[Jiaz]

Log shows that JDownloader/Java hangs on parsing your fstab/mounts.

at sun.nio.fs.UnixNativeDispatcher.stat0(Native Method)
at sun.nio.fs.UnixNativeDispatcher.stat(UnixNativeDispatcher.java:286)
at sun.nio.fs.UnixFileAttributes.get(UnixFileAttributes.java:70)
at sun.nio.fs.UnixFileStore.devFor(UnixFileStore.java:55)
at sun.nio.fs.UnixFileStore.<init>(UnixFileStore.java:70)
at sun.nio.fs.LinuxFileStore.<init>(LinuxFileStore.java:48)
at sun.nio.fs.LinuxFileSystem.getFileStore(LinuxFileSystem.java:112)
at sun.nio.fs.UnixFileSystem$FileStoreIterator.readNext(UnixFileSystem.java:213)
at sun.nio.fs.UnixFileSystem$FileStoreIterator.hasNext(UnixFileSystem.java:224)

Please check it for invalid/broken entries