Files
sglang/python/sglang/srt/disaggregation/mooncake/conn.py
2025-05-28 00:40:54 -07:00

1127 lines
46 KiB
Python

from __future__ import annotations
import asyncio
import concurrent.futures
import dataclasses
import logging
import os
import queue
import socket
import struct
import threading
import time
from collections import defaultdict
from functools import cache
from typing import Dict, List, Optional, Tuple, Union
import numpy as np
import numpy.typing as npt
import requests
import zmq
from aiohttp import web
from sglang.srt.disaggregation.base.conn import (
BaseKVBootstrapServer,
BaseKVManager,
BaseKVReceiver,
BaseKVSender,
KVArgs,
KVPoll,
)
from sglang.srt.disaggregation.mooncake.transfer_engine import MooncakeTransferEngine
from sglang.srt.disaggregation.utils import (
DisaggregationMode,
group_concurrent_contiguous,
)
from sglang.srt.server_args import ServerArgs
from sglang.srt.utils import (
get_free_port,
get_int_env_var,
get_ip,
get_local_ip_by_remote,
)
logger = logging.getLogger(__name__)
class KVTransferError(Exception):
def __init__(self, bootstrap_room: int, failure_reason: str):
super().__init__(failure_reason)
self.bootstrap_room = bootstrap_room
self.failure_reason = failure_reason
def __str__(self):
return f"KVTransferError(bootstrap_room={self.bootstrap_room}): {self.failure_reason}"
# prefill
@dataclasses.dataclass
class TransferKVChunk:
room: int
prefill_kv_indices: npt.NDArray[np.int64]
index_slice: slice
is_last: bool
prefill_aux_index: Optional[int]
# decode
@dataclasses.dataclass
class TransferInfo:
room: int
endpoint: str
dst_port: int
mooncake_session_id: str
dst_kv_indices: npt.NDArray[np.int64]
dst_aux_index: int
required_dst_info_num: int
is_dummy: bool
@classmethod
def from_zmq(cls, msg: List[bytes]):
if msg[4] == b"" and msg[5] == b"":
is_dummy = True
dst_kv_indices = np.array([], dtype=np.int64)
dst_aux_index = None
else:
dst_kv_indices = np.frombuffer(msg[4], dtype=np.int64)
dst_aux_index = int(msg[5].decode("ascii"))
is_dummy = False
return cls(
room=int(msg[0].decode("ascii")),
endpoint=msg[1].decode("ascii"),
dst_port=int(msg[2].decode("ascii")),
mooncake_session_id=msg[3].decode("ascii"),
dst_kv_indices=dst_kv_indices,
dst_aux_index=dst_aux_index,
required_dst_info_num=int(msg[6].decode("ascii")),
is_dummy=is_dummy,
)
# decode
@dataclasses.dataclass
class KVArgsRegisterInfo:
room: str
endpoint: str
dst_port: int
mooncake_session_id: str
dst_kv_ptrs: list[int]
dst_aux_ptrs: list[int]
@classmethod
def from_zmq(cls, msg: List[bytes]):
return cls(
room=str(msg[0].decode("ascii")),
endpoint=msg[1].decode("ascii"),
dst_port=int(msg[2].decode("ascii")),
mooncake_session_id=msg[3].decode("ascii"),
dst_kv_ptrs=list(struct.unpack(f"{len(msg[4])//8}Q", msg[4])),
dst_aux_ptrs=list(struct.unpack(f"{len(msg[5])//8}Q", msg[5])),
)
class MooncakeKVManager(BaseKVManager):
def __init__(
self,
args: KVArgs,
disaggregation_mode: DisaggregationMode,
server_args: ServerArgs,
is_mla_backend: Optional[bool] = False,
):
self.kv_args = args
self.engine = MooncakeTransferEngine(
hostname=get_local_ip_by_remote(),
gpu_id=self.kv_args.gpu_id,
ib_device=self.kv_args.ib_device,
)
self.is_mla_backend = is_mla_backend
self.disaggregation_mode = disaggregation_mode
# for p/d multi node infer
self.bootstrap_port = server_args.disaggregation_bootstrap_port
self.dist_init_addr = server_args.dist_init_addr
self.tp_size = server_args.tp_size
self.dp_size = server_args.dp_size
self.enable_dp_attention = server_args.enable_dp_attention
if not server_args.enable_dp_attention and server_args.dp_size != 1:
raise ValueError(
"If dp_attention is not enabled, dp size must be 1 in disaggregation mode."
