问题描述：
使用云主机测试Flink时，根目录满了。 经排查发现运行Flink任务后根目录空间一直在减少，最后定位持续增加的目录是/tmp目录
解决方法：
修改Flink配置使用一个相对较大的磁盘目录做为Flink运行时目录
Override the directories for temporary files. If not specified, the
system-specific Java temporary directory (java.io.tmpdir property) is taken.
For framework setups on Yarn, Flink will automatically pick up the
containers' temp directories without any need for configuration.
Add a delimited list for multiple directories, using the system directory
delimiter (colon ':' on unix) or a comma, e.g.:
/data1/tmp:/data2/tmp:/data3/tmp
Note: Each directory entry is read from and written to by a different I/O
thread. You can include the same directory multiple times in order to create
multiple I/O threads against that directory. This is for example relevant for
high-throughput RAIDs.
io.tmp.dirs: /dev/shm/tmp
问题解决