can be loaded and run in a later session. The easiest way to do this is via BSON.jl.

Save a model:

julia> using Flux

julia> model = Chain(Dense(10,5,relu),Dense(5,2),softmax)
Chain(Dense(10, 5, NNlib.relu), Dense(5, 2), NNlib.softmax)

julia> using BSON: @save

julia> @save "mymodel.bson" model

Load it again:

julia> using Flux

julia> using BSON: @load

julia> @load "mymodel.bson" model

julia> model
Chain(Dense(10, 5, NNlib.relu), Dense(5, 2), NNlib.softmax)

Models are just normal Julia structs, so it's fine to use any Julia storage format for this purpose. BSON.jl is particularly well supported and most likely to be forwards compatible (that is, models saved now will load in future versions of Flux).

!!! note

If a saved model's weights are stored on the GPU, the model will not load
later on if there is no GPU support available. It's best to [move your model
to the CPU](gpu.md) with `cpu(model)` before saving it.

Saving Model Weights

In some cases it may be useful to save only the model parameters themselves, and rebuild the model architecture in your code. You can use params(model) to get model parameters. You can also use data.(params) to remove tracking.

julia> using Flux

julia> model = Chain(Dense(10,5,relu),Dense(5,2),softmax)
Chain(Dense(10, 5, NNlib.relu), Dense(5, 2), NNlib.softmax)

julia> weights = Tracker.data.(params(model));

julia> using BSON: @save

julia> @save "mymodel.bson" weights

You can easily load parameters back into a model with Flux.loadparams!.

julia> using Flux

julia> using BSON: @load

julia> model = Chain(Dense(10,5,relu),Dense(5,2),softmax)
Chain(Dense(10, 5, NNlib.relu), Dense(5, 2), NNlib.softmax)

julia> @load "mymodel.bson" weights

julia> Flux.loadparams!(model, weights)

The new model we created will now be identical to the one we saved parameters for.