In the performance webinar last week (it is online for viewing), they mentioned that they are looking a ways to prevent single reads from entering cache or other optimizations. From what I understand it is still a very new feature so I'm sure it will see some good improvements. On Fri, Aug 22, 2014 at 3:13 PM, Andrei Mikhailovsky <andrei at arhont.com> wrote: > So it looks like using rbd export / import will negatively effect the > client performance, which is unfortunate. Is this really the case? Any > plans on changing this behavior in future versions of ceph? > > Cheers > > Andrei > > > ----- Original Message ----- > From: "Robert LeBlanc" <robert at leblancnet.us> > To: "Andrei Mikhailovsky" <andrei at arhont.com> > Cc: ceph-users at lists.ceph.com > Sent: Friday, 22 August, 2014 8:21:08 PM > Subject: Re: [ceph-users] pool with cache pool and rbd export > > > My understanding is that all reads are copied to the cache pool. This > would indicate that cache will be evicted. I don't know to what extent this > will affect the hot cache because we have not used a cache pool yet. I'm > currently looking into bcache fronting the disks to provide caching there. > > > Robert LeBlanc > > > > On Fri, Aug 22, 2014 at 12:41 PM, Andrei Mikhailovsky < andrei at arhont.com > > wrote: > > > Hello guys, > > I am planning to perform regular rbd pool off-site backup with rbd export > and export-diff. I've got a small ceph firefly cluster with an active > writeback cache pool made of couple of osds. I've got the following > question which I hope the ceph community could answer: > > Will this rbd export or import operations affect the active hot data in > the cache pool, thus evicting from the cache pool the real hot data used by > the clients. Or does the process of rbd export/import effect only the osds > and does not touch the cache pool? > > Many thanks > > Andrei > > _______________________________________________ > ceph-users mailing list > ceph-users at lists.ceph.com > http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com > > -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.ceph.com/pipermail/ceph-users-ceph.com/attachments/20140822/7ebc99e6/attachment.htm>
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