Re: [zfs-discuss] compressed fs taking up more space than uncompressed equivalent
2009/10/23 Gaëtan Lehmann : > > Le 23 oct. 09 à 08:46, Stathis Kamperis a écrit : > >> 2009/10/23 michael schuster : >>> >>> 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
Re: [zfs-discuss] compressed fs taking up more space than uncompressed equivalent
Le 23 oct. 09 à 08:46, Stathis Kamperis a écrit : 2009/10/23 michael schuster : 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. Regards, Gaëtan -- Gaëtan Lehmann Biologie du Développement et de la Reproduction INRA de Jouy-en-Josas (France) tel: +33 1 34 65 29 66fax: 01 34 65 29 09 http://voxel.jouy.inra.fr http://www.itk.org http://www.mandriva.org http://www.bepo.fr PGP.sig Description: Ceci est une signature électronique PGP ___ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
Re: [zfs-discuss] compressed fs taking up more space than uncompressed equivalent
Stathis Kamperis wrote: 2009/10/23 michael schuster : 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 obvious, but still: you did make sure that the compressed one doesn't have any other data lying around, right? - how do you copy? With cp(1). Should I be using zfs send | zfs receive ? I don't know :-) I was just (still am) thinking out loud. - is the other FS also ZFS? Yes. And they both live under the same pool. If it matters, I don't have any snapshots on neither of the filesystems. "zfs list -t all" might still be revealing ... Michael -- Michael Schuster http://blogs.sun.com/recursion Recursion, n.: see 'Recursion' ___ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
Re: [zfs-discuss] compressed fs taking up more space than uncompressed equivalent
2009/10/23 michael schuster : > 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 > - how do you copy? With cp(1). Should I be using zfs send | zfs receive ? > - is the other FS also ZFS? Yes. And they both live under the same pool. If it matters, I don't have any snapshots on neither of the filesystems. Thank you for your time. Best regards, Stathis Kamperis ___ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
Re: [zfs-discuss] compressed fs taking up more space than uncompressed equivalent
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? - how do you copy? - is the other FS also ZFS? Michael -- Michael Schuster http://blogs.sun.com/recursion Recursion, n.: see 'Recursion' ___ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
[zfs-discuss] compressed fs taking up more space than uncompressed equivalent
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 ? Best regards, Stathis ___ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
