$ sudo du -h -d 0 home/ 309G home/ $ df -h Filesystem Size Used Avail Use% Mounted on ... /dev/sda4 550G 309G 214G 60% /home ... System Monitor on Ubuntu shows the used space on /home is 331.1 GB
Do the different ways measure the same thing?
How differently do they make the measurements?
Thanks.
It is two different units. The larger number is in gigabytes. 1 gigabyte = 1 billion bytes. The smaller number is in gibibytes. 1 gibibyte = 1,073,741,824 bytes = 2^30 bytes
It's the same measurement. 309 Gb is the size specified in powers of 2 (the ugly-named Gibibyte), while 331 Gb is the size specified in powers of 10 according to the SI (Gigabyte).
309 Gb (in powers of 2) * 1024 * 1024 * 1024 = 331786223616 bytes i.e. 331 Gb (in powers of 10).
As pointed out by @don_crissti, df -h prints values in binary powers. If you had run df -H, which uses decimal powers instead, it would have printed 331 Gb of used space.
For more information, see https://en.wikipedia.org/wiki/Binary_prefix .
