It seems like the cache tier should force promote when it gets an op the backing pool doesn't support. I think using the cache-pin mechanism would make sense. -Sam On Fri, Feb 5, 2016 at 7:53 AM, Jason Dillaman <dillaman@xxxxxxxxxx> wrote: > #1 and #2 are awkward for existing pools since we would need a tool to inject dummy omap values within existing images. Can the cache tier force-promote it from the EC pool to the cache when an unsupported op is encountered? There is logic like that in jewel/master for handling the proxied writes. > > -- > > Jason Dillaman > > ----- Original Message ----- >> From: "Sage Weil" <sweil@xxxxxxxxxx> >> To: "Nick Fisk" <nick@xxxxxxxxxx> >> Cc: "Jason Dillaman" <dillaman@xxxxxxxxxx>, ceph-users@xxxxxxxxxxxxxx, ceph-devel@xxxxxxxxxxxxxxx >> Sent: Friday, February 5, 2016 10:42:17 AM >> Subject: cls_rbd ops on rbd_id.$name objects in EC pool >> >> On Wed, 27 Jan 2016, Nick Fisk wrote: >> > >> > > -----Original Message----- >> > > From: ceph-users [mailto:ceph-users-bounces@xxxxxxxxxxxxxx] On Behalf Of >> > > Jason Dillaman >> > > Sent: 27 January 2016 14:25 >> > > To: Nick Fisk <nick@xxxxxxxxxx> >> > > Cc: ceph-users@xxxxxxxxxxxxxx >> > > Subject: Re: Possible Cache Tier Bug - Can someone confirm >> > > >> > > Are you running with an EC pool behind the cache tier? I know there was >> > > an >> > > issue with the first Infernalis release where unsupported ops were being >> > > proxied down to the EC pool, resulting in that same error. >> > >> > Hi Jason, yes I am. 3x Replicated pool on top of an EC pool. >> > >> > It's probably something similar to what you mention. Either the client >> > should be able to access the RBD header object on the base pool, or it >> > should be flagged so that it can't be evicted. >> >> I just confirmed that the rbd_id.$name object doesn't have any omap, so >> from rados's perspective, flushing and evicting it is fine. But yeah, the >> cls_rbd ops aren't permitted in the EC pool. >> >> In master/jewel we have a cache-pin function that prevents an object from >> being flushed. >> >> A few options are: >> >> 1) Have cls_rbd cache-pin it's objects. >> >> 2) Have cls_rbd put an omap key on the object to indirectly do the same. >> >> 3) Add a requires-cls type object flag that keeps hte object out of an EC >> pool *until* it eventually supports cls ops. >> >> I'd lean toward 1 since it's simple and explicit, and when we eventually >> make classes work we can remove the cache-pin behavior from cls_rbd. >> It's harder to fix in infernalis unless we also backport cache-pin/unpin >> ops, too, so maybe #2 would be a simple infernalis workaround? >> >> Jason? Sam? >> sage >> >> >> >> > >> > > >> > > -- >> > > >> > > Jason Dillaman >> > > >> > > >> > > ----- Original Message ----- >> > > > From: "Nick Fisk" <nick@xxxxxxxxxx> >> > > > To: ceph-users@xxxxxxxxxxxxxx >> > > > Sent: Wednesday, January 27, 2016 8:46:53 AM >> > > > Subject: Possible Cache Tier Bug - Can someone confirm >> > > > >> > > > Hi All, >> > > > >> > > > I think I have stumbled on a bug. I'm running Infernalis (Kernel 4.4 >> > > > on the >> > > > client) and it seems that if the RBD header object gets evicted from >> > > > the cache pool then you can no longer map it. >> > > > >> > > > Steps to reproduce >> > > > >> > > > rbd -p cache1 create Test --size=10G >> > > > rbd - p cache1 map Test >> > > > >> > > > /dev/rbd1 <-Works!! >> > > > >> > > > rbd unmap /dev/rbd1 >> > > > >> > > > rados -p cache1 cache-flush rbd_id.Test rados -p cache1 cache-evict >> > > > rbd_id.Test rbd - p cache1 map Test >> > > > >> > > > rbd: sysfs write failed >> > > > rbd: map failed: (95) Operation not supported >> > > > >> > > > or with the rbd-nbd client >> > > > >> > > > 2016-01-27 13:39:52.686770 7f9e54162b00 -1 asok(0x561837b88360) >> > > > AdminSocketConfigObs::init: failed: AdminSocket::bind_and_listen: >> > > > failed to bind the UNIX domain socket to >> > > > '/var/run/ceph/ceph-client.admin.asok': (17) File exists >> > > > 2016-01-27 13:39:52.703987 7f9e32ffd700 -1 librbd::image::OpenRequest: >> > > > failed to retrieve image id: (95) Operation not supported >> > > > rbd-nbd: failed to map, status: (95) Operation not supported >> > > > 2016-01-27 13:39:52.704138 7f9e327fc700 -1 librbd::ImageState: failed >> > > > to open image: (95) Operation not supported >> > > > >> > > > Nick >> > > > >> > > > _______________________________________________ >> > > > 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 >> > >> > _______________________________________________ >> > ceph-users mailing list >> > ceph-users@xxxxxxxxxxxxxx >> > http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com >> > >> > >> -- >> To unsubscribe from this list: send the line "unsubscribe ceph-devel" in >> the body of a message to majordomo@xxxxxxxxxxxxxxx >> More majordomo info at http://vger.kernel.org/majordomo-info.html >> > -- > To unsubscribe from this list: send the line "unsubscribe ceph-devel" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html _______________________________________________ ceph-users mailing list ceph-users@xxxxxxxxxxxxxx http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
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