Files
sglang/python/sglang/srt/managers/data_parallel_controller.py
2024-11-28 00:22:39 -08:00

246 lines
8.2 KiB
Python

# Copyright 2023-2024 SGLang Team
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
# ==============================================================================
"""A controller that dispatches requests to multiple data parallel workers."""
import logging
import multiprocessing as mp
import signal
import threading
from enum import Enum, auto
import psutil
import zmq
from sglang.srt.managers.io_struct import (
TokenizedEmbeddingReqInput,
TokenizedGenerateReqInput,
)
from sglang.srt.managers.scheduler import run_scheduler_process
from sglang.srt.server_args import PortArgs, ServerArgs
from sglang.srt.utils import bind_port, configure_logger, get_zmq_socket
from sglang.utils import get_exception_traceback
logger = logging.getLogger(__name__)
class LoadBalanceMethod(Enum):
"""Load balance method."""
ROUND_ROBIN = auto()
SHORTEST_QUEUE = auto()
@classmethod
def from_str(cls, method: str):
method = method.upper()
try:
return cls[method]
except KeyError as exc:
raise ValueError(f"Invalid load balance method: {method}") from exc
class DataParallelController:
"""A controller that dispatches requests to multiple data parallel workers."""
def __init__(self, server_args, port_args) -> None:
# Parse args
self.server_args = server_args
self.port_args = port_args
self.load_balance_method = LoadBalanceMethod.from_str(
server_args.load_balance_method
)
# Init inter-process communication
self.context = zmq.Context(1 + server_args.dp_size)
self.recv_from_tokenizer = get_zmq_socket(
self.context, zmq.PULL, port_args.scheduler_input_ipc_name
)
# Dispatch method
self.round_robin_counter = 0
dispatch_lookup = {
LoadBalanceMethod.ROUND_ROBIN: self.round_robin_scheduler,
LoadBalanceMethod.SHORTEST_QUEUE: self.shortest_queue_scheduler,
}
self.dispatching = dispatch_lookup[self.load_balance_method]
# Start data parallel workers
base_gpu_id = 0
self.workers = [None] * server_args.dp_size
threads = []
sockets = []
for dp_rank in range(server_args.dp_size):
tmp_port_args = PortArgs.init_new(server_args)
tmp_port_args.tokenizer_ipc_name = port_args.tokenizer_ipc_name
tmp_port_args.detokenizer_ipc_name = port_args.detokenizer_ipc_name
if server_args.enable_dp_attention:
# Data parallelism resues the tensor parallelism group,
# so all dp ranks should use the same nccl port.
tmp_port_args.nccl_port = port_args.nccl_port
else:
# This port is checked free in PortArgs.init_new.
# We hold it first so that the next dp worker gets a different port
sockets.append(bind_port(tmp_port_args.nccl_port))
# Create a thread for each worker
thread = threading.Thread(
target=self.launch_worker_func,
args=(server_args, tmp_port_args, base_gpu_id, dp_rank),
)
threads.append(thread)
base_gpu_id += 1 if server_args.enable_dp_attention else server_args.tp_size
# Free all sockets before starting the threads to launch TP workers
for sock in sockets:
sock.close()
# Start all threads
for thread in threads:
thread.start()
for thread in threads:
thread.join()
def launch_worker_func(
self,
server_args: ServerArgs,
port_args: PortArgs,
base_gpu_id: int,
dp_rank: int,
):
logger.info(f"Launch DP{dp_rank} starting at GPU #{base_gpu_id}.")
launch_func_ = (
self.launch_tensor_parallel_process
if server_args.enable_dp_attention
else self.launch_tensor_parallel_group
)
self.workers[dp_rank] = launch_func_(
server_args,
port_args,
base_gpu_id,
dp_rank,
)
def launch_tensor_parallel_group(
self,
server_args: ServerArgs,
port_args: PortArgs,
base_gpu_id: int,
dp_rank: int,
):
# Launch tensor parallel scheduler processes
scheduler_procs = []
scheduler_pipe_readers = []
tp_size_per_node = server_args.tp_size // server_args.nnodes
tp_rank_range = range(
tp_size_per_node * server_args.node_rank,
tp_size_per_node * (server_args.node_rank + 1),
)
for tp_rank in tp_rank_range:
reader, writer = mp.Pipe(duplex=False)
gpu_id = server_args.base_gpu_id + base_gpu_id + tp_rank % tp_size_per_node
proc = mp.Process(
target=run_scheduler_process,
args=(server_args, port_args, gpu_id, tp_rank, dp_rank, writer),
)
proc.start()
scheduler_procs.append(proc)
scheduler_pipe_readers.append(reader)
send_to = get_zmq_socket(
self.context, zmq.PUSH, port_args.scheduler_input_ipc_name
)
# Wait for model to finish loading and get max token nums
scheduler_info = []
for i in range(len(scheduler_pipe_readers)):
scheduler_info.append(scheduler_pipe_readers[i].recv())
self.max_total_num_tokens = scheduler_info[0]["max_total_num_tokens"]
return send_to
def launch_tensor_parallel_process(
self,
server_args: ServerArgs,
port_args: PortArgs,
base_gpu_id: int,
dp_rank: int,
):
reader, writer = mp.Pipe(duplex=False)
gpu_id = base_gpu_id
tp_rank = dp_rank
proc = mp.Process(
target=run_scheduler_process,
args=(server_args, port_args, gpu_id, tp_rank, dp_rank, writer),
)
proc.start()
send_to = get_zmq_socket(
self.context, zmq.PUSH, port_args.scheduler_input_ipc_name
)
scheduler_info = reader.recv()
self.max_total_num_tokens = scheduler_info["max_total_num_tokens"]
return send_to
def round_robin_scheduler(self, req):
self.workers[self.round_robin_counter].send_pyobj(req)
self.round_robin_counter = (self.round_robin_counter + 1) % len(self.workers)
def shortest_queue_scheduler(self, input_requests):
raise NotImplementedError()
def event_loop(self):
while True:
while True:
try:
recv_req = self.recv_from_tokenizer.recv_pyobj(zmq.NOBLOCK)
except zmq.ZMQError:
break
if isinstance(
recv_req,
(
TokenizedGenerateReqInput,
TokenizedEmbeddingReqInput,
),
):
self.dispatching(recv_req)
else:
# Send other control messages to all workers
for worker in self.workers:
worker.send_pyobj(recv_req)
def run_data_parallel_controller_process(
server_args: ServerArgs,
port_args: PortArgs,
pipe_writer,
):
configure_logger(server_args)
parent_process = psutil.Process().parent()
try:
controller = DataParallelController(server_args, port_args)
pipe_writer.send(
{"status": "ready", "max_total_num_tokens": controller.max_total_num_tokens}
)
controller.event_loop()
except Exception:
traceback = get_exception_traceback()
logger.error(f"DataParallelController hit an exception: {traceback}")
parent_process.send_signal(signal.SIGQUIT)