)
self.request_status: Dict[int, KVPoll] = {}
self.rank_port = None
self.server_socket = zmq.Context().socket(zmq.PULL)
self.register_buffer_to_engine()
if self.disaggregation_mode == DisaggregationMode.PREFILL:
self.transfer_queue = queue.Queue()
self.transfer_infos: Dict[int, Dict[str, TransferInfo]] = {}
self.decode_kv_args_table: Dict[str, KVArgsRegisterInfo] = {}
self.start_prefill_thread()
self._register_to_bootstrap()
self.session_failures = defaultdict(int)
self.failed_sessions = set()
self.session_lock = threading.Lock()
# Determine the number of threads to use for kv sender
cpu_count = os.cpu_count()
self.executor = concurrent.futures.ThreadPoolExecutor(
get_int_env_var(
"SGLANG_DISAGGREGATION_THREAD_POOL_SIZE",
min(max(1, cpu_count // 8), 8),
)
)
self.bootstrap_time_out = get_int_env_var(
"SGLANG_DISAGGREGATION_BOOTSTRAP_TIMEOUT", 30
)
elif self.disaggregation_mode == DisaggregationMode.DECODE:
self.heartbeat_failures = {}
self.session_pool = defaultdict(requests.Session)
self.session_pool_lock = threading.Lock()
self.addr_to_rooms_tracker = defaultdict(list)
self.connection_lock = threading.Lock()
# Heartbeat interval should be at least 2 seconds
self.heartbeat_interval = max(
float(os.getenv("SGLANG_DISAGGREGATION_HEARTBEAT_INTERVAL", 5.0)), 2.0
)
# Heartbeat failure should be at least 1
self.max_failures = max(
int(os.getenv("SGLANG_DISAGGREGATION_HEARTBEAT_MAX_FAILURE", 2)), 1
)
self.start_decode_thread()
self.connection_pool: Dict[str, Dict[str, Union[str, int]]] = {}
self.prefill_tp_size_table: Dict[str, int] = {}
self.prefill_dp_size_table: Dict[str, int] = {}
else:
raise ValueError(
f"Unsupported DisaggregationMode: {self.disaggregation_mode}"
)
self.failure_records: Dict[int, str] = {}
self.failure_lock = threading.Lock()
def register_buffer_to_engine(self):
for kv_data_ptr, kv_data_len in zip(
self.kv_args.kv_data_ptrs, self.kv_args.kv_data_lens
):
self.engine.register(kv_data_ptr, kv_data_len)
for aux_data_ptr, aux_data_len in zip(
self.kv_args.aux_data_ptrs, self.kv_args.aux_data_lens
):
self.engine.register(aux_data_ptr, aux_data_len)
@cache
def _connect(self, endpoint: str):
socket = zmq.Context().socket(zmq.PUSH)
socket.connect(endpoint)
return socket
def send_kvcache(
self,
mooncake_session_id: str,
prefill_kv_indices: npt.NDArray[np.int64],
dst_kv_ptrs: list[int],
dst_kv_indices: npt.NDArray[np.int64],
):
# Group by indices
prefill_kv_blocks, dst_kv_blocks = group_concurrent_contiguous(
prefill_kv_indices, dst_kv_indices
)
num_layers = len(self.kv_args.kv_data_ptrs)
layers_params = [
(
self.kv_args.kv_data_ptrs[layer_id],
dst_kv_ptrs[layer_id],
self.kv_args.kv_item_lens[layer_id],
)
for layer_id in range(num_layers)
]
# Worker function for processing a single layer
def process_layer(src_ptr: int, dst_ptr: int, item_len: int) -> int:
for prefill_index, decode_index in zip(prefill_kv_blocks, dst_kv_blocks):
src_addr = src_ptr + int(prefill_index[0]) * item_len
dst_addr = dst_ptr + int(decode_index[0]) * item_len
length = item_len * len(prefill_index)
status = self.engine.transfer_sync(
mooncake_session_id, src_addr, dst_addr, length
)
if status != 0:
return status
return 0
futures = [
self.executor.submit(
process_layer,
src_ptr,
dst_ptr,
item_len,
)
for (src_ptr, dst_ptr, item_len) in layers_params
]
for future in concurrent.futures.as_completed(futures):
status = future.result()
if status != 0:
for f in futures:
f.cancel()
return status
return 0
def send_aux(
self,
mooncake_session_id: str,
prefill_aux_index: int,
dst_aux_ptrs: list[int],
dst_aux_index: int,
):
aux_item_len = self.kv_args.aux_item_lens[0]
prefill_aux_addr = (
self.kv_args.aux_data_ptrs[0] + prefill_aux_index * aux_item_len
)
decode_aux_addr = dst_aux_ptrs[0] + dst_aux_index * aux_item_len
status = self.engine.transfer_sync(
mooncake_session_id, prefill_aux_addr, decode_aux_addr, aux_item_len
)
return status
def sync_status_to_decode_endpoint(
self, remote: str, dst_port: int, room: int, status: int
):
if ":" in remote:
remote = remote.split(":")[0]
self._connect("tcp://" + remote + ":" + str(dst_port)).send_multipart(
[
str(room).encode("ascii"),
str(status).encode("ascii"),
]
)
def start_prefill_thread(self):
self.rank_port = get_free_port()
self.server_socket.bind(f"tcp://{get_local_ip_by_remote()}:{self.rank_port}")
def bootstrap_thread():
"""This thread recvs pre-alloc notification from the decode engine"""
# KVPoll.Bootstrapping -> KVPoll.WaitingForInput
while True:
waiting_req_bytes = self.server_socket.recv_multipart()
