Hi all, I use the kernel rbd with kernel 3.18 and open the discard option. When I use the cache tier mode, the performance is ruined by CEPH_OSD_OP_DELETE. Since some one may delete a large file which is rarely used, the file is always not in the Cache pool. So it will promote the object first from the cold pool and then replace the object with an empty object. After the empty object is flushed and evicted, the content is eventually deleted. But a large file causes lots of object promotion so that the Cache pool's bandwidth is saturated. We might not need to promote a delete the object when Calling can_skip_promote() and send a CEPH_OSD_OP_DELETE op to cold pool from the Objecter interface, which would be much better when deleting file occurs. Is that possible? Regards Ning Yao -- 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
