与 uvloop 等效的异步事件循环

Question

我有一个使用 asyncio 的协程方法的事件循环。

我热衷于使用uvloop 寻找以下示例的等效项。

这是一个简单的asyncio 事件循环示例：

import asyncio

async def read(**kwargs):
    oid = kwargs.get('oid', '0.0.0.0.0.0')
    time = kwargs.get('time', 1)
    try:
        print('start: ' + oid)
    except Exception as exc:
        print(exc)
    finally:
        await asyncio.sleep(time)
        print('terminate: ' + oid)


def event_loop(configs):
    loop = asyncio.get_event_loop()

    for conf in configs:
        asyncio.ensure_future(read(oid=conf['oid'], time=conf['time']))

    return loop

if __name__ == '__main__':
    snmp_configurations = [
        {'time': 5, 'oid': '1.3.6.3.2.4'},
        {'time': 6, 'oid': '1.3.6.3.5.8'},
    ]  # TODO :: DUMMY
    loop = event_loop(snmp_configurations)
    try:
        loop.run_forever()
    except KeyboardInterrupt:
        pass
    finally:
        print("Closing Loop")
        loop.close()

---

问题：

• 如何改用uvloop上面的sn-p代码？

• 以下更改对于使用具有更高性能的uvloop 是否正确？

  import uvloop
  
  def event_loop(configs):
      asyncio.set_event_loop_policy(uvloop.EventLoopPolicy())  # TODO  :: uvloop.
      loop = asyncio.get_event_loop()
  
   `   for conf in configs:
          asyncio.ensure_future(read(oid=conf['oid'], time=conf['time']))
  
      return loop
  

---

[注意]：

• uvloop 声称使 asyncio 速度提高了 2-4 倍。

Answer 1

在调用asyncio.get_event_loop()之前设置事件循环策略。

import asyncio
import uvloop
asyncio.set_event_loop_policy(uvloop.EventLoopPolicy())

async def read(**kwargs):
    oid = kwargs.get('oid', '0.0.0.0.0.0')
    time = kwargs.get('time', 1)
    try:
        print('start: ' + oid)
    except Exception as exc:
        print(exc)
    finally:
        await asyncio.sleep(time)
        print('terminate: ' + oid)


def event_loop(configs):
    loop = asyncio.get_event_loop()

    for conf in configs:
        asyncio.ensure_future(read(oid=conf['oid'], time=conf['time']))

    return loop

if __name__ == '__main__':
    snmp_configurations = [
        {'time': 5, 'oid': '1.3.6.3.2.4'},
        {'time': 6, 'oid': '1.3.6.3.5.8'},
    ]  # TODO :: DUMMY
    loop = event_loop(snmp_configurations)
    try:
        loop.run_forever()
    except KeyboardInterrupt:
        pass
    finally:
        print("Closing Loop")
        loop.close()

是的，这段代码是正确的。您可以在导入后设置事件循环策略。

import uvloop
import asyncio
asyncio.set_event_loop_policy(uvloop.EventLoopPolicy())  # TODO  :: uvloop.

def event_loop(configs):

    loop = asyncio.get_event_loop()

    for conf in configs:
        asyncio.ensure_future(read(oid=conf['oid'], time=conf['time']))

    return loop