room = waiting_req_bytes[0].decode("ascii")
mooncake_session_id = waiting_req_bytes[3].decode("ascii")
if room == "None":
self.decode_kv_args_table[mooncake_session_id] = (
KVArgsRegisterInfo.from_zmq(waiting_req_bytes)
)
with self.session_lock:
if mooncake_session_id in self.failed_sessions:
self.failed_sessions.remove(mooncake_session_id)
if mooncake_session_id in self.session_failures:
del self.session_failures[mooncake_session_id]
logger.debug(
f"Register KVArgs from {mooncake_session_id} successfully"
)
continue
else:
required_dst_info_num = int(waiting_req_bytes[6].decode("ascii"))
room = int(room)
if room not in self.transfer_infos:
self.transfer_infos[room] = {}
self.transfer_infos[room][mooncake_session_id] = (
TransferInfo.from_zmq(waiting_req_bytes)
)
# NOTE: after bootstrapping we can mark the req as waiting for input
if len(self.transfer_infos[room]) == required_dst_info_num:
self.update_status(room, KVPoll.WaitingForInput)
def transfer_thread():
# TODO: Shall we use KVPoll.Transferring state?
while True:
try:
kv_chunk: TransferKVChunk = self.transfer_queue.get(timeout=0.01)
reqs_to_be_processed = (
self.transfer_infos[kv_chunk.room].values()
if kv_chunk.room in self.transfer_infos
else []
)
polls = []
dst_ranks_infos = []
for req in reqs_to_be_processed:
if not req.is_dummy:
# Early exit if the request has failed
with self.session_lock:
if req.mooncake_session_id in self.failed_sessions:
self.record_failure(
kv_chunk.room,
f"Decode instance could be dead, remote mooncake session {req.mooncake_session_id} is not alive",
)
self.update_status(kv_chunk.room, KVPoll.Failed)
self.sync_status_to_decode_endpoint(
req.endpoint,
req.dst_port,
req.room,
KVPoll.Failed,
)
break
chunked_dst_kv_indice = req.dst_kv_indices[
kv_chunk.index_slice
]
# NOTE: This is temporarily a workaround to deal with the case where the prefill_kv_indices
# is mismatched with the dst_kv_indices when page size > 1, this should never happen.
if len(chunked_dst_kv_indice) < len(
kv_chunk.prefill_kv_indices
):
kv_chunk.prefill_kv_indices = (
kv_chunk.prefill_kv_indices[
len(chunked_dst_kv_indice)
]
)
logger.warning(
f"len(chunked_dst_kv_indice) = {len(chunked_dst_kv_indice)}, len(kv_chunk.prefill_kv_indices) = {len(kv_chunk.prefill_kv_indices)}"
)
ret = self.send_kvcache(
req.mooncake_session_id,
kv_chunk.prefill_kv_indices,
self.decode_kv_args_table[
req.mooncake_session_id
].dst_kv_ptrs,
chunked_dst_kv_indice,
)
if ret != 0:
with self.session_lock:
self.session_failures[req.mooncake_session_id] += 1
# Failures should never happen if the session is not dead, if the session fails once, mark it as failed
if (
self.session_failures[req.mooncake_session_id]
>= 1
):
self.failed_sessions.add(
req.mooncake_session_id
)
logger.error(
f"Session {req.mooncake_session_id} failed."
)
self.record_failure(
kv_chunk.room,
f"Failed to send kv chunk of {kv_chunk.room} to {req.endpoint}:{req.dst_port}",
)
self.update_status(kv_chunk.room, KVPoll.Failed)
self.sync_status_to_decode_endpoint(
req.endpoint, req.dst_port, req.room, KVPoll.Failed
)
break
if kv_chunk.is_last:
# Only the last chunk we need to send the aux data
ret = self.send_aux(
req.mooncake_session_id,
kv_chunk.prefill_aux_index,
self.decode_kv_args_table[
req.mooncake_session_id
].dst_aux_ptrs,
req.dst_aux_index,
)
polls.append(True if ret == 0 else False)
dst_ranks_infos.append(
(req.endpoint, req.dst_port, req.room)
)
# Only sync status when all the dst ranks have received the kvcache
if len(polls) == req.required_dst_info_num:
status = (
KVPoll.Success if all(polls) else KVPoll.Failed
)
self.update_status(req.room, status)
for endpoint, dst_port, room in dst_ranks_infos:
self.sync_status_to_decode_endpoint(
endpoint, dst_port, room, status
)
else:
# Dummy request means the decode instance is not used, so its status can be marked as success directly
# Dummy request does not need to sync status to decode endpoint
if kv_chunk.is_last and req.room in self.request_status:
self.update_status(req.room, KVPoll.Success)
if (
kv_chunk.room not in self.request_status
or self.check_status(kv_chunk.room) == KVPoll.Success
):
if kv_chunk.room in self.transfer_infos:
self.transfer_infos.pop(kv_chunk.room)
except queue.Empty:
continue
except Exception as e:
# NOTE(shangming): Remove this when we make sure the transfer thread is bug-free
raise RuntimeError(
f"Transfer thread failed because of {e}. Prefill instance with bootstrap_port={self.bootstrap_port} is dead."
