JaxPM/tests/test_distributed_pm.py
2025-02-28 14:03:33 +01:00

400 lines
15 KiB
Python

from conftest import initialize_distributed
initialize_distributed() # ignore : E402
from functools import partial # noqa : E402
import jax # noqa : E402
import jax.numpy as jnp # noqa : E402
import jax_cosmo as jc # noqa : E402
import pytest # noqa : E402
from diffrax import SaveAt # noqa : E402
from diffrax import Dopri5, ODETerm, PIDController, diffeqsolve
from helpers import MSE # noqa : E402
from jax import lax # noqa : E402
from jax.experimental.multihost_utils import process_allgather # noqa : E402
from jax.sharding import NamedSharding
from jax.sharding import PartitionSpec as P # noqa : E402
from jaxdecomp import get_fft_output_sharding
from jaxpm.distributed import uniform_particles # noqa : E402
from jaxpm.distributed import fft3d, ifft3d
from jaxpm.painting import cic_paint, cic_paint_dx # noqa : E402
from jaxpm.pm import lpt, make_diffrax_ode, pm_forces # noqa : E402
_TOLERANCE = 1e-1 # 🙃🙃
pdims = [(1, 8), (8, 1), (4, 2), (2, 4)]
@pytest.mark.distributed
@pytest.mark.parametrize("order", [1, 2])
@pytest.mark.parametrize("pdims", pdims)
@pytest.mark.parametrize("absolute_painting", [True, False])
def test_distrubted_pm(simulation_config, initial_conditions, cosmo, order,
pdims, absolute_painting):
if absolute_painting:
pytest.skip("Absolute painting is not recommended in distributed mode")
painting_str = "absolute" if absolute_painting else "relative"
print("=" * 50)
print(f"Running with {painting_str} painting and pdims {pdims} ...")
mesh_shape, box_shape = simulation_config
# SINGLE DEVICE RUN
cosmo._workspace = {}
if absolute_painting:
particles = uniform_particles(mesh_shape)
# Initial displacement
dx, p, _ = lpt(cosmo,
initial_conditions,
particles,
a=0.1,
order=order)
ode_fn = ODETerm(make_diffrax_ode(mesh_shape))
y0 = jnp.stack([particles + dx, p])
else:
dx, p, _ = lpt(cosmo, initial_conditions, a=0.1, order=order)
ode_fn = ODETerm(make_diffrax_ode(mesh_shape,
paint_absolute_pos=False))
y0 = jnp.stack([dx, p])
solver = Dopri5()
controller = PIDController(rtol=1e-8,
atol=1e-8,
pcoeff=0.4,
icoeff=1,
dcoeff=0)
saveat = SaveAt(t1=True)
solutions = diffeqsolve(ode_fn,
solver,
t0=0.1,
t1=1.0,
dt0=None,
y0=y0,
args=cosmo,
stepsize_controller=controller,
saveat=saveat)
if absolute_painting:
single_device_final_field = cic_paint(jnp.zeros(shape=mesh_shape),
solutions.ys[-1, 0])
else:
single_device_final_field = cic_paint_dx(solutions.ys[-1, 0])
print("Done with single device run")
# MULTI DEVICE RUN
mesh = jax.make_mesh(pdims, ('x', 'y'))
sharding = NamedSharding(mesh, P('x', 'y'))
halo_size = mesh_shape[0] // 2
initial_conditions = lax.with_sharding_constraint(initial_conditions,
sharding)
print(f"sharded initial conditions {initial_conditions.sharding}")
cosmo._workspace = {}
if absolute_painting:
particles = uniform_particles(mesh_shape, sharding=sharding)
# Initial displacement
dx, p, _ = lpt(cosmo,
initial_conditions,
particles,
a=0.1,
order=order,
halo_size=halo_size,
sharding=sharding)
ode_fn = ODETerm(
make_diffrax_ode(mesh_shape,
halo_size=halo_size,
sharding=sharding))
y0 = jnp.stack([particles + dx, p])
else:
dx, p, _ = lpt(cosmo,
initial_conditions,
a=0.1,
order=order,
halo_size=halo_size,
sharding=sharding)
ode_fn = ODETerm(
make_diffrax_ode(mesh_shape,
paint_absolute_pos=False,
halo_size=halo_size,
sharding=sharding))
y0 = jnp.stack([dx, p])
solver = Dopri5()
controller = PIDController(rtol=1e-8,
