> > I ran HTTach on one of my VM's and got a graph that looks like this: > > ___-____----- > > The low points are all ~35Mbytes/sec and the high points are all > ~60Mbytes/sec. This is very reproducible. > > HDTach does sample reads across the whole disk, so would I be right in > thinking that the variation is due to pg's being on different OSD's, and there is > a difference in performance because of a difference in my OSD's. > > Is there a way for me to identify which OSD's are letting me down here? > Presently I have 3: > > #1 - xfs with isize=256 > #2 - xfs with isize=2048 > #3 - btrfs > > I have my suspicions about which is dragging the chain, but how could I > confirm it? > It occurred to me that just stopping the OSD's selectively would allow me to see if there was a change when one was ejected, but at no time was there a change to the graph... James _______________________________________________ ceph-users mailing list ceph-users@xxxxxxxxxxxxxx http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
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