Forgive me found this post which solved my issue: https://www.sebastien-han.fr/blog/2015/02/02/openstack-and-ceph-rbd-discard/ On Mon, Jul 23, 2018 at 11:22 PM, Satish Patel <satish.txt@xxxxxxxxx> wrote: > I have same issue, i just build new Ceph cluster for my Openstack VMs > workload using rbd and i have created bunch of VM did some dd test to > create big big file to test performance now i deleted all dd file but > ceph still showing USED space. > > I tried to do from guest VM > > [root@c7-vm ~]# sudo fstrim / > fstrim: /: the discard operation is not supported > > > Can we run fstrim on ceph OSD node? what if i delete my VM in that > case how do i run fstrim ? > > On Mon, Jul 23, 2018 at 6:13 PM, Ronny Aasen <ronny+ceph-users@xxxxxxxx> wrote: >> On 23.07.2018 22:18, Sean Bolding wrote: >> >> I have XenServers that connect via iSCSI to Ceph gateway servers that use >> lrbd and targetcli. On my ceph cluster the RBD images I create are used as >> storage repositories in Xenserver for the virtual machine vdisks. >> >> >> >> Whenever I delete a virtual machine, XenServer shows that the repository >> size has decreased. This also happens when I mount a virtual drive in >> Xenserver as a virtual drive in a Windows guest. If I delete a large file, >> such as an exported VM, it shows as deleted and space available. However; >> when check in Ceph using ceph –s or ceph df it still shows the space being >> used. >> >> >> >> I checked everywhere and it seems there was a reference to it here >> https://github.com/ceph/ceph/pull/14727 but not sure if a way to trim or >> discard freed blocks was ever implemented. >> >> >> >> The only way I have found is to play musical chairs and move the VMs to >> different repositories and then completely remove the old RBD images in >> ceph. This is not exactly easy to do. >> >> >> >> Is there a way to reclaim free space on RBD images that use Bluestore????? >> What commands do I use and where do I use this from? If such command exist >> do I run them on the ceph cluster or do I run them from XenServer? Please >> help. >> >> >> >> >> >> Sean >> >> >> >> >> >> >> >> >> I am not familiar with Xen, but it does sounds like you have a rbd mounted >> with a filesystem on the xen server. >> in that case it is the same as for other filesystems. Deleted files are just >> deleted in the file allocation table, and the RBD space is "reclaimed" when >> the filesystem zeroes out the now unused blocks. >> >> in many filesystems you would run the fstrim command to overwrite free'd >> blocks with zeroes, optionally mount the fs with the the discard option. >> in xenserver >6.5 this should be a button in xencenter to reclaim freed >> space. >> >> >> kind regards >> Ronny Aasen >> >> _______________________________________________ >> ceph-users mailing list >> ceph-users@xxxxxxxxxxxxxx >> http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com >> _______________________________________________ ceph-users mailing list ceph-users@xxxxxxxxxxxxxx http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
 |