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
A female Aedes mosquito gets infected with the Dengue virus when it bites a person infected with dengue. It then transmits dengue to other healthy individuals it goes on to bite.
Help to break the dengue transmission cycle!
✅ Everyone should use insect repellent and carry out other S-A-W actions to protect themselves from being bitten by mosquitoes.
✅ Those diagnosed with or suspected to be infected with dengue are also advised to avoid further mosquito bites, to prevent passing on the Dengue virus to mosquitoes and other people in their neighbourhoods.
S-A-W:
✅ Spray insecticide in dark corners around the house
✅ Apply insect repellent regularly
✅ Wear long-sleeve tops and long pants
📱 Download the myENV app to receive alerts on high Aedes mosquito populations near you, or visit go.gov.sg/dengue-high-risk
#DenguePrevention
Heading out for holiday adventures? Before you dash, don’t give the mozzies any room to stay!
Follow the B-L-O-C-K steps and mozzie-proof your home before you roam:
✅ Break up hardened soil
✅ Lift and empty flowerpot plates
✅ Overturn pails and wipe their rims
✅ Change water in vases
✅ Keep roof gutters clear and place BTI insecticide
Let’s make this holiday season not only merry but also mindful.
#BLOCKDengue#DenguePrevention
Going on your festive holiday escapade? 🏖
Give the mozzies no room to stay! Follow the B-L-O-C-K steps and mozzie-proof your home before you roam:
✅ Break up hardened soil
✅ Lift and empty flowerpot plates
✅ Overturn pails and wipe their rims
✅ Change water in vases
✅ Keep roof gutters clear and place BTI insecticide
Together, we can keep dengue at bay. Learn more: https://go.gov.sg/mozzieproof
#BLOCKDengue#DenguePrevention
#SGDengueUpdate The number of active dengue clusters reported continues to remain high, with 64 active clusters reported as of 28 Dec. 198 dengue cases were reported in the week ending 26 Dec, and the cumulative number of dengue cases for this year stands at more than 35,100.
Let’s keep up our #DenguePrevention efforts and continue doing the #MozzieWipeout at least once a week. Find out what else you can do to protect yourself and your family at go.gov.sg/mozzieproof
#SGDengueUpdate As of 17 Dec 2020, there have been 34,844 reported dengue cases this year, with 228 cases reported last week. While NEA has closed about 98% of the dengue clusters notified since the beginning of 2020, there are still over 230 residential areas with high Aedes aegypti mosquito population currently.
So let’s stay vigilant and keep up our #DenguePrevention efforts. If you’re planning to go for a staycation, don’t forget to do the #MozzieWipeout first! Learn more: go.gov.sg/mozzieproof
🦟They’re small, they’re pesky, and they’re definitely not welcome! Mosquitoes love stagnant water - don’t let them crash the party.
It’s time for a Real-World Quest! Carry out the #BLOCKdengue steps at least once a week and mozzie-proof your home:
✅ Break up hardened soil
✅ Lift and empty flowerpot plates
✅ Overturn pails and wipe their rims
✅ Change water in vases
✅ Keep roof gutters clear and place BTI insecticide
#DenguePrevention#Minecraft
Don't let your home become the Upside Down for mozzies! 🦟
The #BLOCKdengue steps are your weekly defence against these tiny monsters. Do these at least once a week:
✅ Break up hardened soil
✅ Lift and empty flowerpot plates
✅ Overturn pails and wipe their rims
✅ Change water in vases
✅ Keep roof gutters clear and add BTI insecticide
#DenguePrevention#StrangerThings