Den tis 22 juni 2021 kl 11:55 skrev Thomas Roth <t.roth@xxxxxx>: > Hi all, > newbie question: > The documentation seems to suggest that with ceph-volume, one OSD is created for each HDD (cf. 4-HDD-example in > https://docs.ceph.com/en/latest/rados/configuration/bluestore-config-ref/) > > This seems odd: what if a server has a finite number of disks? I was going to try cephfs on ~10 servers with 70 HDD each. That would make each system > having to deal with 70 OSDs, on 70 LVs? > Really no aggregation of the disks? There is nothing inherently wrong with having 70 OSDs if you have 70 drives. As others have said, it brings benefits to allow single faults to be kept do as small a domain as possible and if you read up on ZFS guides, I am sure they will say the same thing, hand over each separate raw device over to zfs, and let zfs place the data in the optimal way for each raw device, instead of globbing together the lot and pretend it is one large disks when it actually isn't. With one huge 70-piece raid0 you might end up having a lot of writes and reads hit a small number of disks at a time which probably will be worse for your overall performance. -- May the most significant bit of your life be positive. _______________________________________________ ceph-users mailing list -- ceph-users@xxxxxxx To unsubscribe send an email to ceph-users-leave@xxxxxxx
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