How / when is disk usage calculated?

[ThinIce]

Hi all

How / when / by what process is the disk usage of an account calculated? du -h returns a different value (by a 100mb plus) than what is reported in WHM / users Cpanel. This will display correctly if the .cpanel-ducache file is removed (after about 15 mins I believe?) but then does not seem to be updated correctly as time goes by.

I ran fixquotas during the week so bit confused on this one.

TIA

 

[ThinIce]

Ah - searching around I've found that incremental backups are counted under disk usage - so the du -h wouldn't be correct on the home directory. Am I correct this is the case?