Parameter estimation of an ODE in Julia is slower than in R

[ChrisRackauckas]

That is still allocating in the inner loop of the ODE solve because of the matmul.

I suggest looking at the following resources:

https://diffeq.sciml.ai/stable/tutorials/faster_ode_example/

Optimizing Serial Code in Julia 1: Memory Models, Mutation, and Vectorization

Code Profiling and Optimization (in Julia)