Yes, according to crush algorithms, large drives are given high weight, this is expected. By default, crush gives no consideration of each drive's performance, which may cause the performance distribution is not balanced. And the highest io util osd may slow down the whole cluster. ________________________________________ From: Konstantin Shalygin <k0ste@xxxxxxxx> Sent: Thursday, April 12, 2018 11:29 To: ceph-users@xxxxxxxxxxxxxx Cc: ? ?? Subject: Re: osds with different disk sizes may killing performance > After digging into our internal system stats, we find the new added's disk io util is about two times than the old. This is obviously and expected. Yours 8Tb drives weighted double against 4Tb and do *double* crush work in comparison. k _______________________________________________ ceph-users mailing list ceph-users@xxxxxxxxxxxxxx http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
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