Hi ceph-devel, We enhanced the crushtool to simulate real pg distribution for a specific pool. Recently we had encountered pg uneven issue again after expanding our cluster, although we had re-weighted the cluster to make pg evenly-distribution at the time we built up the cluster. It could be painful to re-weighted osds after expanding cluster because in order to achieve pg evenly-distribution, we may need to re-weight couple of times and each time will trigger data movement. Now we could use this crushtool to simulate pg distribution against crush map, re-weight osds and test the crush map again and again until we satisfy with pg distribution. Then we could set back the final crush map and trigger data movement for one time. Please check this PR: https://github.com/ceph/ceph/pull/6004 if your guys are interested. Thanks. Zhi Zhang (David) -- 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
