Hello, On Fri, 20 May 2016 00:11:02 +0000 David Turner wrote: > You can also mount the rbd with the discard option. It works the same > way as you would mount an ssd to free up the space when you delete > things. I use the discard option on my ext4 rbds on Ubuntu and it frees > up the used Ceph space immediately. > While that certainly works (and has the advantage of being fully automatic and not needing any human or CRON intervention), it has a big disadvantage as well. With normal storage (SSDs) the consensus already is that manual fstrim at a time of low utilization is preferable, since TRIM activity can slow down things as the SSD does its housekeeping. With Ceph this is even more pronounced (TRIM'ing RBD images is quite costly in terms of IO, IOPS), so doing TRIMs only when actually needed and during quite times is much preferred. Regards, Christian > Sent from my iPhone > > On May 19, 2016, at 12:30 PM, Albert Archer > <albertarcher94@xxxxxxxxx<mailto:albertarcher94@xxxxxxxxx>> wrote: > > Thank you for your great support . > > Best Regards > Albert > > On Thu, May 19, 2016 at 10:41 PM, Udo Lembke > <ulembke@xxxxxxxxxxxx<mailto:ulembke@xxxxxxxxxxxx>> wrote: Hi Albert, > to free unused space you must enable trim (or do an fstrim) in the vm - > and all things in the storage chain must support this. The normal > virtio-driver don't support trim, but if you use scsi-disks with > virtio-scsi-driver you can use it. Work well but need some time for huge > filesystems. > > Udo > > > On 19.05.2016 19:58, Albert Archer wrote: > Hello All. > I am newbie in ceph. and i use jewel release for testing purpose. it > seems every thing is OK, HEALTH_OK , all of OSDs are in UP and IN state. > I create some RBD images (rbd create .... ) and map to some ubuntu > host . > I can read and write data to my volume , but when i delete some content > from volume (e,g some huge files,...), populated capacity of cluster > does not free and None of objects were clean. > what is the problem ??? > > Regards > [https://ssl.gstatic.com/ui/v1/icons/mail/images/cleardot.gif]Albert > > > > _______________________________________________ > ceph-users mailing list > ceph-users@xxxxxxxxxxxxxx<mailto:ceph-users@xxxxxxxxxxxxxx> > http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com > > > > _______________________________________________ > ceph-users mailing list > ceph-users@xxxxxxxxxxxxxx<mailto:ceph-users@xxxxxxxxxxxxxx> > http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com -- Christian Balzer Network/Systems Engineer chibi@xxxxxxx Global OnLine Japan/Rakuten Communications http://www.gol.com/ _______________________________________________ ceph-users mailing list ceph-users@xxxxxxxxxxxxxx http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
![https://ssl.gstatic.com/ui/v1/icons/mail/images/cleardot.gif]Albert](https://ssl.gstatic.com/ui/v1/icons/mail/images/cleardot.gif]Albert){kind=link}
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