we use a NAS to archive stream from database to files. If we look at the file size on disk, it is bigger than expected.

For example : 

File size is 127K

ls -alh | grep write-chupmb-pdf
127K 2020-07-02 10:43 write-chupmb-pdf

Size on disk  is 192K

du -sh * | grep write-chupmb-pdf
192K    write-chupmb-pdf

Or expected size is 128K (with 4K blocs)

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