Increasing Total Integer Workspace with Snopt - Exit code 83

Drake Version: v1.40, from pip

Platform: Macbook M4 Pro

I am attempting to use the Snopt via MathematicalProgram and am running into an exit condition of 83, which corresponds with exceeding the storage limit of the integer workspace. I tried setting the Total integer workspace option, but there seems to be no effect for any value for this option.

Here is my abbreviated script:

...
prog = MathematicalProgram()
Z = prog.NewContinuousVariables(N, nz)
U = prog.NewContinuousVariables(N-1, 2)

prog.AddLinearConstraint(Z[0] - z0, np.zeros(nz), np.zeros(nz))

for i in range(N-1):
    z_k = z0 if i==0 else Z[i]
    s = Z[i+1, nq:]
    x_k = z_k[:nq]
    v_next = s[:nq]
    u = np.concatenate([U[i], np.zeros(nq-2)])
    for row in dynamics_residual(z_k, s, u, params):
        prog.AddQuadraticConstraint(row, 0, 0, hessian_type=QuadraticConstraint.HessianType.kIndefinite)

    prog.AddLinearConstraint(Z[i+1, :nq] - (x_k + dt*v_next), np.zeros(nq), np.zeros(nq))

for i, hand_pos in enumerate(hand_path[:-1]):
    prog.AddLinearConstraint(hand_pos - Z[i, :2], np.zeros(2), np.zeros(2))


solver = SnoptSolver()

filename = "/tmp/debug.txt"
solver_options = SolverOptions()
solver_options.SetOption(CommonSolverOption.kPrintFileName, filename)

solver_options.SetOption(SnoptSolver.id(), "Total integer workspace", 1e6)
solver_options.SetOption(SnoptSolver.id(), "Total real workspace", 4e6)
solver_options.SetOption(SnoptSolver.id(), "User integer workspace", 1e6)
solver_options.SetOption(SnoptSolver.id(), "User real workspace", 4e6)
solver_options.SetOption(SnoptSolver.id(), "Major print level", 5)

result = solver.Solve(prog, solver_options=solver_options)
...

From Snopt output:

 lu1fac  error...  insufficient storage

 Increase  lena  from    166326  to at least    243971

                                Current    Recommended
 Total integer workspace         632738         788028
 Total real    workspace        2850909        2928554
1
 
 SNOPTA EXIT  80 -- insufficient storage allocated
 SNOPTA INFO  83 -- not enough integer storage

My overall device memory is not being filled so it seems likely that this is an issue with the option setting.

Seems to be a similar error as with:

Am I setting the integer workspace option incorrectly or is there a different parameter that should be set?

Thanks!

Solution

As of v1.41.0, Drake sets the integer workspace to be exactly what's calculated by snmema:

https://github.com/RobotLocomotion/drake/blob/bd7834fbdacae94b33385a54caa0e66871f8ca85/solvers/snopt_solver.cc#L1349-L1357

  Snopt::snmema(&snopt_status, nF, nx, lenA, lenG, &miniw, &minrw, storage.iw(),
                storage.leniw(), storage.rw(), storage.lenrw());
  if (miniw > storage.leniw()) {
    storage.resize_iw(miniw);
    const std::string option = "Total int workspace";
    Snopt::snseti(option.c_str(), option.length(), storage.leniw(), &errors,
                  storage.iw(), storage.leniw(), storage.rw(), storage.lenrw());

This means that the any user-provided value for "Total integer workspace" will be ignored.

Reading SNOPT the manual for snMemA, other options like "Superbasics limit" can affect what snMemA reports so possibly setting those option(s) could be work-around.

Ideally, Drake would notice that the user has set a larger workspace in the options, and use that setting instead of asking snmema. See https://github.com/RobotLocomotion/drake/issues/23032.