)
threading.Thread(target=bootstrap_thread).start()
threading.Thread(target=transfer_thread).start()
def start_decode_thread(self):
self.rank_port = get_free_port()
self.server_socket.bind(f"tcp://{get_local_ip_by_remote()}:{self.rank_port}")
def decode_thread():
while True:
(bootstrap_room, status) = self.server_socket.recv_multipart()
status = int(status.decode("ascii"))
bootstrap_room = int(bootstrap_room.decode("ascii"))
if status == KVPoll.Failed:
self.record_failure(
bootstrap_room,
f"Failed to get kvcache from prefill instance, it might be dead",
)
self.update_status(bootstrap_room, status)
def heartbeat_checker():
while True:
time.sleep(self.heartbeat_interval)
with self.connection_lock:
addresses = list(self.prefill_dp_size_table.keys())
for bootstrap_addr in addresses:
session = None
try:
with self.session_pool_lock:
session = self.session_pool[bootstrap_addr]
response = session.get(
f"http://{bootstrap_addr}/health",
timeout=(2, 3),
headers={"Connection": "keep-alive"},
)
if response.status_code == 200:
self.heartbeat_failures[bootstrap_addr] = 0
for bootstrap_room in self.addr_to_rooms_tracker[
bootstrap_addr
]:
# Remove KVPoll.Success requests from the map
if bootstrap_room not in self.request_status:
self.addr_to_rooms_tracker[bootstrap_addr].remove(
bootstrap_room
)
else:
logger.info(
f"Attempting to reconnect to {bootstrap_addr}..."
)
self.heartbeat_failures[bootstrap_addr] = (
self.heartbeat_failures.get(bootstrap_addr, 0) + 1
)
with self.session_pool_lock:
if bootstrap_addr in self.session_pool:
del self.session_pool[bootstrap_addr]
except Exception:
logger.info(f"Attempting to reconnect to {bootstrap_addr}...")
self.heartbeat_failures[bootstrap_addr] = (
self.heartbeat_failures.get(bootstrap_addr, 0) + 1
)
if (
self.heartbeat_failures.get(bootstrap_addr, 0)
>= self.max_failures
):
self._handle_node_failure(bootstrap_addr)
with self.session_pool_lock:
if bootstrap_addr in self.session_pool:
del self.session_pool[bootstrap_addr]
threading.Thread(target=decode_thread).start()
threading.Thread(target=heartbeat_checker).start()
def add_transfer_request(
self,
bootstrap_room: int,
kv_indices: npt.NDArray[np.int64],
index_slice: slice,
is_last: bool,
aux_index: Optional[int] = None,
):
assert self.disaggregation_mode == DisaggregationMode.PREFILL
assert not is_last or (is_last and aux_index is not None)
if (
bootstrap_room not in self.request_status
or self.check_status(bootstrap_room) == KVPoll.Failed
):
logger.debug(
"Request with bootstrap_room=%s already failed", bootstrap_room
)
return
self.transfer_queue.put(
TransferKVChunk(
room=bootstrap_room,
prefill_kv_indices=kv_indices,
index_slice=index_slice,
is_last=is_last,
prefill_aux_index=aux_index,
)
)
self.update_status(bootstrap_room, KVPoll.WaitingForInput)
def check_status(self, bootstrap_room: int):
return self.request_status[bootstrap_room]
def update_status(self, bootstrap_room: int, status: KVPoll):
if bootstrap_room not in self.request_status:
self.request_status[bootstrap_room] = status
else:
# NOTE: status is only allowed to be incremented unless it is KVPoll.Failed
if status == KVPoll.Failed:
self.request_status[bootstrap_room] = KVPoll.Failed
else:
self.request_status[bootstrap_room] = max(
self.request_status[bootstrap_room], status
)
def record_failure(self, bootstrap_room: int, failure_reason: str):
with self.failure_lock:
self.failure_records[bootstrap_room] = failure_reason
def get_session_id(self):
return self.engine.get_session_id()
def _register_to_bootstrap(self):
"""Register KVSender to bootstrap server via HTTP POST."""
