Недавно делал быстрый прототип асинхронного приложения в котором требовалось вызывать много синхронного кода. Да, я знаю, что это не лучший дизайн, но нужно было быстрое решение на один процесс и без очередей. Поэтому я выполнял код в потоках.
Выглядело это примерно так:
from fastapi.concurrency import run_in_threadpool
async def execute(data: DataRequest) -> DataResponse:
try:
result = await run_in_threadpool(sync_function, data)
return DataResponse(data=result)
except Exception as e:
return DataResponse(
error=str(e),
success=False,
)
В общем работает нормально. Для всех вызовов под капотом используется общий тредпул, всё работает предсказуемо.
Но потребовалось изменить количество запускаемых в пуле потоков (по умолчанию создается 40 воркеров).
Так как дело происходит с FastAPI, делается это через lifespan используя настройки anyio:
import anyio
@asynccontextmanager
async def lifespan(app: FastAPI):
limiter = anyio.to_thread.current_default_thread_limiter()
limiter.total_tokens = 100
yield
# если вдруг нужно вернуть обратно
limiter.total_tokens = 40
Зачем менять количество воркеров?
- уменьшить, если оперативки мало (один тред занимает ~8мб)
- увеличить чтобы выдержать нагрузку
Если есть предложения получше при тех же вводных - предлагайте😉
#async
🪐 In the galaxy dubbed "The Whale" (NGC 4631), astronomers have detected a barrage of fast radio bursts—ultra-brief, intense flashes of radio energy—coming not from the center, but from the galaxy’s outer regions. These mysterious signals last just milliseconds but shine as brightly as billions of suns, making NGC 4631's outskirts a surprising hotspot for one of space’s most powerful, fleeting phenomena. ✨
#fastbursts⚡#galaxies⚡#radioastronomy⚡#nasa⚡#galaxy⚡#stars⚡#astronomy⚡#universe⚡#cosmos⚡#space
👉subscribe Universe Mysteries
🪐 In 2024, astronomers used the CHIME radio telescope to spot FRB 20240117A, a fast radio burst coming from a galaxy nearly 4 billion light-years away in the constellation Lynx. This single millisecond flash released more energy than the Sun does in several days, showing just how powerful these mysterious cosmic radio signals can be—even when they travel billions of light-years through silent, near-empty space. ✨
#frb⚡#galaxies⚡#radioastronomy⚡#nasa⚡#galaxy⚡#stars⚡#astronomy⚡#universe⚡#cosmos⚡#space
👉subscribe Universe Mysteries
👉more Channels
🪐 Between 1960 and 1998, the Arecibo radio telescope in Puerto Rico transmitted several powerful messages toward star clusters like M13 in the hope that intelligent aliens, if they exist, might detect and respond. These "active SETI" attempts used coded radio signals aimed at real star systems—making the search for extraterrestrial life not just a matter of listening, but also of sending greetings out into the galaxy with real, named astronomical targets. ✨
#aliens⚡#SETI⚡#radioastronomy⚡#nasa⚡#galaxy⚡#stars⚡#astronomy⚡#universe⚡#cosmos⚡#space
👉subscribe Universe Mysteries
👉more Channels
🪐 In the constellation Dorado, the massive galaxy NGC 1316 bears the scars of cosmic collisions—its shell-like structures and tangled lanes of dust betray a history of devouring smaller galaxies. Radio observations have revealed that this turbulent giant also hosts powerful jets and lobes fueled by a hidden supermassive black hole at its core, making NGC 1316 a remarkable blend of chaos and creation in the southern sky. ✨
#galaxy⚡#mergers⚡#radioastronomy⚡#blackhole⚡#nasa⚡#stars⚡#astronomy⚡#universe⚡#cosmos⚡#space
👉subscribe Universe Mysteries
🪐 In 2024, observations with the CHIME radio telescope revealed that some fast radio bursts (FRBs) can travel through the sparse gas between galaxies—known as the intergalactic medium—without slowing down or scattering as much as expected. This suggests that the space between galaxies, like that between the Milky Way and the Triangulum Galaxy (M33), is even more empty and calm than scientists previously thought, allowing these intense millisecond bursts of radio energy to arrive at Earth almost untouched by cosmic matter. ✨
#FRB⚡#radioastronomy⚡#intergalactic⚡#nasa⚡#galaxy⚡#stars⚡#astronomy⚡#universe⚡#cosmos⚡#space
👉subscribe Universe Mysteries
👉more Channels
🪐 Among the strangest discoveries in astronomy are fast radio bursts (FRBs) emerging from the spiral galaxy NGC 253, also known as the Sculptor Galaxy. In 2022, scientists detected a repeating FRB source here—brief flashes of radio energy lasting just milliseconds and releasing more power than the Sun generates in years—making NGC 253 a new hot spot in the ongoing quest to understand these mysterious cosmic signals. ✨
#fastbursts⚡#sculptorgalaxy⚡#radioastronomy⚡#nasa⚡#galaxy⚡#stars⚡#astronomy⚡#universe⚡#cosmos⚡#space
👉subscribe Universe Mysteries
👉more Channels