Gregory Farnum writes:
> On Tue, Mar 7, 2017 at 12:43 PM, Kent Borg <[email protected]> wrote:
>> I would love it if someone could toss out some examples of the sorts
>> of things snapshots are good for and the sorts of things they are
>> terrible for.  (And some hints as to why, please.)

> They're good for CephFS snapshots. They're good at RBD snapshots as
> long as you don't take them too frequently.

We take snapshots of about thirty 2-TB RBD images (Ceph Cinder volumes)
every night.  We keep about 60 of each around.  Does that still fall
under "reasonable"?

One round of snapshots is deleted every night; that causes significant
load on our cluster - currently Hammer, will be upgraded to Jewel soon.

Most of the volumes (and thus snapshots) don't have the "object-map"
feature enabled yet; maybe after the Jewel upgrade we can add
object-maps to them to reduce the cost of deleting the snapshots.

Do object-maps help with snap trimming, or am I overly optimistic?
-- 
Simon.
_______________________________________________
ceph-users mailing list
[email protected]
http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com

Reply via email to