I am rather sleep deprived, so I may have misread things, but this doesn't seem to me to be the best benchmark to evaluate Ceph for database work.
From what I understand best practice in ceph for databases is to make a rbd image and format that with your filesystem of choice. I believe. The rbd stripe size should be tuned to you database writes in mind.
I believe ceph rbd supports rdma, but I cannot find much current details about it.
How not? You can map an rbd image from multiple VMs/servers at the same time, just if you want to do so you need a multi-client aware filesystem. Otherwise if you just need something attached to a single host you just format the volume ext4/xfs/whatever and map it, throw your database on that.
From what I understand best practice in ceph for databases is to make a rbd image and format that with your filesystem of choice. I believe. The rbd stripe size should be tuned to you database writes in mind.
I believe ceph rbd supports rdma, but I cannot find much current details about it.