The file system isn't aware of the deduplication that occurs underneath. All it sees a physical disk. For example you can write zeros to a file and fill up the3.4TB filesystem, but the Vdisk deduplication would mean only a few MB or GB is used on the actual physical disk.
https://groups.google.com/forum/#!topic/quadstor-virt/QQUCkhhsAYk is a similar topic On Fri, Oct 21, 2016 at 10:21 PM, Aleksey Maksimov <aleksey.i.maksi...@gmail.com> wrote: > Hello QUADStor guru`s! > > > Fresh installed QUADStor 3.2.10 > > I have created and mounted the virtual disk as ext4 partition. > Then I exported this partition using NFSv4 > Then I started from NFS-client backup of KVM (oVirt) virtual machines in > NFS-share > > VDisk Statisics from QUADStor web-console: > > Write Size: 33.85 GB > Write Ops: 231954 > Read Size: 23.86 MB > Read Ops: 4797 > Unaligned Size: 0.00 KB > Data Deduped: 27.11 GB > Dedupe Ratio: 5.020 > Data Unmapped: 3.638 TB > Unmap Ops: 1907200 > Blocks Zeroed: 0.00 KB > Uncompressed Size: 6.74 GB > Compressed Size: 0.00 KB > > Based on these statistics, I expect to see what's disc used space is 6.74 > GB, but in fact here is what I see: > > # df -lah /mnt/quadstor-vv1 > > Filesystem Size Used Avail Use% Mounted on > /dev/sdu 3.6T 32G 3.4T 1% /mnt/quadstor-vv1 > > # du -shc /mnt/quadstor-vv1/* > > 16K /mnt/quadstor-vv1/lost+found > 4.0K /mnt/quadstor-vv1/ovirt-engine-backup > 3.8G /mnt/quadstor-vv1/ovirt-iso-domain > 29G /mnt/quadstor-vv1/ovirt-vm-backup > 32G total > > Statistics about deduplication deceptive? > Deduplication doesn't really work or I don't understand something? > > -- > You received this message because you are subscribed to the Google Groups > "QUADStor Storage Virtualization" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to quadstor-virt+unsubscr...@googlegroups.com. > For more options, visit https://groups.google.com/d/optout. -- You received this message because you are subscribed to the Google Groups "QUADStor Storage Virtualization" group. To unsubscribe from this group and stop receiving emails from it, send an email to quadstor-virt+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
