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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