2009/10/23 Gaëtan Lehmann <gaetan.lehm...@jouy.inra.fr>: > > Le 23 oct. 09 à 08:46, Stathis Kamperis a écrit : > >> 2009/10/23 michael schuster <michael.schus...@sun.com>: >>> >>> Stathis Kamperis wrote: >>>> >>>> Salute. >>>> >>>> I have a filesystem where I store various source repositories (cvs + >>>> git). I have compression enabled on and zfs get compressratio reports >>>> 1.46x. When I copy all the stuff to another filesystem without >>>> compression, the data take up _less_ space (3.5GB vs 2.5GB). How's >>>> that possible ? >>> >>> just a few thoughts: >>> - how do you measure how much space your data consumes? >> >> With zfs list, under the 'USED' column. du(1) gives the same results >> as well (the individual fs sizes aren't enterily identical with those >> that zfs list reports , but the difference still exists). >> >> tank/sources 3.73G 620G 3.73G /export/sources >> <--- compressed >> tank/test 2.32G 620G 2.32G /tank/test >> <--- uncompressed >> > > USED includes the size of the children and the size of the snapshot. I see > below that you don't have snapshots on that pull, but in general, I found > more useful to use > > zfs list -o space,compress,ratio > > to look at how the space is used. > >>> - how do you copy? >> >> With cp(1). Should I be using zfs send | zfs receive ? > > zfs send/receive or rsync -aH may do a better job by preserving hard links.
I destroyed the test fs, recreated it and did an rsync. The size of the uncompressed filesystem is now larger than the compressed one. I guess cp(1) missed a great deal of stuff, which is weird because I didn't get any error/warning on the console output. All good now. Thanks Gaëtan and Michael for your time and sorry to the rest of the list readers for the noise. Best regards, Stathis Kamperis _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
