[ceph-users] any experience on using Bcache on top of HDD OSD

Dear Cephers, Just curious about any one who has some experience on using Bcache on top of HDD OSD to accelerate IOPS performance? If any, how about the stability and the performance improvement, and for how long the running time? I am evaluating whether its is worth to use Bcache on top of HDD OSD. I have done some experimental on using bcache with OSD, and would like to make sure before doing it on a production cluster. thanks in advance, samuel huxiaoyu@horebdata.cn