什么是hadoop.tmp.dir？ [英] What should be hadoop.tmp.dir ?

问题描述

Hadoop的配置参数 hadoop.tmp.dir ，根据文档，它是`其他临时目录的基础。 I假设，这个路径指的是本地文件系统。

我把这个值设置为 / mnt / hadoop -tmp / hadoop - $ {user.name } 。格式化namenode并启动所有服务之后，我在HDFS上看到完全相同的路径。

这是否意味着， hadoop.tmp.dir 是指 HDFS ？

解决方案

这很令人困惑，但 hadoop.tmp.dir code>用作本地临时目录的基础，也用于 HDFS 。该文件不是很好，但默认情况下 mapred.system.dir 设置为$ {hadoop.tmp.dir} / mapred / system ，并在HDFS 上定义了Map / Reduce框架存储系统文件的路径。

如果你不想把它们绑定在一起，你可以编辑你的 mapred-site.xml ，这样mapred.system.dir的定义就不会与 $ {hadoop.tmp.dir}

Hadoop has configuration parameter hadoop.tmp.dir which, as per documentation, is `"A base for other temporary directories." I presume, this path refers to local file system.

I set this value to /mnt/hadoop-tmp/hadoop-${user.name}. After formatting the namenode and starting all services, I see exactly same path created on HDFS.

Does this mean, hadoop.tmp.dir refers to temporary location on HDFS?

解决方案

It's confusing, but hadoop.tmp.dir is used as the base for temporary directories locally, and also in HDFS. The document isn't great, but mapred.system.dir is set by default to "${hadoop.tmp.dir}/mapred/system", and this defines the Path on the HDFS where where the Map/Reduce framework stores system files.

If you want these to not be tied together, you can edit your mapred-site.xml such that the definition of mapred.system.dir is something that's not tied to ${hadoop.tmp.dir}

这篇关于什么是hadoop.tmp.dir？的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！