adds mpi tools

This commit is contained in:
EiffL 2022-10-22 08:30:43 -04:00
parent 2db7c43ab8
commit 3c1abbafcd
2 changed files with 222 additions and 76 deletions

111
jaxpm/ops.py Normal file
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@ -0,0 +1,111 @@
# Module for custom ops, typically mpi4jax
import jax
import jax.numpy as jnp
import mpi4jax
def fft3d(arr, token=None, comms=None):
""" Computes forward FFT, note that the output is transposed
"""
if comms is not None:
shape = list(arr.shape)
nx = comms[0].Get_size()
ny = comms[1].Get_size()
# First FFT along z
arr = jnp.fft.fft(arr) # [x, y, z]
# Perform single gpu or distributed transpose
if comms == None:
arr = arr.transpose([1, 2, 0])
else:
arr = arr.reshape(shape[:-1]+[nx, shape[-1] // nx])
arr = arr.transpose([2, 1, 3, 0]) # [y, z, x]
arr, token = mpi4jax.alltoall(arr, comm=comms[0], token=token)
arr = arr.transpose([1, 2, 0, 3]).reshape(shape) # Now [y, z, x]
# Second FFT along x
arr = jnp.fft.fft(arr)
# Perform single gpu or distributed transpose
if comms == None:
arr = arr.transpose([1, 2, 0])
else:
arr = arr.reshape(shape[:-1]+[ny, shape[-1] // ny])
arr = arr.transpose([2, 1, 3, 0]) # [z, x, y]
arr, token = mpi4jax.alltoall(arr, comm=comms[1], token=token)
arr = arr.transpose([1, 2, 0, 3]).reshape(shape) # Now [z, x, y]
# Third FFT along y
arr = jnp.fft.fft(arr)
if comms == None:
return arr
else:
return arr, token
def ifft3d(arr, token=None, comms=None):
""" Let's assume that the data is distributed accross x
"""
if comms is not None:
shape = list(arr.shape)
nx = comms[0].Get_size()
ny = comms[1].Get_size()
# First FFT along y
arr = jnp.fft.ifft(arr) # Now [z, x, y]
# Perform single gpu or distributed transpose
if comms == None:
arr = arr.transpose([0, 2, 1])
else:
arr = arr.reshape(shape[:-1]+[ny, shape[-1] // ny])
arr = arr.transpose([2, 0, 3, 1]) # Now [z, y, x]
arr, token = mpi4jax.alltoall(arr, comm=comms[1], token=token)
arr = arr.transpose([1, 2, 0, 3]).reshape(shape) # Now [z,y,x]
# Second FFT along x
arr = jnp.fft.ifft(arr)
# Perform single gpu or distributed transpose
if comms == None:
arr = arr.transpose([2, 1, 0])
else:
arr = arr.reshape(shape[:-1]+[nx, shape[-1] // nx])
arr = arr.transpose([2, 3, 1, 0]) # now [x, y, z]
arr, token = mpi4jax.alltoall(arr, comm=comms[0], token=token)
arr = arr.transpose([1, 2, 0, 3]).reshape(shape) # Now [x,y,z]
# Third FFT along y
arr = jnp.fft.fft(arr)
if comms == None:
return arr
else:
return arr, token
def halo_reduce(arr, halo_size, token=None, comms=None):
# Perform halo exchange along x
rank_x = comms[0].Get_rank()
margin = arr[-2*halo_size:]
margin, token = mpi4jax.sendrecv(margin, margin, rank_x-1, rank_x+1,
comm=comms[0], token=token)
arr = arr.at[:2*halo_size].add(margin)
margin = arr[:2*halo_size]
margin, token = mpi4jax.sendrecv(margin, margin, rank_x+1, rank_x-1,
comm=comms[0], token=token)
arr = arr.at[-2*halo_size:].add(margin)
# Perform halo exchange along y
rank_y = comms[1].Get_rank()
margin = arr[:, -2*halo_size:]
margin, token = mpi4jax.sendrecv(margin, margin, rank_y-1, rank_y+1,
