Files
exo/tests/headless_runner.py
Jake Hillion 9357503c6f downloads: refactor to run at node level
The Worker previously owned the ShardDownloader directly via dependency
injection, which prevented --no-worker nodes from downloading and made
it impossible for multiple Workers to share a single downloader instance.

Moved download functionality to a new DownloadCoordinator component at
the Node level that communicates via the DOWNLOAD_COMMANDS pub/sub topic.
Workers now send StartDownload commands instead of calling the downloader
directly, and receive progress updates through the event-sourced state.

This decouples downloads from the Worker lifecycle and enables future
features like UI-triggered downloads to specific nodes and multi-worker
download sharing.

Test plan:
- Mostly tested in the next PR that adds explicit downloads/deletions to
  the dashboard.
- Started a model that isn't downloaded - it works.
2026-01-23 18:04:09 +00:00

282 lines
8.9 KiB
Python

import multiprocessing as mp
import socket
import time
import typing
import anyio
from fastapi import FastAPI
from fastapi.responses import StreamingResponse
from hypercorn import Config
from hypercorn.asyncio import serve # pyright: ignore[reportUnknownVariableType]
from loguru import logger
from pydantic import BaseModel
from exo.download.impl_shard_downloader import (
build_full_shard,
exo_shard_downloader,
)
from exo.shared.logging import InterceptLogger, logger_setup
from exo.shared.models.model_cards import MODEL_CARDS, ModelId
from exo.shared.types.api import ChatCompletionMessage, ChatCompletionTaskParams
from exo.shared.types.commands import CommandId
from exo.shared.types.common import Host, NodeId
from exo.shared.types.events import Event
from exo.shared.types.tasks import (
ChatCompletion,
ConnectToGroup,
LoadModel,
Shutdown,
StartWarmup,
Task,
)
from exo.shared.types.worker.instances import (
BoundInstance,
Instance,
InstanceId,
MlxJacclInstance,
MlxRingInstance,
)
from exo.shared.types.worker.runners import RunnerId, ShardAssignments
from exo.shared.types.worker.shards import PipelineShardMetadata, TensorShardMetadata
from exo.utils.channels import MpReceiver, MpSender, channel, mp_channel
from exo.utils.info_gatherer.info_gatherer import GatheredInfo, InfoGatherer
from exo.worker.runner.bootstrap import entrypoint
class Tests(BaseModel):
# list[hostname, ip addr]
devs: list[list[str]]
model_id: str
kind: typing.Literal["init", "warmup", "inference"]
mp.set_start_method("spawn", force=True)
logger_setup(None)
async def main():
logger.info("starting cool server majig")
await assert_downloads()
cfg = Config()
cfg.bind = "0.0.0.0:52415"
# nb: shared.logging needs updating if any of this changes
cfg.accesslog = "-"
cfg.errorlog = "-"
cfg.logger_class = InterceptLogger
app = FastAPI()
app.post("/ring")(ring_backend)
app.post("/jaccl")(jaccl_backend)
app.post("/tb_detection")(tb_detection)
shutdown = anyio.Event()
await serve(
app, # type: ignore
cfg,
shutdown_trigger=lambda: shutdown.wait(),
)
await anyio.sleep_forever()
# gracefully shutdown the api
shutdown.set()
async def tb_detection():
send, recv = channel[GatheredInfo]()
ig = InfoGatherer(send)
with anyio.move_on_after(1):
await ig._monitor_system_profiler_thunderbolt_data() # pyright: ignore[reportPrivateUsage]
with recv:
return recv.collect()
async def assert_downloads():
sd = exo_shard_downloader()
# await sd.ensure_shard(await build_full_shard(MODEL_CARDS["qwen3-0.6b"].model_id))
await sd.ensure_shard(
await build_full_shard(MODEL_CARDS["llama-3.1-8b-bf16"].model_id)
)
await sd.ensure_shard(await build_full_shard(MODEL_CARDS["qwen3-30b"].model_id))
await sd.ensure_shard(
await build_full_shard(MODEL_CARDS["gpt-oss-120b-MXFP4-Q8"].model_id)
)
await sd.ensure_shard(
await build_full_shard(MODEL_CARDS["gpt-oss-20b-4bit"].model_id)
)
await sd.ensure_shard(
await build_full_shard(MODEL_CARDS["glm-4.7-8bit-gs32"].model_id)
)
await sd.ensure_shard(
await build_full_shard(MODEL_CARDS["minimax-m2.1-8bit"].model_id)
)
async def ring_backend(test: Tests):
iid = InstanceId(str(hash(str(test.devs))))