atol=1e-8,
pcoeff=0.4,
icoeff=1,
dcoeff=0)
saveat = SaveAt(t1=True)
solutions = diffeqsolve(ode_fn,
solver,
t0=0.1,
t1=1.0,
dt0=None,
y0=y0,
args=cosmo,
stepsize_controller=controller,
saveat=saveat)
final_field = solutions.ys[-1, 0]
print(f"Final field sharding is {final_field.sharding}")
assert final_field.sharding.is_equivalent_to(sharding , ndim=3) \
, f"Final field sharding is not correct .. should be {sharding} it is instead {final_field.sharding}"
if absolute_painting:
multi_device_final_field = cic_paint(jnp.zeros(shape=mesh_shape),
final_field,
halo_size=halo_size,
sharding=sharding)
else:
multi_device_final_field = cic_paint_dx(final_field,
halo_size=halo_size,
sharding=sharding)
multi_device_final_field = process_allgather(multi_device_final_field,
tiled=True)
mse = MSE(single_device_final_field, multi_device_final_field)
print(f"MSE is {mse}")
assert mse < _TOLERANCE
@pytest.mark.distributed
@pytest.mark.parametrize("order", [1, 2])
@pytest.mark.parametrize("pdims", pdims)
def test_distrubted_gradients(simulation_config, initial_conditions, cosmo,
order, nbody_from_lpt1, nbody_from_lpt2, pdims):
mesh_shape, box_shape = simulation_config
# SINGLE DEVICE RUN
cosmo._workspace = {}
mesh = jax.make_mesh(pdims, ('x', 'y'))
sharding = NamedSharding(mesh, P('x', 'y'))
halo_size = mesh_shape[0] // 2
initial_conditions = lax.with_sharding_constraint(initial_conditions,
sharding)
print(f"sharded initial conditions {initial_conditions.sharding}")
cosmo._workspace = {}
@jax.jit
def forward_model(initial_conditions, cosmo):
dx, p, _ = lpt(cosmo,
initial_conditions,
a=0.1,
order=order,
halo_size=halo_size,
sharding=sharding)
ode_fn = ODETerm(
make_diffrax_ode(mesh_shape,
paint_absolute_pos=False,
halo_size=halo_size,
sharding=sharding))
y0 = jax.tree.map(lambda dx, p: jnp.stack([dx, p]), dx, p)
solver = Dopri5()
controller = PIDController(rtol=1e-8,
atol=1e-8,
pcoeff=0.4,
icoeff=1,
dcoeff=0)
saveat = SaveAt(t1=True)
solutions = diffeqsolve(ode_fn,
solver,
t0=0.1,
t1=1.0,
dt0=None,
y0=y0,
args=cosmo,
stepsize_controller=controller,
saveat=saveat)
multi_device_final_field = cic_paint_dx(solutions.ys[-1, 0],
halo_size=halo_size,
sharding=sharding)
return multi_device_final_field
@jax.jit
def model(initial_conditions, cosmo):
final_field = forward_model(initial_conditions, cosmo)
return MSE(final_field,
nbody_from_lpt1 if order == 1 else nbody_from_lpt2)
obs_val = model(initial_conditions, cosmo)
shifted_initial_conditions = initial_conditions + jax.random.normal(
jax.random.key(42), initial_conditions.shape) * 5
good_grads = jax.grad(model)(initial_conditions, cosmo)
off_grads = jax.grad(model)(shifted_initial_conditions, cosmo)
assert good_grads.sharding.is_equivalent_to(initial_conditions.sharding,
ndim=3)
assert off_grads.sharding.is_equivalent_to(initial_conditions.sharding,
ndim=3)
@pytest.mark.distributed
@pytest.mark.parametrize("pdims", pdims)
def test_fwd_rev_gradients(cosmo, pdims):
mesh_shape, box_shape = (8, 8, 8), (20.0, 20.0, 20.0)
cosmo._workspace = {}
mesh = jax.make_mesh(pdims, ('x', 'y'))
sharding = NamedSharding(mesh, P('x', 'y'))
halo_size = mesh_shape[0] // 2
initial_conditions = jax.random.normal(jax.random.PRNGKey(42), mesh_shape)
initial_conditions = lax.with_sharding_constraint(initial_conditions,
sharding)
print(f"sharded initial conditions {initial_conditions.sharding}")
cosmo._workspace = {}
@partial(jax.jit, static_argnums=(2, 3, 4))
def compute_forces(initial_conditions,
