Base.Meta.ParseError("invalid operator \"--\"") when multiprocessing

[atthom]

Hello,

I'm using your package with a huge list of expression.
Basically, I'm doing this:

res = map(exp -> (exp, rcall(exp)), res)

It run correctly but it is taking forever and my CPU is barely used.

So I wanted to speed things up with multiprocessing. I tried with pmap, @threads, @spawn and @distributed and starting with julia -p 6 in deed.

Most of the time I get this error :

ERROR: LoadError: On worker 2:
Base.Meta.ParseError("invalid operator \"--\"")

Or no error but no increase in speed (and CPU < 10%).

Moreover, I have this error without doing any multiprocessing.
With the same code I can crash if I start julia ./script.jl
but I don't crash inside the REPL julia> include("GenerateFormula4.jl")
I'm using Windows 10.

I'm still new to Julia so I'm not sure what could cause the problem.

[chakravala]

The Reduce.jl package is not currently designed to handle multiprocessing, since communication is based on a single pipe communicating with another process. I've thought about specifically adding some feature to open multiple separate callable instances of the reduce process, but never tried it yet.

[atthom]

Thank you for your prompt reply.
I'll be glad to try this new feature.
Meanwhile I will try to find a workaround.

[chakravala]

Reduce.jl is fairly quick and responsive, but is limited in performance by the character stream interface. It's possible to create a faster interface for Reduce, but it would not be a simple task.

Note that you can also send multiple commands to Reduce at once (like an expression block).