comm=comms[0], token=token)
arr = arr.at[:, :2*halo_size].add(margin)
margin = arr[:, :2*halo_size]
margin, token = mpi4jax.sendrecv(margin, margin, rank_y+1, rank_y-1,
comm=comms[0], token=token)
arr = arr.at[:, -2*halo_size:].add(margin)
return arr, token

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@ -2,95 +2,130 @@ import jax
import jax.numpy as jnp
import jax.lax as lax
from jaxpm.ops import halo_reduce
from jaxpm.kernels import fftk, cic_compensation
def cic_paint(mesh, positions):
""" Paints positions onto mesh
mesh: [nx, ny, nz]
positions: [npart, 3]
"""
positions = jnp.expand_dims(positions, 1)
floor = jnp.floor(positions)
connection = jnp.array([[[0, 0, 0], [1., 0, 0], [0., 1, 0],
[0., 0, 1], [1., 1, 0], [1., 0, 1],
[0., 1, 1], [1., 1, 1]]])
neighboor_coords = floor + connection
kernel = 1. - jnp.abs(positions - neighboor_coords)
kernel = kernel[..., 0] * kernel[..., 1] * kernel[..., 2]
def cic_paint(mesh, positions, halo_size=0, token=None, comms=None):
""" Paints positions onto mesh
mesh: [nx, ny, nz]
positions: [npart, 3]
"""
if comms is not None:
# Add some padding for the halo exchange
mesh = jnp.pad(mesh, [[halo_size, halo_size],
[halo_size, halo_size],
[0, 0]])
positions += jnp.array([halo_size, halo_size, 0]).reshape([-1, 3])
neighboor_coords = jnp.mod(neighboor_coords.reshape([-1,8,3]).astype('int32'), jnp.array(mesh.shape))
positions = jnp.expand_dims(positions, 1)
floor = jnp.floor(positions)
connection = jnp.array([[[0, 0, 0], [1., 0, 0], [0., 1, 0],
[0., 0, 1], [1., 1, 0], [1., 0, 1],
[0., 1, 1], [1., 1, 1]]])
dnums = jax.lax.ScatterDimensionNumbers(
update_window_dims=(),
inserted_window_dims=(0, 1, 2),
scatter_dims_to_operand_dims=(0, 1, 2))
mesh = lax.scatter_add(mesh,
neighboor_coords,
kernel.reshape([-1,8]),
dnums)
return mesh
neighboor_coords = floor + connection
kernel = 1. - jnp.abs(positions - neighboor_coords)
kernel = kernel[..., 0] * kernel[..., 1] * kernel[..., 2]
def cic_read(mesh, positions):
""" Paints positions onto mesh
mesh: [nx, ny, nz]
positions: [npart, 3]
"""
positions = jnp.expand_dims(positions, 1)
floor = jnp.floor(positions)
connection = jnp.array([[[0, 0, 0], [1., 0, 0], [0., 1, 0],
[0., 0, 1], [1., 1, 0], [1., 0, 1],
[0., 1, 1], [1., 1, 1]]])
neighboor_coords = jnp.mod(neighboor_coords.reshape(
[-1, 8, 3]).astype('int32'), jnp.array(mesh.shape))
neighboor_coords = floor + connection
kernel = 1. - jnp.abs(positions - neighboor_coords)
kernel = kernel[..., 0] * kernel[..., 1] * kernel[..., 2]
dnums = jax.lax.ScatterDimensionNumbers(
update_window_dims=(),
inserted_window_dims=(0, 1, 2),
scatter_dims_to_operand_dims=(0, 1, 2))
mesh = lax.scatter_add(mesh,
neighboor_coords,
kernel.reshape([-1, 8]),
dnums)
neighboor_coords = jnp.mod(neighboor_coords.astype('int32'), jnp.array(mesh.shape))
if comms == None:
return mesh
else:
mesh, token = halo_reduce(mesh, halo_size, token, comms)
return mesh[halo_size:-halo_size, halo_size:-halo_size]
def cic_read(mesh, positions, halo_size=0, token=None, comms=None):
""" Paints positions onto mesh
mesh: [nx, ny, nz]
