Thanks for the tip! On 9/12/19 3:03 PM, Robert Trevellyan wrote: > Your TL;DR: for ashift refers to ZFS record size, but ashift > determines block size (smallest I/O, with 12 meaning 4096 bytes to > match common modern hard drive sector size), not record size. > > Robert Trevellyan > > > On Thu, Sep 12, 2019 at 8:22 AM Alwyn Kik <al...@proteon.com > <mailto:al...@proteon.com>> wrote: > > I did some research for this a while ago, and currently use the > following setup: > https://gist.github.com/Alveel/c8e80aeef208a7e27c9bd50d0023420c Of > course this is still far from perfect, and I welcome more ideas or > criticism, but perhaps it can help you out :) > > On 9/11/19 10:03 PM, Carl Soderstrom wrote: > >> On 09/11 09:40 , Alexander Moisseev via BackupPC-users wrote: >>> On 11.09.2019 18:19, Robert Trevellyan wrote: >>>> I'm letting ZFS do the compression (using the default of LZ4) with >>>> BackupPC handling deduplication. I think you'll find a reasonable >>>> consensus that ZFS compression is always a win for storage space (it will >>>> store un-compressible data unmodified), whereas ZFS deduplication is best >>>> avoided in most cases, mostly due to its high memory usage. It's possible >>>> that BackupPC compression would be tighter than LZ4, >>> Actually, on ZFS you are not limited to LZ4, but in ZFS each file block >>> is compressed independently, that is why in most cases BackupPC compression >>> is higher, though it depends on data. >>> >>> We moved from 77.96G cpool to pool on compressed filesystem recently. >>> Now it consumes 81.2G, so there is not much difference. >>> >>> # zfs get compression,compressratio,recordsize,referenced zroot/bpc/pool >>> NAME PROPERTY VALUE SOURCE >>> zroot/bpc/pool compression gzip-3 local >>> zroot/bpc/pool compressratio 3.87x - >>> zroot/bpc/pool recordsize 128K default >>> zroot/bpc/pool referenced 81,2G - >> Thanks Alexander, those details are really helpful. >> > -- > Alwyn > > _______________________________________________ > BackupPC-users mailing list > BackupPC-users@lists.sourceforge.net > <mailto:BackupPC-users@lists.sourceforge.net> > List: https://lists.sourceforge.net/lists/listinfo/backuppc-users > Wiki: http://backuppc.wiki.sourceforge.net > Project: http://backuppc.sourceforge.net/ > > > > _______________________________________________ > BackupPC-users mailing list > BackupPC-users@lists.sourceforge.net > List: https://lists.sourceforge.net/lists/listinfo/backuppc-users > Wiki: http://backuppc.wiki.sourceforge.net > Project: http://backuppc.sourceforge.net/
-- A. Kik
_______________________________________________ BackupPC-users mailing list BackupPC-users@lists.sourceforge.net List: https://lists.sourceforge.net/lists/listinfo/backuppc-users Wiki: http://backuppc.wiki.sourceforge.net Project: http://backuppc.sourceforge.net/