if self.dist_init_addr:
ip_address = socket.gethostbyname(self.dist_init_addr.split(":")[0])
else:
ip_address = get_ip()
bootstrap_server_url = f"{ip_address}:{self.bootstrap_port}"
url = f"http://{bootstrap_server_url}/route"
payload = {
"role": "Prefill",
"tp_size": self.tp_size,
"dp_size": self.dp_size,
"rank_ip": get_local_ip_by_remote(),
"rank_port": self.rank_port,
"engine_rank": self.kv_args.engine_rank,
}
try:
response = requests.put(url, json=payload, timeout=5)
if response.status_code == 200:
logger.debug("Prefill successfully registered to bootstrap server.")
else:
logger.error(
f"Prefill instance failed to connect to bootstrap server: {response.status_code}, {response.text}"
)
except Exception as e:
logger.error(
f"Prefill instance failed to register to bootstrap server: {e}"
)
def _handle_node_failure(self, failed_bootstrap_addr):
with self.connection_lock:
keys_to_remove = [
k for k in self.connection_pool if k.startswith(failed_bootstrap_addr)
]
for k in keys_to_remove:
del self.connection_pool[k]
if failed_bootstrap_addr in self.prefill_tp_size_table:
del self.prefill_tp_size_table[failed_bootstrap_addr]
if failed_bootstrap_addr in self.prefill_dp_size_table:
del self.prefill_dp_size_table[failed_bootstrap_addr]
possible_affected_rooms = self.addr_to_rooms_tracker.get(
failed_bootstrap_addr, []
)
if failed_bootstrap_addr in self.addr_to_rooms_tracker:
del self.addr_to_rooms_tracker[failed_bootstrap_addr]
# Report the requests associated with the failed bootstrap addr and mark their status as KVPoll.Failed
affected_rooms = []
for room in possible_affected_rooms:
if (
room in self.request_status
and self.check_status(room) != KVPoll.Success
):
self.record_failure(
room,
f"Losing connection with prefill instance (bootstrap_addr: {failed_bootstrap_addr})",
)
self.update_status(room, KVPoll.Failed)
affected_rooms.append(room)
logger.error(
f"Losing connection with prefill instance (bootstrap_addr: {failed_bootstrap_addr}), affected {len(affected_rooms)} requests"
)
class MooncakeKVSender(BaseKVSender):
def __init__(
self, mgr: MooncakeKVManager, bootstrap_addr: str, bootstrap_room: int
):
self.kv_mgr = mgr
self.bootstrap_room = bootstrap_room
self.kv_mgr.update_status(bootstrap_room, KVPoll.Bootstrapping)
self.aux_index = None
self.bootstrap_server_url = bootstrap_addr
self.init_time = time.time()
self.conclude_state = None
# inner state
self.curr_idx = 0
def init(self, num_kv_indices: int, aux_index: Optional[int] = None):
self.num_kv_indices = num_kv_indices
self.aux_index = aux_index
def send(
self,
kv_indices: npt.NDArray[np.int64],
):
index_slice = slice(self.curr_idx, self.curr_idx + len(kv_indices))
self.curr_idx += len(kv_indices)
is_last = self.curr_idx == self.num_kv_indices
if not is_last:
self.kv_mgr.add_transfer_request(
self.bootstrap_room, kv_indices, index_slice, False
)
else:
self.kv_mgr.add_transfer_request(
self.bootstrap_room,
kv_indices,
index_slice,
True,
aux_index=self.aux_index,
)
def poll(self) -> KVPoll:
if self.conclude_state is None:
status = self.kv_mgr.check_status(self.bootstrap_room)
if status in (KVPoll.Success, KVPoll.Failed):
self.conclude_state = status
elif status == KVPoll.Bootstrapping:
now = time.time()
elapsed = now - self.init_time
if elapsed >= self.kv_mgr.bootstrap_time_out:
self.kv_mgr.record_failure(
self.bootstrap_room,
f"Request {self.bootstrap_room} timed out after {elapsed:.1f}s in KVPoll.Bootstrapping",
)
self.conclude_state = KVPoll.Failed
return KVPoll.Failed
return status
else:
return self.conclude_state
def clear(self) -> None:
if self.bootstrap_room in self.kv_mgr.request_status:
self.kv_mgr.request_status.pop(self.bootstrap_room)
def failure_exception(self):
self.clear()
# Explicitly set the status to failure since this request has failed in another rank
if self.conclude_state is None:
self.conclude_state = KVPoll.Failed
with self.kv_mgr.failure_lock:
failure_reason = self.kv_mgr.failure_records.pop(
self.bootstrap_room, "Failed due to an unknown reason from another rank"
)
raise KVTransferError(self.bootstrap_room, failure_reason)
class MooncakeKVReceiver(BaseKVReceiver):
_ctx = zmq.Context()
_socket_cache = {}
_socket_locks = {}
_global_lock = threading.Lock()
def __init__(
self,
mgr: MooncakeKVManager,
bootstrap_addr: str,
bootstrap_room: Optional[int] = None,
):
self.bootstrap_room = bootstrap_room
self.bootstrap_addr = bootstrap_addr
self.kv_mgr = mgr
self.session_id = self.kv_mgr.get_session_id()
self.kv_mgr.update_status(self.bootstrap_room, KVPoll.Bootstrapping)