positions: [npart, 3]
"""
if comms is not None:
# Add some padding and perfom hao exchange to retrieve
# neighboring regions
mesh = jnp.pad(mesh, [[halo_size, halo_size],
[halo_size, halo_size],
[0, 0]])
mesh, token = halo_reduce(mesh, halo_size, token, comms)
positions += jnp.array([halo_size, halo_size, 0]).reshape([-1, 3])
positions = jnp.expand_dims(positions, 1)
floor = jnp.floor(positions)
connection = jnp.array([[[0, 0, 0], [1., 0, 0], [0., 1, 0],
[0., 0, 1], [1., 1, 0], [1., 0, 1],
[0., 1, 1], [1., 1, 1]]])
neighboor_coords = floor + connection
kernel = 1. - jnp.abs(positions - neighboor_coords)
kernel = kernel[..., 0] * kernel[..., 1] * kernel[..., 2]
neighboor_coords = jnp.mod(
neighboor_coords.astype('int32'), jnp.array(mesh.shape))
res = (mesh[neighboor_coords[..., 0],
neighboor_coords[..., 1],
neighboor_coords[..., 3]]*kernel).sum(axis=-1)
if comms is not None:
return res
else:
return res, token
return (mesh[neighboor_coords[...,0],
neighboor_coords[...,1],
neighboor_coords[...,3]]*kernel).sum(axis=-1)
def cic_paint_2d(mesh, positions, weight):
""" Paints positions onto a 2d mesh
mesh: [nx, ny]
positions: [npart, 2]
weight: [npart]
"""
positions = jnp.expand_dims(positions, 1)
floor = jnp.floor(positions)
connection = jnp.array([[0, 0], [1., 0], [0., 1], [1., 1]])
""" Paints positions onto a 2d mesh
mesh: [nx, ny]
positions: [npart, 2]
weight: [npart]
"""
positions = jnp.expand_dims(positions, 1)
floor = jnp.floor(positions)
connection = jnp.array([[0, 0], [1., 0], [0., 1], [1., 1]])
neighboor_coords = floor + connection
kernel = 1. - jnp.abs(positions - neighboor_coords)
kernel = kernel[..., 0] * kernel[..., 1]
if weight is not None:
kernel = kernel * weight[...,jnp.newaxis]
neighboor_coords = jnp.mod(neighboor_coords.reshape([-1,4,2]).astype('int32'), jnp.array(mesh.shape))
neighboor_coords = floor + connection
kernel = 1. - jnp.abs(positions - neighboor_coords)
kernel = kernel[..., 0] * kernel[..., 1]
if weight is not None:
kernel = kernel * weight[..., jnp.newaxis]
neighboor_coords = jnp.mod(neighboor_coords.reshape(
[-1, 4, 2]).astype('int32'), jnp.array(mesh.shape))
dnums = jax.lax.ScatterDimensionNumbers(
update_window_dims=(),
inserted_window_dims=(0, 1),
scatter_dims_to_operand_dims=(0, 1))
mesh = lax.scatter_add(mesh,
neighboor_coords,
kernel.reshape([-1, 4]),
dnums)
return mesh
dnums = jax.lax.ScatterDimensionNumbers(
update_window_dims=(),
inserted_window_dims=(0, 1),
scatter_dims_to_operand_dims=(0, 1))
mesh = lax.scatter_add(mesh,
neighboor_coords,
kernel.reshape([-1,4]),
dnums)
return mesh
def compensate_cic(field):
"""
Compensate for CiC painting
Args:
field: input 3D cic-painted field
Returns:
compensated_field
"""
nc = field.shape
kvec = fftk(nc)
"""
Compensate for CiC painting
Args:
field: input 3D cic-painted field
Returns:
compensated_field
"""
nc = field.shape
kvec = fftk(nc)
delta_k = jnp.fft.rfftn(field)
delta_k = cic_compensation(kvec) * delta_k
return jnp.fft.irfftn(delta_k)
delta_k = jnp.fft.rfftn(field)
delta_k = cic_compensation(kvec) * delta_k
return jnp.fft.irfftn(delta_k)