On Tue, 19 Jun 2012, Stefan Priebe wrote: > Am 19.06.2012 um 17:42 schrieb Sage Weil <sage@xxxxxxxxxxx>: > >> > >> But this number 2176 of PGs were set while doing mkcephfs - how is it > >> calculated? > > > > num_pgs = num_osds << osd_pg_bits > > > > which is configurable via --osd-pg-bits N or ceph.conf (at mkcephfs time). > > The default is 6. > > What happens if I add more osds later? Currently, nothing. The existing PGs are spread out among a larger number of OSDs. This is partly why the default shoots a bit high. One of the upcoming items on the todo list is to finish PG splitting/merging, which will allow a pool to be resharded into more or less PGs so that the data distribution can be adjusted as the cluster grows or shrinks. sage -- 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
