在Hadoop MR(主要是民盟)中,是否有可能以同步/空中的方式从属于单一工作的两名地图绘制到同一档案中?
另外,还写给两台按序列顺序从事不同工作的地图绘制的单一档案?
在其他档案系统中也有烟雾。 克民盟的机制是什么?
Hadoop地图任务之间没有沟通,因此不可能在地图任务之间保持某种同步。
《人类发展报告》中的文件可由一位作者撰写,而许多读者可以阅读。
I think MapR allows multiple writers to the same file.
日 本书必须附在尾,任何任意抵消也不可能改动。
Just curious, what is the use case for multiple map tasks writing to a single file?
Set the number or reducers = 1 (mapred.reduce.tasks=1)
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