PLINQ performs best when it is allowed to process elements in the source collection in any order, and pass them to the next operator as soon as they are ready.

如果允许按任意顺序处理源集合中的元素，并在这些元素就绪时立即将它们传递到下一个运算符，则PLINQ的性能最佳。

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Another click, the voice states you have reached the head of the queue, your call will be answered as soon as the next operator becomes available.

BBC: THE UNANSWERED CALL

"We think the government should ensure that rolling stock is commissioned now for the next franchise operator to take over, " he said.

BBC: Shropshire to London trains: New service planned

Nokia is passing up U.S. holiday sales for its Windows Phone handsets in hopes of introducing them with strong operator backing next year.

FORBES: Last Call: Can Nokia Compete With Apple And Android?