Sounds good, thanks for the info and will wait and test with next releases. > On Jun 27, 2015, at 9:24 AM, Nick Fisk <nick@xxxxxxxxxx> wrote: > > Hi Reid, > > Yes they will, but if the object which the user is writing to (Disk Block if > using RBD, which then maps to an object) has never been written to before, > it won't have to promote the object from the base pool before being able to > write it. > > However as you write each object, once the cache pool is full, another > object will be demoted down to the base tier. > > As long as you don't mind slow performance, using the cache tier should be > ok. Otherwise wait until the next release as there will be several > improvements. > >> -----Original Message----- >> From: ceph-users [mailto:ceph-users-bounces@xxxxxxxxxxxxxx] On Behalf Of >> Reid Kelley >> Sent: 27 June 2015 00:04 >> To: ceph-users@xxxxxxxxxxxxxx >> Subject: Trying to understand Cache Pool behavior >> >> Have been reading the docs and trying to wrap my head around the idea of a >> "write miss" with a cache tier in write-back mode. >> >> My use case is a large media archive, with write activity on file ingest >> (previews and thumbs generated) followed by very cold limited ready >> access. Seems to fit the cache model. >> >> What I am confused with is the write-miss. Would a user uploading a new > file >> every experience a write-miss? >> >> Thanks, >> Reid >> >> >> _______________________________________________ >> 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
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