2024-05-30 20:14:39 +08:00

287 lines
7.7 KiB
Python

"""XGBoost collective communication related API."""
import ctypes
import logging
import os
import pickle
from enum import IntEnum, unique
from typing import Any, Dict, List, Optional
import numpy as np
from ._typing import _T
from .core import _LIB, _check_call, build_info, c_str, make_jcargs, py_str
LOGGER = logging.getLogger("[xgboost.collective]")
def init(**args: Any) -> None:
"""Initialize the collective library with arguments.
Parameters
----------
args :
Keyword arguments representing the parameters and their values.
Accepted parameters:
- dmlc_communicator: The type of the communicator.
* rabit: Use Rabit. This is the default if the type is unspecified.
* federated: Use the gRPC interface for Federated Learning.
Only applicable to the Rabit communicator:
- dmlc_tracker_uri: Hostname of the tracker.
- dmlc_tracker_port: Port number of the tracker.
- dmlc_task_id: ID of the current task, can be used to obtain deterministic
- dmlc_retry: The number of retry when handling network errors.
- dmlc_timeout: Timeout in seconds.
- dmlc_nccl_path: Path to load (dlopen) nccl for GPU-based communication.
Only applicable to the Federated communicator (use upper case for environment
variables, use lower case for runtime configuration):
- federated_server_address: Address of the federated server.
- federated_world_size: Number of federated workers.
- federated_rank: Rank of the current worker.
- federated_server_cert: Server certificate file path. Only needed for the SSL
mode.
- federated_client_key: Client key file path. Only needed for the SSL mode.
- federated_client_cert: Client certificate file path. Only needed for the SSL
mode.
"""
_check_call(_LIB.XGCommunicatorInit(make_jcargs(**args)))
def finalize() -> None:
"""Finalize the communicator."""
_check_call(_LIB.XGCommunicatorFinalize())
def get_rank() -> int:
"""Get rank of current process.
Returns
-------
rank : int
Rank of current process.
"""
ret = _LIB.XGCommunicatorGetRank()
return ret
def get_world_size() -> int:
"""Get total number workers.
Returns
-------
n : int
Total number of process.
"""
ret = _LIB.XGCommunicatorGetWorldSize()
return ret
def is_distributed() -> int:
"""If the collective communicator is distributed."""
is_dist = _LIB.XGCommunicatorIsDistributed()
return is_dist
def communicator_print(msg: Any) -> None:
"""Print message to the communicator.
This function can be used to communicate the information of
the progress to the communicator.
Parameters
----------
msg : str
The message to be printed to the communicator.
"""
if not isinstance(msg, str):
msg = str(msg)
is_dist = _LIB.XGCommunicatorIsDistributed()
if is_dist != 0:
_check_call(_LIB.XGCommunicatorPrint(c_str(msg.strip())))
else:
print(msg.strip(), flush=True)
def get_processor_name() -> str:
"""Get the processor name.
Returns
-------
name : str
the name of processor(host)
"""
name_str = ctypes.c_char_p()
_check_call(_LIB.XGCommunicatorGetProcessorName(ctypes.byref(name_str)))
value = name_str.value
assert value
return py_str(value)
def broadcast(data: _T, root: int) -> _T:
"""Broadcast object from one node to all other nodes.
Parameters
----------
data : any type that can be pickled
Input data, if current rank does not equal root, this can be None
root : int
Rank of the node to broadcast data from.
Returns
-------
object : int
the result of broadcast.
"""
rank = get_rank()
length = ctypes.c_ulong()
if root == rank:
assert data is not None, "need to pass in data when broadcasting"
s = pickle.dumps(data, protocol=pickle.HIGHEST_PROTOCOL)
length.value = len(s)
# Run first broadcast
_check_call(
_LIB.XGCommunicatorBroadcast(
ctypes.byref(length), ctypes.sizeof(ctypes.c_ulong), root
)
)
if root != rank:
dptr = (ctypes.c_char * length.value)()
# run second
_check_call(
_LIB.XGCommunicatorBroadcast(
ctypes.cast(dptr, ctypes.c_void_p), length.value, root
)
)
data = pickle.loads(dptr.raw)
del dptr
else:
_check_call(
_LIB.XGCommunicatorBroadcast(
ctypes.cast(ctypes.c_char_p(s), ctypes.c_void_p), length.value, root
)
)
del s
return data
# enumeration of dtypes
def _map_dtype(dtype: np.dtype) -> int:
dtype_map = {
np.dtype("float16"): 0,
np.dtype("float32"): 1,
np.dtype("float64"): 2,
np.dtype("int8"): 4,
np.dtype("int16"): 5,
np.dtype("int32"): 6,
np.dtype("int64"): 7,
np.dtype("uint8"): 8,
np.dtype("uint16"): 9,
np.dtype("uint32"): 10,
np.dtype("uint64"): 11,
}
try:
dtype_map.update({np.dtype("float128"): 3})
except TypeError: # float128 doesn't exist on the system
pass
if dtype not in dtype_map:
raise TypeError(f"data type {dtype} is not supported on the current platform.")
return dtype_map[dtype]
@unique
class Op(IntEnum):
"""Supported operations for allreduce."""
MAX = 0
MIN = 1
SUM = 2
BITWISE_AND = 3
BITWISE_OR = 4
BITWISE_XOR = 5
def allreduce(data: np.ndarray, op: Op) -> np.ndarray: # pylint:disable=invalid-name
"""Perform allreduce, return the result.
Parameters
----------
data :
Input data.
op :
Reduction operator.
Returns
-------
result :
The result of allreduce, have same shape as data
Notes
-----
This function is not thread-safe.
"""
if not isinstance(data, np.ndarray):
raise TypeError("allreduce only takes in numpy.ndarray")
buf = data.ravel().copy()
_check_call(
_LIB.XGCommunicatorAllreduce(
buf.ctypes.data_as(ctypes.c_void_p),
buf.size,
_map_dtype(buf.dtype),
int(op),
)
)
return buf
def signal_error() -> None:
"""Kill the process."""
_check_call(_LIB.XGCommunicatorSignalError())
class CommunicatorContext:
"""A context controlling collective communicator initialization and finalization."""
def __init__(self, **args: Any) -> None:
self.args = args
key = "dmlc_nccl_path"
if args.get(key, None) is not None:
return
binfo = build_info()
if not binfo["USE_DLOPEN_NCCL"]:
return
try:
# PyPI package of NCCL.
from nvidia.nccl import lib
# There are two versions of nvidia-nccl, one is from PyPI, another one from
# nvidia-pyindex. We support only the first one as the second one is too old
# (2.9.8 as of writing).
if lib.__file__ is not None:
dirname: Optional[str] = os.path.dirname(lib.__file__)
else:
dirname = None
if dirname:
path = os.path.join(dirname, "libnccl.so.2")
self.args[key] = path
except ImportError:
pass
def __enter__(self) -> Dict[str, Any]:
init(**self.args)
assert is_distributed()
LOGGER.debug("-------------- communicator say hello ------------------")
return self.args
def __exit__(self, *args: List) -> None:
finalize()
LOGGER.debug("--------------- communicator say bye ------------------")