Hi,
I am trying to use ForwardDiff to compute the jacobian of a system of equations that I anticipate will be very large. Below is a very simplified working code that illustrate what I am trying to do.
When I run the code below I get the following as output from @time
:
20.089338 seconds (128.02 k allocations: 46.572 GiB, 4.09% gc time)
Since I am new in Julia, it is likely that I am doing something wrong. Could someone help with the following questions:

Would you expect that
ForwardDiff.jacobian
takes 20s to for the case of 50K equations ? 
Could you let me know if there is anything that I could do to optimize the code below ?
Thanks in advance for the help.
using ForwardDiff
using ForwardDiff: Chunk
function ResidualEquations( X::AbstractArray )
1*X
end
p0 = rand(50000)
f(x) = ResidualEquations(x)
println("\n \t ... Creating Config ... ")
jconfig = ForwardDiff.JacobianConfig( f , p0, Chunk{2}())
println("\n \t ... Evaluating jacobian ... ")
@time jac = ForwardDiff.jacobian( f, p0, jconfig )::Array{Float64,2}