weird_hn = socket.gethostname()
for dev in test.devs:
if weird_hn.startswith(dev[0]) or dev[0].startswith(weird_hn):
hn = dev[0]
break
else:
raise ValueError(f"{weird_hn} not in {test.devs}")
return await execute_test(test, ring_instance(test, iid, hn), hn)
def ring_instance(test: Tests, iid: InstanceId, hn: str) -> Instance:
hbn = [Host(ip="i dont care", port=52416) for _ in test.devs]
world_size = len(test.devs)
for i in range(world_size):
if test.devs[i][0] == hn:
hn = test.devs[i][0]
if i - 1 >= 0:
hbn[i - 1] = Host(ip=test.devs[i - 1][1], port=52416)
if i + 1 < len(test.devs):
hbn[i + 1] = Host(ip=test.devs[i + 1][1], port=52416)
hbn[i] = Host(ip="0.0.0.0", port=52416)
break
else:
raise ValueError(f"{hn} not in {test.devs}")
card = MODEL_CARDS[test.model_id]
instance = MlxRingInstance(
instance_id=iid,
ephemeral_port=52416,
hosts_by_node={NodeId(hn): hbn},
shard_assignments=ShardAssignments(
model_id=ModelId(test.model_id),
node_to_runner={NodeId(host[0]): RunnerId(host[0]) for host in test.devs},
runner_to_shard={
RunnerId(test.devs[i][0]): PipelineShardMetadata(
model_card=card,
device_rank=i,
world_size=world_size,
start_layer=(card.n_layers // world_size) * i,
end_layer=min(
card.n_layers, (card.n_layers // world_size) * (i + 1)
),
n_layers=min(card.n_layers, (card.n_layers // world_size) * (i + 1))
- (card.n_layers // world_size) * i,
)
for i in range(world_size)
},
),
)
return instance
async def execute_test(test: Tests, instance: Instance, hn: str):
world_size = len(test.devs)
iid = InstanceId(str(hash(str(test.devs))))
_handle, recv, send = new_runner(instance, hn)
if world_size > 1:
send.send(ConnectToGroup(instance_id=iid))
send.send(LoadModel(instance_id=iid))
match test.kind:
case "init":
pass
case "warmup":
send.send(StartWarmup(instance_id=iid))
case "inference":
send.send(StartWarmup(instance_id=iid))
send.send(
ChatCompletion(
task_params=ChatCompletionTaskParams(
model=test.model_id,
messages=[
ChatCompletionMessage(
role="system", content="You are a helpful assistant"
),
ChatCompletionMessage(
role="user", content="What is the capital of France?"
),
],
),
command_id=CommandId("yo"),
instance_id=iid,
)
)
send.send(Shutdown(runner_id=RunnerId(hn), instance_id=iid))
async def map_recv():
with recv:
try:
async for item in recv:
yield item.model_dump_json() + "\n"
except anyio.ClosedResourceError:
pass
ret = StreamingResponse(map_recv())
ret._pls_dont_gc = _handle # type: ignore
return ret
async def jaccl_backend(test: Tests):
iid = InstanceId(str(hash(str(test.devs))))
weird_hn = socket.gethostname()
for dev in test.devs:
if weird_hn.startswith(dev[0]) or dev[0].startswith(weird_hn):
hn = dev[0]
break
else:
raise ValueError(f"{weird_hn} not in {test.devs}")
return await execute_test(test, jaccl_instance(test, iid), hn)
def jaccl_instance(test: Tests, iid: InstanceId):
card = MODEL_CARDS[test.model_id]
world_size = len(test.devs)
return MlxJacclInstance(
instance_id=iid,
jaccl_devices=[[None, "rdma_en3"], ["rdma_en3", None]],
# rank 0 is always coordinator
jaccl_coordinators={
NodeId(host[0]): test.devs[0][1] + ":52416" for host in test.devs
},
shard_assignments=ShardAssignments(
model_id=ModelId(test.model_id),
node_to_runner={NodeId(host[0]): RunnerId(host[0]) for host in test.devs},
runner_to_shard={
RunnerId(test.devs[i][0]): TensorShardMetadata(
model_card=card,
device_rank=i,
world_size=world_size,
start_layer=card.n_layers,
end_layer=card.n_layers,
n_layers=card.n_layers,
)
for i in range(world_size)
},
),
)
def new_runner(
instance: Instance,
hn: str,
) -> tuple[mp.Process, MpReceiver[Event], MpSender[Task]]:
bound_instance = BoundInstance(
instance=instance, bound_runner_id=RunnerId(hn), bound_node_id=NodeId(hn)
)
ev_send, ev_recv = mp_channel[Event]()
task_send, task_recv = mp_channel[Task]()
runner_process = mp.Process(
target=entrypoint,
args=(
bound_instance,
ev_send,
task_recv,
logger,
),
)
runner_process._pls_dont_gc = (ev_send, task_recv) # type: ignore
runner_process.start()
time.sleep(0.1)
return (runner_process, ev_recv, task_send)
if __name__ == "__main__":
anyio.run(main)