self.conclude_state = None
if self.bootstrap_addr not in self.kv_mgr.prefill_dp_size_table:
self.prefill_tp_size, self.prefill_dp_size = (
self._get_prefill_parallel_info_from_server()
)
if self.prefill_tp_size is None or self.prefill_dp_size is None:
self.kv_mgr.record_failure(
self.bootstrap_room,
f"Could not fetch prefill parallel info from bootstrap_addr: {self.bootstrap_addr}",
)
self.kv_mgr.update_status(self.bootstrap_room, KVPoll.Failed)
return
else:
logger.debug(
f"Fetch prefill parallel info from [{self.bootstrap_addr}]: DP size:{self.prefill_dp_size}, TP size:{self.prefill_tp_size}"
)
self.kv_mgr.prefill_tp_size_table[self.bootstrap_addr] = (
self.prefill_tp_size
)
self.kv_mgr.prefill_dp_size_table[self.bootstrap_addr] = (
self.prefill_dp_size
)
else:
self.prefill_tp_size = self.kv_mgr.prefill_tp_size_table[
self.bootstrap_addr
]
self.prefill_dp_size = self.kv_mgr.prefill_dp_size_table[
self.bootstrap_addr
]
# Currently, we don't allow prefill instance and decode instance to
# have different TP sizes per DP rank, except for models using MLA.
local_tp_size_per_dp_rank = self.kv_mgr.tp_size // self.kv_mgr.dp_size
prefill_tp_size_per_dp_rank = self.prefill_tp_size // self.prefill_dp_size
if local_tp_size_per_dp_rank == prefill_tp_size_per_dp_rank:
self.target_tp_rank = (
self.kv_mgr.kv_args.engine_rank % local_tp_size_per_dp_rank
)
self.required_dst_info_num = 1
self.target_tp_ranks = [self.target_tp_rank]
elif local_tp_size_per_dp_rank > prefill_tp_size_per_dp_rank:
assert (
self.kv_mgr.is_mla_backend
), "PD with different TP sizes per DP rank is not yet supported for non-MLA models"
self.target_tp_rank = (
self.kv_mgr.kv_args.engine_rank % local_tp_size_per_dp_rank
) // (local_tp_size_per_dp_rank // prefill_tp_size_per_dp_rank)
self.required_dst_info_num = (
local_tp_size_per_dp_rank // prefill_tp_size_per_dp_rank
)
self.target_tp_ranks = [self.target_tp_rank]
else:
assert (
self.kv_mgr.is_mla_backend
), "PD with different TP sizes per DP rank is not yet supported for non-MLA models"
# For non-MLA models, one decode rank needs to retrieve KVCache from multiple prefill ranks for non MLA models;
self.target_tp_ranks = [
rank
for rank in range(
(self.kv_mgr.kv_args.engine_rank % local_tp_size_per_dp_rank)
* (prefill_tp_size_per_dp_rank // local_tp_size_per_dp_rank),
(self.kv_mgr.kv_args.engine_rank % local_tp_size_per_dp_rank + 1)
* (prefill_tp_size_per_dp_rank // local_tp_size_per_dp_rank),
)
]
# For MLA models, we can retrieve KVCache from only one prefill rank, but we still need to maintain
# multiple connections in the connection pool and have to send dummy requests to other prefill ranks,
# or the KVPoll will never be set correctly
self.target_tp_rank = self.target_tp_ranks[0]
self.required_dst_info_num = 1
self.target_dp_group = self.bootstrap_room % self.prefill_dp_size
# NOTE: key distinguished by bootstrap_addr, target_dp_group, and target_tp_rank
bootstrap_key = (
f"{self.bootstrap_addr}_{self.target_dp_group}_{self.target_tp_rank}"
)
if bootstrap_key not in self.kv_mgr.connection_pool:
bootstrap_infos = []
for target_tp_rank in self.target_tp_ranks:
bootstrap_info = self._get_bootstrap_info_from_server(
target_tp_rank,
self.target_dp_group,
)
if bootstrap_info is not None:
# NOTE: only support MLA for now: select one prefill rank as real rank
bootstrap_info["is_dummy"] = not bool(
target_tp_rank == self.target_tp_rank
or self.target_tp_rank is None
)
logger.debug(
f"Fetched bootstrap info: {bootstrap_info} for DP {self.target_dp_group} TP {target_tp_rank}"
)
bootstrap_infos.append(bootstrap_info)
else:
self.kv_mgr.record_failure(
self.bootstrap_room,
f"Could not fetch bootstrap info for engine rank: {self.kv_mgr.kv_args.engine_rank} and target_dp_group: {self.target_dp_group}",
)
self.kv_mgr.update_status(self.bootstrap_room, KVPoll.Failed)
return
self.bootstrap_infos = bootstrap_infos
self.kv_mgr.connection_pool[bootstrap_key] = self.bootstrap_infos
# Register kv_args only once to prefill KVManager according to the info fetched from the bootstrap server
self._register_kv_args()
else:
self.bootstrap_infos = self.kv_mgr.connection_pool[bootstrap_key]
assert len(self.bootstrap_infos) > 0
self.kv_mgr.addr_to_rooms_tracker[self.bootstrap_addr].append(
self.bootstrap_room
)
self.kv_mgr.update_status(self.bootstrap_room, KVPoll.WaitingForInput)
def _get_bootstrap_info_from_server(self, engine_rank, target_dp_group):
"""Fetch the bootstrap info from the bootstrap server."""
