files take up twice their size - so disk nearly full

WD External and Portable SSD
1

I am using a new WD Elements SSD 1Tb external disk on Ubuntu linux.

After writing about 340 Gb of data onto the disk applications are reporting just over twice that being used, e.g. command ‘df -lh’ reports 792G used, and therefore only 140G available, GParted does the same.

so these show there is very little space left on the disk.

i also notice that directories are much greater in the copy than in the original, their files are the same size as each other but the directories’ properties show they are larger

are there any ways to correct this, or is it a faulty disk?

2

Hi @ruthtoby, this might not be a faulty disk. On Linux, higher disk usage than expected can often be due to:

  1. File system overhead or sparse file expansion – especially if copying from ext4 to another format.
  2. Hidden files or hard links – use du -sh * and du -sch in the root of the drive to check actual space used.
  3. Symbolic links getting copied as actual files – if you used cp -r or similar, symlinks may have become full copies.
  4. Large block sizes – can make many small files take up more space.

You can also try ncdu for a more visual breakdown of usage.

3

hi @helly
thanks. In the end i reformatted the disc, and it works just find. I deleted all the data off first, don’t know if this is what helped.