Disk space economy

[Janos Dohanics]

Hello List,

I have a directory which contains 48 files. 35 of these files are
large, close to 2 GB (reported by ls -l). 7 of the files a smaller than
4 K, the rest of the files are few dozen Ks in size.

This is a FreeBSD 10 system with ZFS and RAIDZ2.

du -h reports the directory to be 208G.

du -A -h reports the directory to be 69G.

It seems there is 2G wasted for each 1G stored data - would you explain
why and what can I do make more economical use of disk space?

-- 
Janos Dohanics