cosmo,
a=0.5,
halo_size=0,
sharding=None):
paint_absolute_pos = False
particles = jnp.zeros_like(initial_conditions,
shape=(*initial_conditions.shape, 3))
a = jnp.atleast_1d(a)
E = jnp.sqrt(jc.background.Esqr(cosmo, a))
initial_conditions = jax.lax.with_sharding_constraint(
initial_conditions, sharding)
delta_k = fft3d(initial_conditions)
out_sharding = get_fft_output_sharding(sharding)
delta_k = jax.lax.with_sharding_constraint(delta_k, out_sharding)
initial_force = pm_forces(particles,
delta=delta_k,
paint_absolute_pos=paint_absolute_pos,
halo_size=halo_size,
sharding=sharding)
return initial_force[..., 0]
forces = compute_forces(initial_conditions,
cosmo,
halo_size=halo_size,
sharding=sharding)
back_gradient = jax.jacrev(compute_forces)(initial_conditions,
cosmo,
halo_size=halo_size,
sharding=sharding)
fwd_gradient = jax.jacfwd(compute_forces)(initial_conditions,
cosmo,
halo_size=halo_size,
sharding=sharding)
print(f"Forces sharding is {forces.sharding}")
print(f"Backward gradient sharding is {back_gradient.sharding}")
print(f"Forward gradient sharding is {fwd_gradient.sharding}")
assert forces.sharding.is_equivalent_to(initial_conditions.sharding,
ndim=3)
assert back_gradient[0, 0, 0, ...].sharding.is_equivalent_to(
initial_conditions.sharding, ndim=3)
assert fwd_gradient.sharding.is_equivalent_to(initial_conditions.sharding,
ndim=3)
@pytest.mark.distributed
@pytest.mark.parametrize("pdims", pdims)
def test_vmap(cosmo, pdims):
mesh_shape, box_shape = (8, 8, 8), (20.0, 20.0, 20.0)
cosmo._workspace = {}
mesh = jax.make_mesh(pdims, ('x', 'y'))
sharding = NamedSharding(mesh, P('x', 'y'))
halo_size = mesh_shape[0] // 2
single_dev_initial_conditions = jax.random.normal(jax.random.PRNGKey(42),
mesh_shape)
initial_conditions = lax.with_sharding_constraint(
single_dev_initial_conditions, sharding)
single_ics = jnp.stack([
single_dev_initial_conditions, single_dev_initial_conditions,
single_dev_initial_conditions
])
sharded_ics = jnp.stack(
[initial_conditions, initial_conditions, initial_conditions])
print(f"unsharded initial conditions batch {single_ics.sharding}")
print(f"sharded initial conditions batch {sharded_ics.sharding}")
cosmo._workspace = {}
@partial(jax.jit, static_argnums=(2, 3, 4))
def compute_forces(initial_conditions,
cosmo,
a=0.5,
halo_size=0,
sharding=None):
paint_absolute_pos = False
particles = jnp.zeros_like(initial_conditions,
shape=(*initial_conditions.shape, 3))
a = jnp.atleast_1d(a)
E = jnp.sqrt(jc.background.Esqr(cosmo, a))
initial_conditions = jax.lax.with_sharding_constraint(
initial_conditions, sharding)
delta_k = fft3d(initial_conditions)
out_sharding = get_fft_output_sharding(sharding)
delta_k = jax.lax.with_sharding_constraint(delta_k, out_sharding)
initial_force = pm_forces(particles,
delta=delta_k,
paint_absolute_pos=paint_absolute_pos,
halo_size=halo_size,
sharding=sharding)
return initial_force[..., 0]
def fn(ic):
return compute_forces(ic,
cosmo,
halo_size=halo_size,
sharding=sharding)
v_compute_forces = jax.vmap(fn)
print(f"single_ics shape {single_ics.shape}")
print(f"sharded_ics shape {sharded_ics.shape}")
single_dev_forces = v_compute_forces(single_ics)
sharded_forces = v_compute_forces(sharded_ics)
assert single_dev_forces.ndim == 4
assert sharded_forces.ndim == 4
print(f"Sharded forces {sharded_forces.sharding}")
assert sharded_forces[0].sharding.is_equivalent_to(
initial_conditions.sharding, ndim=3)
assert sharded_forces.sharding.spec[0] == None