ZFS stats output - used, compressed, deduped, etc.

[Jason Usher]

Hi,

I have a ZFS filesystem with compression turned on.  Does the "used" property show me the actual data size, or the compressed data size ?  If it shows me the compressed size, where can I see the actual data size ?

I also wonder about checking status of dedupe - I created my pool without dedupe, and continue to NOT enable dedupe - from zpool history, we see:

zpool create -f -O atime=off -O setuid=off -O exec=off -m /mnt/pool pool raidz3 da0 da1 da2 da3 da4 da5 da6 da7 da8 da9 da10 da11

Later, I enabled dedup for just a single filesystem on this pool:

zfs set dedup=on pool/dataset

and now, I see in 'zpool list' a value for dedupratio:

pool  dedupratio     1.65x       -


Why do I see a value here ?  Isn't dedupe still OFF for the pool as a whole ?  I do NOT want to enable dedupe for the entire pool.

Also, why do I not see any dedupe stats for the individual filesystem ?  I see compressratio, and I see dedup=on, but I don't see any dedupratio for the filesystem itself...

Did turning on dedupe for a single filesystem turn it on for the entire pool ?