Is there a way to quickly get an accurate size for a directory (including, recursively, all its sub-directories)? I don't want the sizes of the subdirs, I just mean that they should be recursively included in the total size reported.
Failing that, a way to get an approximate size? I am thinking something along the lines of
df that produces a quick response for the entire file system, but this time for a specific directory (and it's subdirectories).
du seem to take ages when given a directory contains thousands of sub-dirs.