try:
url = f"http://{self.bootstrap_addr}/route?engine_rank={engine_rank}&target_dp_group={target_dp_group}"
response = requests.get(url, timeout=5)
if response.status_code == 200:
bootstrap_info = response.json()
return bootstrap_info
else:
logger.error(
f"Failed to get prefill server info: {response.status_code}, {response.text}"
)
return None
except Exception as e:
logger.error(f"Error fetching prefill info from bootstrap: {e}")
return None
def _get_prefill_parallel_info_from_server(self) -> Tuple[int, int]:
"""Fetch the prefill parallel info from the bootstrap server."""
try:
url = f"http://{self.bootstrap_addr}/route?engine_rank={-1}&target_dp_group={-1}"
response = requests.get(url)
if response.status_code == 200:
prefill_parallel_info = response.json()
return int(prefill_parallel_info["prefill_tp_size"]), int(
prefill_parallel_info["prefill_dp_size"]
)
else:
logger.error(
f"Failed to get prefill parallel info: {response.status_code}, {response.text}"
)
return None, None
except Exception as e:
logger.error(f"Error fetching prefill parallel info from bootstrap: {e}")
return None, None
def _register_kv_args(self):
for bootstrap_info in self.bootstrap_infos:
self.prefill_server_url = (
f"{bootstrap_info['rank_ip']}:{bootstrap_info['rank_port']}"
)
packed_kv_data_ptrs = b"".join(
struct.pack("Q", ptr) for ptr in self.kv_mgr.kv_args.kv_data_ptrs
)
packed_aux_data_ptrs = b"".join(
struct.pack("Q", ptr) for ptr in self.kv_mgr.kv_args.aux_data_ptrs
)
sock, lock = self._connect("tcp://" + self.prefill_server_url)
with lock:
sock.send_multipart(
[
"None".encode("ascii"),
get_local_ip_by_remote().encode("ascii"),
str(self.kv_mgr.rank_port).encode("ascii"),
self.session_id.encode("ascii"),
packed_kv_data_ptrs,
packed_aux_data_ptrs,
]
)
@classmethod
def _connect(cls, endpoint: str):
with cls._global_lock:
if endpoint not in cls._socket_cache:
sock = cls._ctx.socket(zmq.PUSH)
sock.connect(endpoint)
cls._socket_cache[endpoint] = sock
cls._socket_locks[endpoint] = threading.Lock()
return cls._socket_cache[endpoint], cls._socket_locks[endpoint]
def init(self, kv_indices: npt.NDArray[np.int64], aux_index: Optional[int] = None):
for bootstrap_info in self.bootstrap_infos:
self.prefill_server_url = (
f"{bootstrap_info['rank_ip']}:{bootstrap_info['rank_port']}"
)
is_dummy = bootstrap_info["is_dummy"]
sock, lock = self._connect("tcp://" + self.prefill_server_url)
with lock:
sock.send_multipart(
[
str(self.bootstrap_room).encode("ascii"),
get_local_ip_by_remote().encode("ascii"),
str(self.kv_mgr.rank_port).encode("ascii"),
self.session_id.encode("ascii"),
kv_indices.tobytes() if not is_dummy else b"",
str(aux_index).encode("ascii") if not is_dummy else b"",
str(self.required_dst_info_num).encode("ascii"),
]
)
def poll(self) -> KVPoll:
if self.conclude_state is None:
status = self.kv_mgr.check_status(self.bootstrap_room)
if status in (KVPoll.Success, KVPoll.Failed):
self.conclude_state = status
return status
else:
return self.conclude_state
def clear(self) -> None:
if self.bootstrap_room in self.kv_mgr.request_status:
self.kv_mgr.request_status.pop(self.bootstrap_room)
def failure_exception(self):
self.clear()
# Explicitly set the status to failure since this request has failed in another rank
if self.conclude_state is None:
self.conclude_state = KVPoll.Failed
with self.kv_mgr.failure_lock:
failure_reason = self.kv_mgr.failure_records.pop(
self.bootstrap_room, "Failed due to an unknown reason from another rank"
)
raise KVTransferError(self.bootstrap_room, failure_reason)
class MooncakeKVBootstrapServer(BaseKVBootstrapServer):
def __init__(self, port: int):
self.port = port
self.app = web.Application()
self.store = dict()
