On Thu, Jun 26, 2014 at 7:03 AM, Micha Krause <mi...@krausam.de> wrote: > Hi, > > could someone explain to me what the difference is between > > ceph osd reweight > > and > > ceph osd crush reweight
"ceph osd crush reweight" sets the CRUSH weight of the OSD. This weight is an arbitrary value (generally the size of the disk in TB or something) and controls how much data the system tries to allocate to the OSD. "ceph osd reweight" sets an override weight on the OSD. This value is in the range 0 to 1, and forces CRUSH to re-place (1-weight) of the data that would otherwise live on this drive. It does *not* change the weights assigned to the buckets above the OSD, and is a corrective measure in case the normal CRUSH distribution isn't working out quite right. (For instance, if one of your OSDs is at 90% and the others are at 50%, you could reduce this weight to try and compensate for it.) It looks like our docs aren't very clear on the difference, when it even mentions them...and admittedly it's a pretty subtle issue! -Greg Software Engineer #42 @ http://inktank.com | http://ceph.com _______________________________________________ ceph-users mailing list ceph-users@lists.ceph.com http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
