QNDF slowed down while rationalizing floats #2921
Description
using OrdinaryDiffEqBDF, ProfileCanvas
f(du, u, p, t) = du .= 0.0
prob = ODEProblem(f, ones(10), (0.0, 1.0))
@profview sol = solve(prob, QNDF(); adaptive = false, dt = 1e-6, save_everystep = false)
As highlighted in the flamegraph, this spends a lot of time rationalizing a float here:
This is not supposed to happen? It does not happen with FBDF.