self.lock = asyncio.Lock()
self._setup_routes()
self.tp_size = None
self.dp_size = None
self.tp_size_per_dp_rank = None
self.prefill_port_table: Dict[int, Dict[int, Dict[str, Union[str, int]]]] = {}
# Start bootstrap server
self.thread = threading.Thread(target=self._run_server, daemon=True)
self.run()
def run(self):
self.thread.start()
def _setup_routes(self):
self.app.router.add_route("*", "/route", self._handle_route)
self.app.router.add_get("/health", self._handle_health_check)
async def _handle_health_check(self, request):
return web.Response(text="OK", status=200)
async def _handle_route(self, request: web.Request):
method = request.method
if method == "PUT":
return await self._handle_route_put(request)
elif method == "GET":
return await self._handle_route_get(request)
else:
return web.Response(
text="Method not allowed", status=405, content_type="application/json"
)
async def _handle_route_put(self, request: web.Request):
data = await request.json()
role = data["role"]
tp_size = data["tp_size"]
dp_size = data["dp_size"]
rank_ip = data["rank_ip"]
rank_port = int(data["rank_port"])
engine_rank = int(data["engine_rank"])
if self.tp_size is None:
self.tp_size = tp_size
if self.dp_size is None:
self.dp_size = dp_size
tp_size_per_dp_rank = tp_size // dp_size
if self.tp_size_per_dp_rank is None:
self.tp_size_per_dp_rank = tp_size_per_dp_rank
if role == "Prefill":
dp_group = engine_rank // tp_size_per_dp_rank
tp_rank_in_dp_group = engine_rank % tp_size_per_dp_rank
# Add lock to make sure thread-safe
async with self.lock:
if dp_group not in self.prefill_port_table:
self.prefill_port_table[dp_group] = {}
self.prefill_port_table[dp_group][tp_rank_in_dp_group] = {
"rank_ip": rank_ip,
"rank_port": rank_port,
}
logger.debug(
f"Register prefill bootstrap: {engine_rank} with rank_ip: {rank_ip} and rank_port: {rank_port}"
)
return web.Response(text="OK", status=200)
async def _handle_route_get(self, request: web.Request):
engine_rank = request.query.get("engine_rank")
target_dp_group = request.query.get("target_dp_group")
if not engine_rank or not target_dp_group:
return web.Response(text="Missing inputs for bootstrap server.", status=400)
# Currently we use engine_rank == -1 and target_dp_group == -1 to sync dp size
if int(engine_rank) == -1 and int(target_dp_group) == -1:
prefill_parallel_info = {
"prefill_tp_size": self.tp_size,
"prefill_dp_size": self.dp_size,
}
return web.json_response(prefill_parallel_info, status=200)
# Find corresponding prefill info
async with self.lock:
bootstrap_info = self.prefill_port_table[int(target_dp_group)][
int(engine_rank)
]
if bootstrap_info is not None:
return web.json_response(bootstrap_info, status=200)
else:
return web.Response(text="Bootstrap info not Found", status=404)
def _run_server(self):
try:
# Event Loop
self._loop = asyncio.new_event_loop()
asyncio.set_event_loop(self._loop)
access_log = None
if logging.getLogger(__name__).getEffectiveLevel() <= logging.DEBUG:
access_log = self.app.logger
self._runner = web.AppRunner(self.app, access_log=access_log)
self._loop.run_until_complete(self._runner.setup())
site = web.TCPSite(self._runner, port=self.port)
self._loop.run_until_complete(site.start())
self._loop.run_forever()
except Exception as e:
logger.error(f"Server error: {str(e)}")
finally:
# Cleanup
self._loop.run_until_complete(self._runner.cleanup())
self._loop.close()
def close(self):
"""Shutdown"""
if self._loop is not None and self._loop.is_running():
self._loop.call_soon_threadsafe(self._loop.stop)
logger.info("Stopping server loop...")
if self.thread.is_alive():
self.thread.join(timeout=2)
logger.info("Server thread stopped")
def poll(self) -> KVPoll: ...