Error on worker 2

[georgeblck]

I am trying to run the MNIST example and am getting the following error when trying to train the model.

On worker 2:
The Python TensorFlow package could not be imported. You must install Python TensorFlow before using this package.
 in init at /home/user/.julia/v0.5/TensorFlow/src/py.jl:12
 in #12 at /home/user/.julia/v0.5/TensorFlow/src/TensorFlow.jl:137
 in #649 at ./multi.jl:1428
 in run_work_thunk at ./multi.jl:1001
 in run_work_thunk at ./multi.jl:1010 [inlined]
 in #617 at ./event.jl:68
 in #remotecall_wait#631(::Array{Any,1}, ::Function, ::Function, ::Base.Worker) at multi.jl:1095
 in remotecall_wait(::Function, ::Base.Worker) at multi.jl:1086
 in #remotecall_wait#634(::Array{Any,1}, ::Function, ::Function, ::Int64) at multi.jl:1105
 in remotecall_wait(::Function, ::Int64) at multi.jl:1105
 in eval(::Module, ::Any) at boot.jl:234
 in load_python_process() at TensorFlow.jl:131
 in gradients(::TensorFlow.Tensor, ::Array{Any,1}) at core.jl:1211
 in compute_gradients(::TensorFlow.train.GradientDescentOptimizer, ::TensorFlow.Tensor, ::Void) at train.jl:48
 in #minimize#1(::Void, ::Void, ::String, ::Function, ::TensorFlow.train.GradientDescentOptimizer, ::TensorFlow.Tensor) at train.jl:40
 in #train!#11(::Int64, ::Float64, ::Flux.TF.##13#15, ::TensorFlow.train.GradientDescentOptimizer, ::Function, ::Flux.TF.Model, ::Array{Tuple{Array{Float64,1},Array{Int64,1}},1}, ::Array{Tuple{Array{Float64,1},Array{Int64,1}},1}) at model.jl:78
 in (::Flux.#kw##train!)(::Array{Any,1}, ::Flux.#train!, ::Flux.TF.Model, ::Array{Tuple{Array{Float64,1},Array{Int64,1}},1}, ::Array{Tuple{Array{Float64,1},Array{Int64,1}},1}) at <missing>:0
 in include_string(::String, ::String) at loading.jl:441
 in include_string(::String, ::String, ::Int64) at eval.jl:28
 in include_string(::Module, ::String, ::String, ::Int64, ::Vararg{Int64,N}) at eval.jl:32
 in (::Atom.##53#56{String,Int64,String})() at eval.jl:40
 in withpath(::Atom.##53#56{String,Int64,String}, ::String) at utils.jl:30
 in withpath(::Function, ::String) at eval.jl:46
 in macro expansion at eval.jl:57 [inlined]
 in (::Atom.##52#55{Dict{String,Any}})() at task.jl:60

[MikeInnes]

This error is coming from TensorFlow.jl, you need to do pip install tensorflow so your local Python can find it. If you get stuck with that you could try asking here.

[georgeblck]

I would've thought that as well, but the On worker 2- line got me thinking that Flux/TensorFlow was trying to run the code on more than one CPU.
I'll try the pip install tensorflow now!

[MikeInnes]

It's weird, but TensorFlow.jl actually boots a background Julia process and uses that to communicate with tensorflow in Python, hence the error.

[MikeInnes]

Hopefully you got this sorted – if not I recommend MXNet which has a pretty robust install process.