Kylin history job building directories can not be deleted by StorageCleanupJob

[liushaohui]

Hi all,

In our production kylin cluster, we found that Kylin history job 
building  directories can not be deleted by the StorageCleanupJob.

After checking the code,  we found that the StorageCleanupJob will 
remove every segment working dir from deletion list. See 
StorageCleanupJob.java#156

That means job building directories belongs to cube segments will be 
deleted for ever.

But the directory: cuboid under each job building directory usually use 
a lot storage space.

I don't know why ? Maybe there is some wrong configurations.

Thanks for any tips or suggestions~

Thanks

-Shaohui Liu from XIAOMI