Haskell 当我并行运行大量http请求时，我得到；没有这样的协议名称：tcp“；

代码

mapConcurrently httpLBS requests

投掷

ConnectionFailure Network.BSD.getProtocolByName: does not exist (no such protocol name: tcp))

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在大约1k个请求之后。

所有请求都并行运行，使进程用光了文件描述符。使用

import ClassyPrelude

traverseThrottled :: (MonadMask m, MonadBaseControl IO m, Forall (Pure m), Traversable t) => Int -> (a -> m b) -> t a -> m (t b)
traverseThrottled concLevel action taskContainer = do
    sem <- newQSem concLevel
    let throttledAction = bracket_ (waitQSem sem) (signalQSem sem) . action
    mapConcurrently throttledAction taskContainer

import classyprellude
traversethrotted:：（MonadMask m，MonadBaseControl IO m，Forall（纯m），可遍历t）=>Int->（a->mb）->ta->m（tb）
Traversethrotted ConclLevel操作taskContainer=do
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