Dear all, I need to expand a ceph cluster with minimal impact. Reading previous threads on this topic from the list I've found the ceph-gentle-reweight script (https://github.com/cernceph/ceph-scripts/blob/master/tools/ceph-gentle-reweight) created by Dan van der Ster (Thank you Dan for sharing the script with us!). I've done some experiments, and it looks promising, but it is needed to properly set the parameters. Did any of you tested this script before? what is the recommended delta_weight to be used? From the default parameters of the script I can see that the default delta weight is .5% of the target weight that means 200 reweighting cycles. I have experimented with a reweight ratio of 5% while running a fio test on a client. The results were OK (I mean no slow requests), but my test cluster was a very small one. If any of you has done some larger experiments with this script I would be really interested to read about your results. Thank you! Laszlo _______________________________________________ ceph-users mailing list ceph-users@xxxxxxxxxxxxxx http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
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