Is it normal for v10 to create System 10x bigger than v9.xx #3694
Description
I am testing the breaking v10 with my 3D multi-body MTK (ODE)System.
Code required minimal adjustment and, eventually, leads to the same results. So far so good.
However, I noticed the mtkcompile() (formerly structural_simplify()) runs a little faster (20s -> 14s), but the ODEProblem(sys, op, tspan) creation (formerly ODEProblem(sys, u0, tspan, p0)) takes massively longer (120s -> 3000+s) and creates a ~10x larger problem (120M -> 1.6G allocations).
I have reduced the test system right down to a very basic 2-bodies connected with an elastic spring (f=0 for delta_l<0), so not exactly complex.
ODEProblem with uType Vector{Float64} and tType Float64. In-place: true
Initialization status: FULLY_DETERMINED
Non-trivial mass matrix: false
timespan: (0.0, 1.0)
u0: 24-element Vector{Float64}:
...Is that expected behaviour for v10 as result of the new System definition?