Hi, I'm thinking about building a ceph cluster and I'm wondering what a good configuration would look like for 4-8 (and maybe more) 2HU 8-disk or 3HU 16-disk systems. Would it make sense to make each disk an individual OSD or should I perhaps create several raid-0 and create OSDs from those? Also what is the best setup for the journal? If I understand it correctly then each OSD needs its own journal and that should be a separate disk but that would be quite wasteful it seems. Would it make sense to put in two small SSD disks in a raid-1 configuration and create a filesystem for each OSD journal on it? How does the number of OSDs/Nodes affect the performance of say a single dd operation? Will blocks be distributed over the cluster and written/read in parallel or does the number only improve concurrency rather than benefit single threaded workloads? Regards, Dennis -- 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
