On 6/12/21 4:39 PM, Nathan Fish wrote: > I doubt it. The problem is that the CephFS MDS must perform > distributed metadata transactions with ordering and locking. > Whereas a filesystem on rbd runs locally and doesn't have to worry > about other computers writing to the same block device. > Our bottleneck in production is usually the MDS CPU load. Perhaps if an 'exclusive write mount' option existed, the mds could delegate most of what it does to the client. Moving 4K-at-least blocks around a network, even with 'jumbo frames' on local segments, has got to take more processing and network bandwidth than the 'known interesting only' parts of files. > > On Fri, Jun 11, 2021 at 12:31 PM Harry G. Coin <hgcoin@xxxxxxxxx> wrote: >> On any given a properly sized ceph setup, for other than database end >> use) theoretically shouldn't a ceph-fs root out-perform any fs atop a >> rados block device root? >> >> Seems to me like it ought to: moving only the 'interesting' bits of >> files over the so-called 'public' network should take fewer, smaller >> packets than the overhead associated with whole blocks that hold some >> fraction of the 'interesting' bits? >> >> Does it work that way in practice? >> >> >> >> >> _______________________________________________ >> ceph-users mailing list -- ceph-users@xxxxxxx >> To unsubscribe send an email to ceph-users-leave@xxxxxxx > _______________________________________________ > ceph-users mailing list -- ceph-users@xxxxxxx > To unsubscribe send an email to ceph-users-leave@xxxxxxx _______________________________________________ ceph-users mailing list -- ceph-users@xxxxxxx To unsubscribe send an email to ceph-users-leave@xxxxxxx
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