[self-tests] pyamg/tests/test_graph.py::TestGraph::test_bellman_ford hangs on i586 platform

[stanislavlevin]

pyamg/tests/test_graph.py::TestGraph::test_bellman_ford hangs on i586 machine.

Minimal reproducer based on hanging test:

from scipy import sparse
import numpy as np

from pyamg.gallery import poisson
from pyamg.graph import bellman_ford


def canonical_graph(G):
    G = sparse.coo_matrix(G)

    mask = G.row != G.col
    G.row = G.row[mask]
    G.col = G.col[mask]
    G.data = G.data[mask]
    G.data[:] = 1
    return G


graph = canonical_graph(poisson((5, 5)))
graph.data = np.random.rand(graph.nnz) 
N = graph.shape[0] 

n_seeds = int(N/20)
seeds = np.random.permutation(N)[:n_seeds]
bellman_ford(graph, seeds)

Versions (checked on 4.2.3 and current main):

pytest version: 7.1.2
scipy  version: 1.6.1
numpy  version: 1.22.1
pyamg  version: 4.2.3.post1.dev11+gf9b2805

[lukeolson]

@stanislavlevin closing for now. If it still hangs on an updated scipy/numpy/pyamg version then we can reopen.

[matoro]

Hi, can I ask that this be reopened? This reproduces on i686 with the following versions:

pytest version: 7.4.3
scipy  version: 1.11.3
numpy  version: 1.26.1
pyamg  version: 5.0.1

[lukeolson]

@matoro thanks for reporting.

I'm still unable to reproduce and the tests pass:

python -c "import pyamg; pyamg.test()"
Python version: 3.11.6 (main, Oct  8 2023, 05:06:43) [GCC 13.2.0]
pytest version: 7.4.3
scipy  version: 1.11.3
numpy  version: 1.26.1
pyamg  version: 5.0.1

This is sounding like a memory leak. I'll check valgrind as a start.

[matoro]

@matoro thanks for reporting.

I'm still unable to reproduce and the tests pass:

python -c "import pyamg; pyamg.test()"
Python version: 3.11.6 (main, Oct  8 2023, 05:06:43) [GCC 13.2.0]
pytest version: 7.4.3
scipy  version: 1.11.3
numpy  version: 1.26.1
pyamg  version: 5.0.1

This is sounding like a memory leak. I'll check valgrind as a start.

I don't see any meaningful memory usage change during the hang. Just spins one CPU indefinitely. You are running 32-bit right?

# python3 -c "import platform; print(platform.architecture())"
('32bit', 'ELF')