Performance of main (2024-08-17) is worse compared to v8.6.0

[adtzlr]

The benchmark runs faster on v8.6.0 compared to main for the largest mesh. Try to figure out the reason(s) before creating a new release.

[adtzlr]

main:

v8.6.0:

[adtzlr]

Try to use a minimal benchmark.

import felupe as fem

mesh = fem.Cube(n=21)
region = fem.RegionHexahedron(mesh)
field = fem.FieldContainer([fem.Field(region, dim=3)])
umat = fem.NeoHooke(mu=1, bulk=2)
solid = fem.SolidBody(umat=umat, field=field)

with

%timeit solid.assemble.matrix()

This gives 2.5 s (main) vs. 900 ms!!

[adtzlr]

Let's use a more low-level benchmark.

import felupe as fem

mesh = fem.Cube(n=21)
region = fem.RegionHexahedron(mesh)
field = fem.FieldContainer([fem.Field(region, dim=3)])
umat = fem.NeoHooke(mu=1, bulk=2)

fun = umat.hessian(field.extract())
form = fem.IntegralForm(fun, field, region.dV, u=field)

values = form.integrate()
matrix = form.assemble(values)

# %timeit form.integrate()
# %timeit form.assemble(values)

1.8 s (main) vs. 380 ms

Something has changed in assembly.IntegralFormCartesian. The dhdX-arrays of the region are not C-contiguous anymore. That slows down the einsum-evaluation.

form.u[0].region.dhdX.flags
Out[25]: 
  C_CONTIGUOUS : False
  F_CONTIGUOUS : False
  OWNDATA : True
  WRITEABLE : True
  ALIGNED : True
  WRITEBACKIFCOPY : False